The GPT-3 Algorithm Wrote Articles For Two Weeks — And 26,000 People Read It

The GPT-3 algorithm wrote articles for two weeks — they were read by 26 thousand people and only one asked the author if it was a robot. Some users suspected that the texts were written by an algorithm — but they were minus and accused of incorrectness.

UC Berkeley student Liam Porr used the GPT-3 algorithm to write blog articles on the web-based aggregator Hacker News.

Porr did the title and intro, add a photo, and GPT-3 did the rest. For two weeks the blog was visited by over 26 thousand users, 60 people subscribed to the author, the student said.

#computer-science #data-science #ai #writing #machine-learning

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The GPT-3 Algorithm Wrote Articles For Two Weeks — And 26,000 People Read It

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A Pure PHP Implementation Of The MessagePack Serialization Format

msgpack.php

A pure PHP implementation of the MessagePack serialization format.

Features

Fully compliant with the latest MessagePack specification
Supports streaming unpacking
Supports unsigned 64-bit integers handling
Supports object serialization
Fully tested
Relatively fast

Installation

The recommended way to install the library is through Composer:

composer require rybakit/msgpack

Usage

Packing

To pack values you can either use an instance of a Packer:

$packer = new Packer();
$packed = $packer->pack($value);

or call a static method on the MessagePack class:

$packed = MessagePack::pack($value);

In the examples above, the method pack automatically packs a value depending on its type. However, not all PHP types can be uniquely translated to MessagePack types. For example, the MessagePack format defines map and array types, which are represented by a single array type in PHP. By default, the packer will pack a PHP array as a MessagePack array if it has sequential numeric keys, starting from 0 and as a MessagePack map otherwise:

$mpArr1 = $packer->pack([1, 2]);               // MP array [1, 2]
$mpArr2 = $packer->pack([0 => 1, 1 => 2]);     // MP array [1, 2]
$mpMap1 = $packer->pack([0 => 1, 2 => 3]);     // MP map {0: 1, 2: 3}
$mpMap2 = $packer->pack([1 => 2, 2 => 3]);     // MP map {1: 2, 2: 3}
$mpMap3 = $packer->pack(['a' => 1, 'b' => 2]); // MP map {a: 1, b: 2}

However, sometimes you need to pack a sequential array as a MessagePack map. To do this, use the packMap method:

$mpMap = $packer->packMap([1, 2]); // {0: 1, 1: 2}

Here is a list of type-specific packing methods:

$packer->packNil();           // MP nil
$packer->packBool(true);      // MP bool
$packer->packInt(42);         // MP int
$packer->packFloat(M_PI);     // MP float (32 or 64)
$packer->packFloat32(M_PI);   // MP float 32
$packer->packFloat64(M_PI);   // MP float 64
$packer->packStr('foo');      // MP str
$packer->packBin("\x80");     // MP bin
$packer->packArray([1, 2]);   // MP array
$packer->packMap(['a' => 1]); // MP map
$packer->packExt(1, "\xaa");  // MP ext

Check the "Custom types" section below on how to pack custom types.

Packing options

The Packer object supports a number of bitmask-based options for fine-tuning the packing process (defaults are in bold):

Name	Description
`FORCE_STR`	Forces PHP strings to be packed as MessagePack UTF-8 strings
`FORCE_BIN`	Forces PHP strings to be packed as MessagePack binary data
`DETECT_STR_BIN`	Detects MessagePack str/bin type automatically

`FORCE_ARR`	Forces PHP arrays to be packed as MessagePack arrays
`FORCE_MAP`	Forces PHP arrays to be packed as MessagePack maps
`DETECT_ARR_MAP`	Detects MessagePack array/map type automatically

`FORCE_FLOAT32`	Forces PHP floats to be packed as 32-bits MessagePack floats
`FORCE_FLOAT64`	Forces PHP floats to be packed as 64-bits MessagePack floats

The type detection mode (DETECT_STR_BIN/DETECT_ARR_MAP) adds some overhead which can be noticed when you pack large (16- and 32-bit) arrays or strings. However, if you know the value type in advance (for example, you only work with UTF-8 strings or/and associative arrays), you can eliminate this overhead by forcing the packer to use the appropriate type, which will save it from running the auto-detection routine. Another option is to explicitly specify the value type. The library provides 2 auxiliary classes for this, Map and Bin. Check the "Custom types" section below for details.

Examples:

// detect str/bin type and pack PHP 64-bit floats (doubles) to MP 32-bit floats
$packer = new Packer(PackOptions::DETECT_STR_BIN | PackOptions::FORCE_FLOAT32);

// these will throw MessagePack\Exception\InvalidOptionException
$packer = new Packer(PackOptions::FORCE_STR | PackOptions::FORCE_BIN);
$packer = new Packer(PackOptions::FORCE_FLOAT32 | PackOptions::FORCE_FLOAT64);

Unpacking

To unpack data you can either use an instance of a BufferUnpacker:

$unpacker = new BufferUnpacker();

$unpacker->reset($packed);
$value = $unpacker->unpack();

or call a static method on the MessagePack class:

$value = MessagePack::unpack($packed);

If the packed data is received in chunks (e.g. when reading from a stream), use the tryUnpack method, which attempts to unpack data and returns an array of unpacked messages (if any) instead of throwing an InsufficientDataException:

while ($chunk = ...) {
    $unpacker->append($chunk);
    if ($messages = $unpacker->tryUnpack()) {
        return $messages;
    }
}

If you want to unpack from a specific position in a buffer, use seek:

$unpacker->seek(42); // set position equal to 42 bytes
$unpacker->seek(-8); // set position to 8 bytes before the end of the buffer

To skip bytes from the current position, use skip:

$unpacker->skip(10); // set position to 10 bytes ahead of the current position

To get the number of remaining (unread) bytes in the buffer:

$unreadBytesCount = $unpacker->getRemainingCount();

To check whether the buffer has unread data:

$hasUnreadBytes = $unpacker->hasRemaining();

If needed, you can remove already read data from the buffer by calling:

$releasedBytesCount = $unpacker->release();

With the read method you can read raw (packed) data:

$packedData = $unpacker->read(2); // read 2 bytes

Besides the above methods BufferUnpacker provides type-specific unpacking methods, namely:

$unpacker->unpackNil();   // PHP null
$unpacker->unpackBool();  // PHP bool
$unpacker->unpackInt();   // PHP int
$unpacker->unpackFloat(); // PHP float
$unpacker->unpackStr();   // PHP UTF-8 string
$unpacker->unpackBin();   // PHP binary string
$unpacker->unpackArray(); // PHP sequential array
$unpacker->unpackMap();   // PHP associative array
$unpacker->unpackExt();   // PHP MessagePack\Type\Ext object

Unpacking options

The BufferUnpacker object supports a number of bitmask-based options for fine-tuning the unpacking process (defaults are in bold):

Name	Description
`BIGINT_AS_STR`	Converts overflowed integers to strings [1]
`BIGINT_AS_GMP`	Converts overflowed integers to `GMP` objects [2]
`BIGINT_AS_DEC`	Converts overflowed integers to `Decimal\Decimal` objects [3]

1. The binary MessagePack format has unsigned 64-bit as its largest integer data type, but PHP does not support such integers, which means that an overflow can occur during unpacking.
2. Make sure the GMP extension is enabled.
3. Make sure the Decimal extension is enabled.

Examples:

$packedUint64 = "\xcf"."\xff\xff\xff\xff"."\xff\xff\xff\xff";

$unpacker = new BufferUnpacker($packedUint64);
var_dump($unpacker->unpack()); // string(20) "18446744073709551615"

$unpacker = new BufferUnpacker($packedUint64, UnpackOptions::BIGINT_AS_GMP);
var_dump($unpacker->unpack()); // object(GMP) {...}

$unpacker = new BufferUnpacker($packedUint64, UnpackOptions::BIGINT_AS_DEC);
var_dump($unpacker->unpack()); // object(Decimal\Decimal) {...}

Custom types

In addition to the basic types, the library provides functionality to serialize and deserialize arbitrary types. This can be done in several ways, depending on your use case. Let's take a look at them.

Type objects

If you need to serialize an instance of one of your classes into one of the basic MessagePack types, the best way to do this is to implement the CanBePacked interface in the class. A good example of such a class is the Map type class that comes with the library. This type is useful when you want to explicitly specify that a given PHP array should be packed as a MessagePack map without triggering an automatic type detection routine:

$packer = new Packer();

$packedMap = $packer->pack(new Map([1, 2, 3]));
$packedArray = $packer->pack([1, 2, 3]);

More type examples can be found in the src/Type directory.

Type transformers

As with type objects, type transformers are only responsible for serializing values. They should be used when you need to serialize a value that does not implement the CanBePacked interface. Examples of such values could be instances of built-in or third-party classes that you don't own, or non-objects such as resources.

A transformer class must implement the CanPack interface. To use a transformer, it must first be registered in the packer. Here is an example of how to serialize PHP streams into the MessagePack bin format type using one of the supplied transformers, StreamTransformer:

$packer = new Packer(null, [new StreamTransformer()]);

$packedBin = $packer->pack(fopen('/path/to/file', 'r+'));

More type transformer examples can be found in the src/TypeTransformer directory.

Extensions

In contrast to the cases described above, extensions are intended to handle extension types and are responsible for both serialization and deserialization of values (types).

An extension class must implement the Extension interface. To use an extension, it must first be registered in the packer and the unpacker.

The MessagePack specification divides extension types into two groups: predefined and application-specific. Currently, there is only one predefined type in the specification, Timestamp.

Timestamp

The Timestamp extension type is a predefined type. Support for this type in the library is done through the TimestampExtension class. This class is responsible for handling Timestamp objects, which represent the number of seconds and optional adjustment in nanoseconds:

$timestampExtension = new TimestampExtension();

$packer = new Packer();
$packer = $packer->extendWith($timestampExtension);

$unpacker = new BufferUnpacker();
$unpacker = $unpacker->extendWith($timestampExtension);

$packedTimestamp = $packer->pack(Timestamp::now());
$timestamp = $unpacker->reset($packedTimestamp)->unpack();

$seconds = $timestamp->getSeconds();
$nanoseconds = $timestamp->getNanoseconds();

When using the MessagePack class, the Timestamp extension is already registered:

$packedTimestamp = MessagePack::pack(Timestamp::now());
$timestamp = MessagePack::unpack($packedTimestamp);

Application-specific extensions

In addition, the format can be extended with your own types. For example, to make the built-in PHP DateTime objects first-class citizens in your code, you can create a corresponding extension, as shown in the example. Please note, that custom extensions have to be registered with a unique extension ID (an integer from 0 to 127).

More extension examples can be found in the examples/MessagePack directory.

To learn more about how extension types can be useful, check out this article.

Exceptions

If an error occurs during packing/unpacking, a PackingFailedException or an UnpackingFailedException will be thrown, respectively. In addition, an InsufficientDataException can be thrown during unpacking.

An InvalidOptionException will be thrown in case an invalid option (or a combination of mutually exclusive options) is used.

Tests

Run tests as follows:

vendor/bin/phpunit

Also, if you already have Docker installed, you can run the tests in a docker container. First, create a container:

./dockerfile.sh | docker build -t msgpack -

The command above will create a container named msgpack with PHP 8.1 runtime. You may change the default runtime by defining the PHP_IMAGE environment variable:

PHP_IMAGE='php:8.0-cli' ./dockerfile.sh | docker build -t msgpack -

See a list of various images here.

Then run the unit tests:

docker run --rm -v $PWD:/msgpack -w /msgpack msgpack

Fuzzing

To ensure that the unpacking works correctly with malformed/semi-malformed data, you can use a testing technique called Fuzzing. The library ships with a help file (target) for PHP-Fuzzer and can be used as follows:

php-fuzzer fuzz tests/fuzz_buffer_unpacker.php

Performance

To check performance, run:

php -n -dzend_extension=opcache.so \
-dpcre.jit=1 -dopcache.enable=1 -dopcache.enable_cli=1 \
tests/bench.php

Example output

Filter: MessagePack\Tests\Perf\Filter\ListFilter
Rounds: 3
Iterations: 100000

=============================================
Test/Target            Packer  BufferUnpacker
---------------------------------------------
nil .................. 0.0030 ........ 0.0139
false ................ 0.0037 ........ 0.0144
true ................. 0.0040 ........ 0.0137
7-bit uint #1 ........ 0.0052 ........ 0.0120
7-bit uint #2 ........ 0.0059 ........ 0.0114
7-bit uint #3 ........ 0.0061 ........ 0.0119
5-bit sint #1 ........ 0.0067 ........ 0.0126
5-bit sint #2 ........ 0.0064 ........ 0.0132
5-bit sint #3 ........ 0.0066 ........ 0.0135
8-bit uint #1 ........ 0.0078 ........ 0.0200
8-bit uint #2 ........ 0.0077 ........ 0.0212
8-bit uint #3 ........ 0.0086 ........ 0.0203
16-bit uint #1 ....... 0.0111 ........ 0.0271
16-bit uint #2 ....... 0.0115 ........ 0.0260
16-bit uint #3 ....... 0.0103 ........ 0.0273
32-bit uint #1 ....... 0.0116 ........ 0.0326
32-bit uint #2 ....... 0.0118 ........ 0.0332
32-bit uint #3 ....... 0.0127 ........ 0.0325
64-bit uint #1 ....... 0.0140 ........ 0.0277
64-bit uint #2 ....... 0.0134 ........ 0.0294
64-bit uint #3 ....... 0.0134 ........ 0.0281
8-bit int #1 ......... 0.0086 ........ 0.0241
8-bit int #2 ......... 0.0089 ........ 0.0225
8-bit int #3 ......... 0.0085 ........ 0.0229
16-bit int #1 ........ 0.0118 ........ 0.0280
16-bit int #2 ........ 0.0121 ........ 0.0270
16-bit int #3 ........ 0.0109 ........ 0.0274
32-bit int #1 ........ 0.0128 ........ 0.0346
32-bit int #2 ........ 0.0118 ........ 0.0339
32-bit int #3 ........ 0.0135 ........ 0.0368
64-bit int #1 ........ 0.0138 ........ 0.0276
64-bit int #2 ........ 0.0132 ........ 0.0286
64-bit int #3 ........ 0.0137 ........ 0.0274
64-bit int #4 ........ 0.0180 ........ 0.0285
64-bit float #1 ...... 0.0134 ........ 0.0284
64-bit float #2 ...... 0.0125 ........ 0.0275
64-bit float #3 ...... 0.0126 ........ 0.0283
fix string #1 ........ 0.0035 ........ 0.0133
fix string #2 ........ 0.0094 ........ 0.0216
fix string #3 ........ 0.0094 ........ 0.0222
fix string #4 ........ 0.0091 ........ 0.0241
8-bit string #1 ...... 0.0122 ........ 0.0301
8-bit string #2 ...... 0.0118 ........ 0.0304
8-bit string #3 ...... 0.0119 ........ 0.0315
16-bit string #1 ..... 0.0150 ........ 0.0388
16-bit string #2 ..... 0.1545 ........ 0.1665
32-bit string ........ 0.1570 ........ 0.1756
wide char string #1 .. 0.0091 ........ 0.0236
wide char string #2 .. 0.0122 ........ 0.0313
8-bit binary #1 ...... 0.0100 ........ 0.0302
8-bit binary #2 ...... 0.0123 ........ 0.0324
8-bit binary #3 ...... 0.0126 ........ 0.0327
16-bit binary ........ 0.0168 ........ 0.0372
32-bit binary ........ 0.1588 ........ 0.1754
fix array #1 ......... 0.0042 ........ 0.0131
fix array #2 ......... 0.0294 ........ 0.0367
fix array #3 ......... 0.0412 ........ 0.0472
16-bit array #1 ...... 0.1378 ........ 0.1596
16-bit array #2 ........... S ............. S
32-bit array .............. S ............. S
complex array ........ 0.1865 ........ 0.2283
fix map #1 ........... 0.0725 ........ 0.1048
fix map #2 ........... 0.0319 ........ 0.0405
fix map #3 ........... 0.0356 ........ 0.0665
fix map #4 ........... 0.0465 ........ 0.0497
16-bit map #1 ........ 0.2540 ........ 0.3028
16-bit map #2 ............. S ............. S
32-bit map ................ S ............. S
complex map .......... 0.2372 ........ 0.2710
fixext 1 ............. 0.0283 ........ 0.0358
fixext 2 ............. 0.0291 ........ 0.0371
fixext 4 ............. 0.0302 ........ 0.0355
fixext 8 ............. 0.0288 ........ 0.0384
fixext 16 ............ 0.0293 ........ 0.0359
8-bit ext ............ 0.0302 ........ 0.0439
16-bit ext ........... 0.0334 ........ 0.0499
32-bit ext ........... 0.1845 ........ 0.1888
32-bit timestamp #1 .. 0.0337 ........ 0.0547
32-bit timestamp #2 .. 0.0335 ........ 0.0560
64-bit timestamp #1 .. 0.0371 ........ 0.0575
64-bit timestamp #2 .. 0.0374 ........ 0.0542
64-bit timestamp #3 .. 0.0356 ........ 0.0533
96-bit timestamp #1 .. 0.0362 ........ 0.0699
96-bit timestamp #2 .. 0.0381 ........ 0.0701
96-bit timestamp #3 .. 0.0367 ........ 0.0687
=============================================
Total                  2.7618          4.0820
Skipped                     4               4
Failed                      0               0
Ignored                     0               0

With JIT:

php -n -dzend_extension=opcache.so \
-dpcre.jit=1 -dopcache.jit_buffer_size=64M -dopcache.jit=tracing -dopcache.enable=1 -dopcache.enable_cli=1 \
tests/bench.php

Example output

Filter: MessagePack\Tests\Perf\Filter\ListFilter
Rounds: 3
Iterations: 100000

=============================================
Test/Target            Packer  BufferUnpacker
---------------------------------------------
nil .................. 0.0005 ........ 0.0054
false ................ 0.0004 ........ 0.0059
true ................. 0.0004 ........ 0.0059
7-bit uint #1 ........ 0.0010 ........ 0.0047
7-bit uint #2 ........ 0.0010 ........ 0.0046
7-bit uint #3 ........ 0.0010 ........ 0.0046
5-bit sint #1 ........ 0.0025 ........ 0.0046
5-bit sint #2 ........ 0.0023 ........ 0.0046
5-bit sint #3 ........ 0.0024 ........ 0.0045
8-bit uint #1 ........ 0.0043 ........ 0.0081
8-bit uint #2 ........ 0.0043 ........ 0.0079
8-bit uint #3 ........ 0.0041 ........ 0.0080
16-bit uint #1 ....... 0.0064 ........ 0.0095
16-bit uint #2 ....... 0.0064 ........ 0.0091
16-bit uint #3 ....... 0.0064 ........ 0.0094
32-bit uint #1 ....... 0.0085 ........ 0.0114
32-bit uint #2 ....... 0.0077 ........ 0.0122
32-bit uint #3 ....... 0.0077 ........ 0.0120
64-bit uint #1 ....... 0.0085 ........ 0.0159
64-bit uint #2 ....... 0.0086 ........ 0.0157
64-bit uint #3 ....... 0.0086 ........ 0.0158
8-bit int #1 ......... 0.0042 ........ 0.0080
8-bit int #2 ......... 0.0042 ........ 0.0080
8-bit int #3 ......... 0.0042 ........ 0.0081
16-bit int #1 ........ 0.0065 ........ 0.0095
16-bit int #2 ........ 0.0065 ........ 0.0090
16-bit int #3 ........ 0.0056 ........ 0.0085
32-bit int #1 ........ 0.0067 ........ 0.0107
32-bit int #2 ........ 0.0066 ........ 0.0106
32-bit int #3 ........ 0.0063 ........ 0.0104
64-bit int #1 ........ 0.0072 ........ 0.0162
64-bit int #2 ........ 0.0073 ........ 0.0174
64-bit int #3 ........ 0.0072 ........ 0.0164
64-bit int #4 ........ 0.0077 ........ 0.0161
64-bit float #1 ...... 0.0053 ........ 0.0135
64-bit float #2 ...... 0.0053 ........ 0.0135
64-bit float #3 ...... 0.0052 ........ 0.0135
fix string #1 ....... -0.0002 ........ 0.0044
fix string #2 ........ 0.0035 ........ 0.0067
fix string #3 ........ 0.0035 ........ 0.0077
fix string #4 ........ 0.0033 ........ 0.0078
8-bit string #1 ...... 0.0059 ........ 0.0110
8-bit string #2 ...... 0.0063 ........ 0.0121
8-bit string #3 ...... 0.0064 ........ 0.0124
16-bit string #1 ..... 0.0099 ........ 0.0146
16-bit string #2 ..... 0.1522 ........ 0.1474
32-bit string ........ 0.1511 ........ 0.1483
wide char string #1 .. 0.0039 ........ 0.0084
wide char string #2 .. 0.0073 ........ 0.0123
8-bit binary #1 ...... 0.0040 ........ 0.0112
8-bit binary #2 ...... 0.0075 ........ 0.0123
8-bit binary #3 ...... 0.0077 ........ 0.0129
16-bit binary ........ 0.0096 ........ 0.0145
32-bit binary ........ 0.1535 ........ 0.1479
fix array #1 ......... 0.0008 ........ 0.0061
fix array #2 ......... 0.0121 ........ 0.0165
fix array #3 ......... 0.0193 ........ 0.0222
16-bit array #1 ...... 0.0607 ........ 0.0479
16-bit array #2 ........... S ............. S
32-bit array .............. S ............. S
complex array ........ 0.0749 ........ 0.0824
fix map #1 ........... 0.0329 ........ 0.0431
fix map #2 ........... 0.0161 ........ 0.0189
fix map #3 ........... 0.0205 ........ 0.0262
fix map #4 ........... 0.0252 ........ 0.0205
16-bit map #1 ........ 0.1016 ........ 0.0927
16-bit map #2 ............. S ............. S
32-bit map ................ S ............. S
complex map .......... 0.1096 ........ 0.1030
fixext 1 ............. 0.0157 ........ 0.0161
fixext 2 ............. 0.0175 ........ 0.0183
fixext 4 ............. 0.0156 ........ 0.0185
fixext 8 ............. 0.0163 ........ 0.0184
fixext 16 ............ 0.0164 ........ 0.0182
8-bit ext ............ 0.0158 ........ 0.0207
16-bit ext ........... 0.0203 ........ 0.0219
32-bit ext ........... 0.1614 ........ 0.1539
32-bit timestamp #1 .. 0.0195 ........ 0.0249
32-bit timestamp #2 .. 0.0188 ........ 0.0260
64-bit timestamp #1 .. 0.0207 ........ 0.0281
64-bit timestamp #2 .. 0.0212 ........ 0.0291
64-bit timestamp #3 .. 0.0207 ........ 0.0295
96-bit timestamp #1 .. 0.0222 ........ 0.0358
96-bit timestamp #2 .. 0.0228 ........ 0.0353
96-bit timestamp #3 .. 0.0210 ........ 0.0319
=============================================
Total                  1.6432          1.9674
Skipped                     4               4
Failed                      0               0
Ignored                     0               0

You may change default benchmark settings by defining the following environment variables:

Name	Default
MP_BENCH_TARGETS	`pure_p,pure_u`, see a list of available targets
MP_BENCH_ITERATIONS	`100_000`
MP_BENCH_DURATION	not set
MP_BENCH_ROUNDS	`3`
MP_BENCH_TESTS	`-@slow`, see a list of available tests

For example:

export MP_BENCH_TARGETS=pure_p
export MP_BENCH_ITERATIONS=1000000
export MP_BENCH_ROUNDS=5
# a comma separated list of test names
export MP_BENCH_TESTS='complex array, complex map'
# or a group name
# export MP_BENCH_TESTS='-@slow' // @pecl_comp
# or a regexp
# export MP_BENCH_TESTS='/complex (array|map)/'

Another example, benchmarking both the library and the PECL extension:

MP_BENCH_TARGETS=pure_p,pure_u,pecl_p,pecl_u \
php -n -dextension=msgpack.so -dzend_extension=opcache.so \
-dpcre.jit=1 -dopcache.enable=1 -dopcache.enable_cli=1 \
tests/bench.php

Example output

Filter: MessagePack\Tests\Perf\Filter\ListFilter
Rounds: 3
Iterations: 100000

===========================================================================
Test/Target            Packer  BufferUnpacker  msgpack_pack  msgpack_unpack
---------------------------------------------------------------------------
nil .................. 0.0031 ........ 0.0141 ...... 0.0055 ........ 0.0064
false ................ 0.0039 ........ 0.0154 ...... 0.0056 ........ 0.0053
true ................. 0.0038 ........ 0.0139 ...... 0.0056 ........ 0.0044
7-bit uint #1 ........ 0.0061 ........ 0.0110 ...... 0.0059 ........ 0.0046
7-bit uint #2 ........ 0.0065 ........ 0.0119 ...... 0.0042 ........ 0.0029
7-bit uint #3 ........ 0.0054 ........ 0.0117 ...... 0.0045 ........ 0.0025
5-bit sint #1 ........ 0.0047 ........ 0.0103 ...... 0.0038 ........ 0.0022
5-bit sint #2 ........ 0.0048 ........ 0.0117 ...... 0.0038 ........ 0.0022
5-bit sint #3 ........ 0.0046 ........ 0.0102 ...... 0.0038 ........ 0.0023
8-bit uint #1 ........ 0.0063 ........ 0.0174 ...... 0.0039 ........ 0.0031
8-bit uint #2 ........ 0.0063 ........ 0.0167 ...... 0.0040 ........ 0.0029
8-bit uint #3 ........ 0.0063 ........ 0.0168 ...... 0.0039 ........ 0.0030
16-bit uint #1 ....... 0.0092 ........ 0.0222 ...... 0.0049 ........ 0.0030
16-bit uint #2 ....... 0.0096 ........ 0.0227 ...... 0.0042 ........ 0.0046
16-bit uint #3 ....... 0.0123 ........ 0.0274 ...... 0.0059 ........ 0.0051
32-bit uint #1 ....... 0.0136 ........ 0.0331 ...... 0.0060 ........ 0.0048
32-bit uint #2 ....... 0.0130 ........ 0.0336 ...... 0.0070 ........ 0.0048
32-bit uint #3 ....... 0.0127 ........ 0.0329 ...... 0.0051 ........ 0.0048
64-bit uint #1 ....... 0.0126 ........ 0.0268 ...... 0.0055 ........ 0.0049
64-bit uint #2 ....... 0.0135 ........ 0.0281 ...... 0.0052 ........ 0.0046
64-bit uint #3 ....... 0.0131 ........ 0.0274 ...... 0.0069 ........ 0.0044
8-bit int #1 ......... 0.0077 ........ 0.0236 ...... 0.0058 ........ 0.0044
8-bit int #2 ......... 0.0087 ........ 0.0244 ...... 0.0058 ........ 0.0048
8-bit int #3 ......... 0.0084 ........ 0.0241 ...... 0.0055 ........ 0.0049
16-bit int #1 ........ 0.0112 ........ 0.0271 ...... 0.0048 ........ 0.0045
16-bit int #2 ........ 0.0124 ........ 0.0292 ...... 0.0057 ........ 0.0049
16-bit int #3 ........ 0.0118 ........ 0.0270 ...... 0.0058 ........ 0.0050
32-bit int #1 ........ 0.0137 ........ 0.0366 ...... 0.0058 ........ 0.0051
32-bit int #2 ........ 0.0133 ........ 0.0366 ...... 0.0056 ........ 0.0049
32-bit int #3 ........ 0.0129 ........ 0.0350 ...... 0.0052 ........ 0.0048
64-bit int #1 ........ 0.0145 ........ 0.0254 ...... 0.0034 ........ 0.0025
64-bit int #2 ........ 0.0097 ........ 0.0214 ...... 0.0034 ........ 0.0025
64-bit int #3 ........ 0.0096 ........ 0.0287 ...... 0.0059 ........ 0.0050
64-bit int #4 ........ 0.0143 ........ 0.0277 ...... 0.0059 ........ 0.0046
64-bit float #1 ...... 0.0134 ........ 0.0281 ...... 0.0057 ........ 0.0052
64-bit float #2 ...... 0.0141 ........ 0.0281 ...... 0.0057 ........ 0.0050
64-bit float #3 ...... 0.0144 ........ 0.0282 ...... 0.0057 ........ 0.0050
fix string #1 ........ 0.0036 ........ 0.0143 ...... 0.0066 ........ 0.0053
fix string #2 ........ 0.0107 ........ 0.0222 ...... 0.0065 ........ 0.0068
fix string #3 ........ 0.0116 ........ 0.0245 ...... 0.0063 ........ 0.0069
fix string #4 ........ 0.0105 ........ 0.0253 ...... 0.0083 ........ 0.0077
8-bit string #1 ...... 0.0126 ........ 0.0318 ...... 0.0075 ........ 0.0088
8-bit string #2 ...... 0.0121 ........ 0.0295 ...... 0.0076 ........ 0.0086
8-bit string #3 ...... 0.0125 ........ 0.0293 ...... 0.0130 ........ 0.0093
16-bit string #1 ..... 0.0159 ........ 0.0368 ...... 0.0117 ........ 0.0086
16-bit string #2 ..... 0.1547 ........ 0.1686 ...... 0.1516 ........ 0.1373
32-bit string ........ 0.1558 ........ 0.1729 ...... 0.1511 ........ 0.1396
wide char string #1 .. 0.0098 ........ 0.0237 ...... 0.0066 ........ 0.0065
wide char string #2 .. 0.0128 ........ 0.0291 ...... 0.0061 ........ 0.0082
8-bit binary #1 ........... I ............. I ........... F ............. I
8-bit binary #2 ........... I ............. I ........... F ............. I
8-bit binary #3 ........... I ............. I ........... F ............. I
16-bit binary ............. I ............. I ........... F ............. I
32-bit binary ............. I ............. I ........... F ............. I
fix array #1 ......... 0.0040 ........ 0.0129 ...... 0.0120 ........ 0.0058
fix array #2 ......... 0.0279 ........ 0.0390 ...... 0.0143 ........ 0.0165
fix array #3 ......... 0.0415 ........ 0.0463 ...... 0.0162 ........ 0.0187
16-bit array #1 ...... 0.1349 ........ 0.1628 ...... 0.0334 ........ 0.0341
16-bit array #2 ........... S ............. S ........... S ............. S
32-bit array .............. S ............. S ........... S ............. S
complex array ............. I ............. I ........... F ............. F
fix map #1 ................ I ............. I ........... F ............. I
fix map #2 ........... 0.0345 ........ 0.0391 ...... 0.0143 ........ 0.0168
fix map #3 ................ I ............. I ........... F ............. I
fix map #4 ........... 0.0459 ........ 0.0473 ...... 0.0151 ........ 0.0163
16-bit map #1 ........ 0.2518 ........ 0.2962 ...... 0.0400 ........ 0.0490
16-bit map #2 ............. S ............. S ........... S ............. S
32-bit map ................ S ............. S ........... S ............. S
complex map .......... 0.2380 ........ 0.2682 ...... 0.0545 ........ 0.0579
fixext 1 .................. I ............. I ........... F ............. F
fixext 2 .................. I ............. I ........... F ............. F
fixext 4 .................. I ............. I ........... F ............. F
fixext 8 .................. I ............. I ........... F ............. F
fixext 16 ................. I ............. I ........... F ............. F
8-bit ext ................. I ............. I ........... F ............. F
16-bit ext ................ I ............. I ........... F ............. F
32-bit ext ................ I ............. I ........... F ............. F
32-bit timestamp #1 ....... I ............. I ........... F ............. F
32-bit timestamp #2 ....... I ............. I ........... F ............. F
64-bit timestamp #1 ....... I ............. I ........... F ............. F
64-bit timestamp #2 ....... I ............. I ........... F ............. F
64-bit timestamp #3 ....... I ............. I ........... F ............. F
96-bit timestamp #1 ....... I ............. I ........... F ............. F
96-bit timestamp #2 ....... I ............. I ........... F ............. F
96-bit timestamp #3 ....... I ............. I ........... F ............. F
===========================================================================
Total                  1.5625          2.3866        0.7735          0.7243
Skipped                     4               4             4               4
Failed                      0               0            24              17
Ignored                    24              24             0               7

With JIT:

MP_BENCH_TARGETS=pure_p,pure_u,pecl_p,pecl_u \
php -n -dextension=msgpack.so -dzend_extension=opcache.so \
-dpcre.jit=1 -dopcache.jit_buffer_size=64M -dopcache.jit=tracing -dopcache.enable=1 -dopcache.enable_cli=1 \
tests/bench.php

Example output

Filter: MessagePack\Tests\Perf\Filter\ListFilter
Rounds: 3
Iterations: 100000

===========================================================================
Test/Target            Packer  BufferUnpacker  msgpack_pack  msgpack_unpack
---------------------------------------------------------------------------
nil .................. 0.0001 ........ 0.0052 ...... 0.0053 ........ 0.0042
false ................ 0.0007 ........ 0.0060 ...... 0.0057 ........ 0.0043
true ................. 0.0008 ........ 0.0060 ...... 0.0056 ........ 0.0041
7-bit uint #1 ........ 0.0031 ........ 0.0046 ...... 0.0062 ........ 0.0041
7-bit uint #2 ........ 0.0021 ........ 0.0043 ...... 0.0062 ........ 0.0041
7-bit uint #3 ........ 0.0022 ........ 0.0044 ...... 0.0061 ........ 0.0040
5-bit sint #1 ........ 0.0030 ........ 0.0048 ...... 0.0062 ........ 0.0040
5-bit sint #2 ........ 0.0032 ........ 0.0046 ...... 0.0062 ........ 0.0040
5-bit sint #3 ........ 0.0031 ........ 0.0046 ...... 0.0062 ........ 0.0040
8-bit uint #1 ........ 0.0054 ........ 0.0079 ...... 0.0062 ........ 0.0050
8-bit uint #2 ........ 0.0051 ........ 0.0079 ...... 0.0064 ........ 0.0044
8-bit uint #3 ........ 0.0051 ........ 0.0082 ...... 0.0062 ........ 0.0044
16-bit uint #1 ....... 0.0077 ........ 0.0094 ...... 0.0065 ........ 0.0045
16-bit uint #2 ....... 0.0077 ........ 0.0094 ...... 0.0063 ........ 0.0045
16-bit uint #3 ....... 0.0077 ........ 0.0095 ...... 0.0064 ........ 0.0047
32-bit uint #1 ....... 0.0088 ........ 0.0119 ...... 0.0063 ........ 0.0043
32-bit uint #2 ....... 0.0089 ........ 0.0117 ...... 0.0062 ........ 0.0039
32-bit uint #3 ....... 0.0089 ........ 0.0118 ...... 0.0063 ........ 0.0044
64-bit uint #1 ....... 0.0097 ........ 0.0155 ...... 0.0063 ........ 0.0045
64-bit uint #2 ....... 0.0095 ........ 0.0153 ...... 0.0061 ........ 0.0045
64-bit uint #3 ....... 0.0096 ........ 0.0156 ...... 0.0063 ........ 0.0047
8-bit int #1 ......... 0.0053 ........ 0.0083 ...... 0.0062 ........ 0.0044
8-bit int #2 ......... 0.0052 ........ 0.0080 ...... 0.0062 ........ 0.0044
8-bit int #3 ......... 0.0052 ........ 0.0080 ...... 0.0062 ........ 0.0043
16-bit int #1 ........ 0.0089 ........ 0.0097 ...... 0.0069 ........ 0.0046
16-bit int #2 ........ 0.0075 ........ 0.0093 ...... 0.0063 ........ 0.0043
16-bit int #3 ........ 0.0075 ........ 0.0094 ...... 0.0062 ........ 0.0046
32-bit int #1 ........ 0.0086 ........ 0.0122 ...... 0.0063 ........ 0.0044
32-bit int #2 ........ 0.0087 ........ 0.0120 ...... 0.0066 ........ 0.0046
32-bit int #3 ........ 0.0086 ........ 0.0121 ...... 0.0060 ........ 0.0044
64-bit int #1 ........ 0.0096 ........ 0.0149 ...... 0.0060 ........ 0.0045
64-bit int #2 ........ 0.0096 ........ 0.0157 ...... 0.0062 ........ 0.0044
64-bit int #3 ........ 0.0096 ........ 0.0160 ...... 0.0063 ........ 0.0046
64-bit int #4 ........ 0.0097 ........ 0.0157 ...... 0.0061 ........ 0.0044
64-bit float #1 ...... 0.0079 ........ 0.0153 ...... 0.0056 ........ 0.0044
64-bit float #2 ...... 0.0079 ........ 0.0152 ...... 0.0057 ........ 0.0045
64-bit float #3 ...... 0.0079 ........ 0.0155 ...... 0.0057 ........ 0.0044
fix string #1 ........ 0.0010 ........ 0.0045 ...... 0.0071 ........ 0.0044
fix string #2 ........ 0.0048 ........ 0.0075 ...... 0.0070 ........ 0.0060
fix string #3 ........ 0.0048 ........ 0.0086 ...... 0.0068 ........ 0.0060
fix string #4 ........ 0.0050 ........ 0.0088 ...... 0.0070 ........ 0.0059
8-bit string #1 ...... 0.0081 ........ 0.0129 ...... 0.0069 ........ 0.0062
8-bit string #2 ...... 0.0086 ........ 0.0128 ...... 0.0069 ........ 0.0065
8-bit string #3 ...... 0.0086 ........ 0.0126 ...... 0.0115 ........ 0.0065
16-bit string #1 ..... 0.0105 ........ 0.0137 ...... 0.0128 ........ 0.0068
16-bit string #2 ..... 0.1510 ........ 0.1486 ...... 0.1526 ........ 0.1391
32-bit string ........ 0.1517 ........ 0.1475 ...... 0.1504 ........ 0.1370
wide char string #1 .. 0.0044 ........ 0.0085 ...... 0.0067 ........ 0.0057
wide char string #2 .. 0.0081 ........ 0.0125 ...... 0.0069 ........ 0.0063
8-bit binary #1 ........... I ............. I ........... F ............. I
8-bit binary #2 ........... I ............. I ........... F ............. I
8-bit binary #3 ........... I ............. I ........... F ............. I
16-bit binary ............. I ............. I ........... F ............. I
32-bit binary ............. I ............. I ........... F ............. I
fix array #1 ......... 0.0014 ........ 0.0059 ...... 0.0132 ........ 0.0055
fix array #2 ......... 0.0146 ........ 0.0156 ...... 0.0155 ........ 0.0148
fix array #3 ......... 0.0211 ........ 0.0229 ...... 0.0179 ........ 0.0180
16-bit array #1 ...... 0.0673 ........ 0.0498 ...... 0.0343 ........ 0.0388
16-bit array #2 ........... S ............. S ........... S ............. S
32-bit array .............. S ............. S ........... S ............. S
complex array ............. I ............. I ........... F ............. F
fix map #1 ................ I ............. I ........... F ............. I
fix map #2 ........... 0.0148 ........ 0.0180 ...... 0.0156 ........ 0.0179
fix map #3 ................ I ............. I ........... F ............. I
fix map #4 ........... 0.0252 ........ 0.0201 ...... 0.0214 ........ 0.0167
16-bit map #1 ........ 0.1027 ........ 0.0836 ...... 0.0388 ........ 0.0510
16-bit map #2 ............. S ............. S ........... S ............. S
32-bit map ................ S ............. S ........... S ............. S
complex map .......... 0.1104 ........ 0.1010 ...... 0.0556 ........ 0.0602
fixext 1 .................. I ............. I ........... F ............. F
fixext 2 .................. I ............. I ........... F ............. F
fixext 4 .................. I ............. I ........... F ............. F
fixext 8 .................. I ............. I ........... F ............. F
fixext 16 ................. I ............. I ........... F ............. F
8-bit ext ................. I ............. I ........... F ............. F
16-bit ext ................ I ............. I ........... F ............. F
32-bit ext ................ I ............. I ........... F ............. F
32-bit timestamp #1 ....... I ............. I ........... F ............. F
32-bit timestamp #2 ....... I ............. I ........... F ............. F
64-bit timestamp #1 ....... I ............. I ........... F ............. F
64-bit timestamp #2 ....... I ............. I ........... F ............. F
64-bit timestamp #3 ....... I ............. I ........... F ............. F
96-bit timestamp #1 ....... I ............. I ........... F ............. F
96-bit timestamp #2 ....... I ............. I ........... F ............. F
96-bit timestamp #3 ....... I ............. I ........... F ............. F
===========================================================================
Total                  0.9642          1.0909        0.8224          0.7213
Skipped                     4               4             4               4
Failed                      0               0            24              17
Ignored                    24              24             0               7

Note that the msgpack extension (v2.1.2) doesn't support ext, bin and UTF-8 str types.

License

The library is released under the MIT License. See the bundled LICENSE file for details.

Author: rybakit
Source Code: https://github.com/rybakit/msgpack.php
License: MIT License

#php

Garry Taylor

1669952228

Dijkstra's Algorithm Explained with Examples

In this tutorial, you'll learn: What is Dijkstra's Algorithm and how Dijkstra's algorithm works with the help of visual guides.

You can use algorithms in programming to solve specific problems through a set of precise instructions or procedures.

Dijkstra's algorithm is one of many graph algorithms you'll come across. It is used to find the shortest path from a fixed node to all other nodes in a graph.

There are different representations of Dijkstra's algorithm. You can either find the shortest path between two nodes, or the shortest path from a fixed node to the rest of the nodes in a graph.

In this article, you'll learn how Dijkstra's algorithm works with the help of visual guides.

How Does Dijkstra’s Algorithm Work?

Before we dive into more detailed visual examples, you need to understand how Dijkstra's algorithm works.

Although the theoretical explanation may seem a bit abstract, it'll help you understand the practical aspect better.

In a given graph containing different nodes, we are required to get the shortest path from a given node to the rest of the nodes.

These nodes can represent any object like the names of cities, letters, and so on.

Between each node is a number denoting the distance between two nodes, as you can see in the image below:

nodes-1

We usually work with two arrays – one for visited nodes, and another for unvisited nodes. You'll learn more about the arrays in the next section.

When a node is visited, the algorithm calculates how long it took to get to the node and stores the distance. If a shorter path to a node is found, the initial value assigned for the distance is updated.

Note that a node cannot be visited twice.

The algorithm runs recursively until all the nodes have been visited.

Dijkstra's Algorithm Example

In this section, we'll take a look at a practical example that shows how Dijkstra's algorithm works.

Here's the graph we'll be working with:

nodes

We'll use the table below to put down the visited nodes and their distance from the fixed node:

NODE	SHORTEST DISTANCE FROM FIXED NODE
A	∞
B	∞
C	∞
D	∞
E	∞

Visited nodes = []
Unvisited nodes = [A,B,C,D,E]

Above, we have a table showing each node and the shortest distance from the that node to the fixed node. We are yet to choose the fixed node.

Note that the distance for each node in the table is currently denoted as infinity (∞). This is because we don't know the shortest distance yet.

We also have two arrays – visited and unvisited. Whenever a node is visited, it is added to the visited nodes array.

Let's get started!

To simplify things, I'll break the process down into iterations. You'll see what happens in each step with the aid of diagrams.

Iteration #1

The first iteration might seem confusing, but that's totally fine. Once we start repeating the process in each iteration, you'll have a clearer picture of how the algorithm works.

Step #1 - Pick an unvisited node

We'll choose A as the fixed node. So we'll find the shortest distance from A to every other node in the graph.

node1-1

We're going to give A a distance of 0 because it is the initial node. So the table would look like this:

NODE	SHORTEST DISTANCE FROM FIXED NODE
A	0
B	∞
C	∞
D	∞
E	∞

Step #2 - Find the distance from current node node1a-3

The next thing to do after choosing a node is to find the distance from it to the unvisited nodes around it.

The two unvisited nodes directly linked to A are B and C.

To get the distance from A to B:

0 + 4 = 4

0 being the value of the current node (A), and 4 being the distance between A and B in the graph.

To get the distance from A to C:

0 + 2 = 2

Step #3 - Update table with known distances

In the last step, we got 4 and 2 as the values of B and C respectively. So we'll update the table with those values:

NODE	SHORTEST DISTANCE FROM FIXED NODE
A	0
B	4
C	2
D	∞
E	∞

Step #4 - Update arrays

At this point, the first iteration is complete. We'll move node A to the visited nodes array:

Visited nodes = [A]
Unvisited nodes = [B,C,D,E]

Before we proceed to the next iteration, you should know the following:

Once a node has been visited, it cannot be linked to the current node. Refer to step #2 in the iteration above and step #2 in the next iteration.
A node cannot be visited twice.
You can only update the shortest known distance if you get a value smaller than the recorded distance.

Iteration #2

Step #1 - Pick an unvisited node

We have four unvisited nodes — [B,C,D,E]. So how do you know which node to pick for the next iteration?

Well, we pick the node with the smallest known distance recorded in the table. Here's the table:

NODE	SHORTEST DISTANCE FROM FIXED NODE
A	0
B	4
C	2
D	∞
E	∞

So we're going with node C.

node2-2

Step #2 - Find the distance from current node

To find the distance from the current node to the fixed node, we have to consider the nodes linked to the current node.

The nodes linked to the current node are A and B.

But A has been visited in the previous iteration so it will not be linked to the current node. That is:

node2a-1

From the diagram above,

The green color denotes the current node.
The blue color denotes the visited nodes. We cannot link to them or visit them again.
The red color shows the link from the unvisited nodes to the current node.

To find the distance from C to B:

2 + 1 = 3

2 above is recorded distance for node C while 1 is the distance between C and B in the graph.

Step #3 - Update table with known distances

In the last step, we got the value of B to be 3. In the first iteration, it was 4.

We're going to update the distance in the table to 3.

NODE	SHORTEST DISTANCE FROM FIXED NODE
A	0
B	3
C	2
D	∞
E	∞

So, A --> B = 4 (First iteration).

A --> C --> B = 3 (Second iteration).

The algorithm has helped us find the shortest path to B from A.

Step #4 - Update arrays

We're done with the last visited node. Let's add it to the visited nodes array:

Visited nodes = [A,C]
Unvisited nodes = [B,D,E]

Iteration #3

Step #1 - Pick an unvisited node

We're down to three unvisited nodes — [B,D,E]. From the array, B has the shortest known distance.

node3-2

To restate what is going on in the diagram above:

The green color denotes the current node.
The blue color denotes the visited nodes. We cannot link to them or visit them again.
The red color shows the link from the unvisited nodes to the current node.

Step #2 - Find the distance from current node

The nodes linked to the current node are D and E.

B (the current node) has a value of 3. Therefore,

For node D, 3 + 3 = 6.

For node E, 3 + 2 = 5.

Step #3 - Update table with known distances

NODE	SHORTEST DISTANCE FROM FIXED NODE
A	0
B	3
C	2
D	6
E	5

Step #4 - Update arrays

Visited nodes = [A,C,B]
Unvisited nodes = [D,E]

Iteration #4

Step #1 - Pick an unvisited node

Like other iterations, we'll go with the unvisited node with the shortest known distance. That is E.

node4-1

Step #2 - Find the distance from current node

According to our table, E has a value of 5.

For D in the current iteration,

5 + 5 = 10.

The value gotten for D here is 10, which is greater than the recorded value of 6 in the previous iteration. For this reason, we'll not update the table.

Step #3 - Update table with known distances

Our table remains the same:

NODE	SHORTEST DISTANCE FROM FIXED NODE
A	0
B	3
C	2
D	6
E	5

Step #4 - Update arrays

Visited nodes = [A,C,B,E]
Unvisited nodes = [D]

Iteration #5

Step #1 - Pick an unvisited node

We're currently left with one node in the unvisited array — D.

node5-1

Step #2 - Find the distance from current node

The algorithm has gotten to the last iteration. This is because all nodes linked to the current node have been visited already so we can't link to them.

Step #3 - Update table with known distances

Our table remains the same:

NODE	SHORTEST DISTANCE FROM FIXED NODE
A	0
B	3
C	2
D	6
E	5

At this point, we have updated the table with the shortest distance from the fixed node to every other node in the graph.

Step #4 - Update arrays

Visited nodes = [A,C,B,E,D]
Unvisited nodes = []

As can be seen above, we have no nodes left to visit. Using Dijkstra's algorithm, we've found the shortest distance from the fixed node to others nodes in the graph.

Dijkstra's Algorithm Pseudocode Example

The pseudocode example in this section was gotten from Wikipedia. Here it is:

 1  function Dijkstra(Graph, source):
 2      
 3      for each vertex v in Graph.Vertices:
 4          dist[v] ← INFINITY
 5          prev[v] ← UNDEFINED
 6          add v to Q
 7      dist[source] ← 0
 8      
 9      while Q is not empty:
10          u ← vertex in Q with min dist[u]
11          remove u from Q
12          
13          for each neighbor v of u still in Q:
14              alt ← dist[u] + Graph.Edges(u, v)
15              if alt < dist[v]:
16                  dist[v] ← alt
17                  prev[v] ← u
18
19      return dist[], prev[]

Applications of Dijkstra's Algorithm

Here are some of the common applications of Dijkstra's algorithm:

In maps to get the shortest distance between locations. An example is Google Maps.
In telecommunications to determine transmission rate.
In robotic design to determine shortest path for automated robots.

Summary

In this article, we talked about Dijkstra's algorithm. It is used to find the shortest distance from a fixed node to all other nodes in a graph.

We started by giving a brief summary of how the algorithm works.

We then had a look at an example that further explained Dijkstra's algorithm in steps using visual guides.

We concluded with a pseudocode example and some of the applications of Dijkstra's algorithm.

Happy coding!

Original article source at https://www.freecodecamp.org

#algorithm #datastructures

Ramiro Daugherty

1677907260

Chatgpt-api: Node.js client for the official ChatGPT API

ChatGPT API

Node.js client for the official ChatGPT API.

Intro

This package is a Node.js wrapper around ChatGPT by OpenAI. TS batteries included. ✨

Updates

March 1, 2023

The official OpenAI chat completions API has been released, and it is now the default for this package! 🔥

Method	Free?	Robust?	Quality?
`ChatGPTAPI`	❌ No	✅ Yes	✅️ Real ChatGPT models
`ChatGPTUnofficialProxyAPI`	✅ Yes	☑️ Maybe	✅ Real ChatGPT

Note: We strongly recommend using ChatGPTAPI since it uses the officially supported API from OpenAI. We may remove support for ChatGPTUnofficialProxyAPI in a future release.

ChatGPTAPI - Uses the gpt-3.5-turbo-0301 model with the official OpenAI chat completions API (official, robust approach, but it's not free)
ChatGPTUnofficialProxyAPI - Uses an unofficial proxy server to access ChatGPT's backend API in a way that circumvents Cloudflare (uses the real ChatGPT and is pretty lightweight, but relies on a third-party server and is rate-limited)

CLI

To run the CLI, you'll need an OpenAI API key:

export OPENAI_API_KEY="sk-TODO"
npx chatgpt "your prompt here"

By default, the response is streamed to stdout, the results are stored in a local config file, and every invocation starts a new conversation. You can use -c to continue the previous conversation and --no-stream to disable streaming.

Under the hood, the CLI uses ChatGPTAPI with text-davinci-003 to mimic ChatGPT.

Usage:
  $ chatgpt <prompt>

Commands:
  <prompt>  Ask ChatGPT a question
  rm-cache  Clears the local message cache
  ls-cache  Prints the local message cache path

For more info, run any command with the `--help` flag:
  $ chatgpt --help
  $ chatgpt rm-cache --help
  $ chatgpt ls-cache --help

Options:
  -c, --continue          Continue last conversation (default: false)
  -d, --debug             Enables debug logging (default: false)
  -s, --stream            Streams the response (default: true)
  -s, --store             Enables the local message cache (default: true)
  -t, --timeout           Timeout in milliseconds
  -k, --apiKey            OpenAI API key
  -n, --conversationName  Unique name for the conversation
  -h, --help              Display this message
  -v, --version           Display version number

Install

npm install chatgpt

Make sure you're using node >= 18 so fetch is available (or node >= 14 if you install a fetch polyfill).

Usage

To use this module from Node.js, you need to pick between two methods:

Method	Free?	Robust?	Quality?
`ChatGPTAPI`	❌ No	✅ Yes	✅️ Real ChatGPT models
`ChatGPTUnofficialProxyAPI`	✅ Yes	☑️ Maybe	✅ Real ChatGPT

ChatGPTAPI - Uses the gpt-3.5-turbo-0301 model with the official OpenAI chat completions API (official, robust approach, but it's not free). You can override the model, completion params, and system message to fully customize your assistant.

ChatGPTUnofficialProxyAPI - Uses an unofficial proxy server to access ChatGPT's backend API in a way that circumvents Cloudflare (uses the real ChatGPT and is pretty lightweight, but relies on a third-party server and is rate-limited)

Both approaches have very similar APIs, so it should be simple to swap between them.

Note: We strongly recommend using ChatGPTAPI since it uses the officially supported API from OpenAI. We may remove support for ChatGPTUnofficialProxyAPI in a future release.

Usage - ChatGPTAPI

import { ChatGPTAPI } from 'chatgpt'

async function example() {
  const api = new ChatGPTAPI({
    apiKey: process.env.OPENAI_API_KEY
  })

  const res = await api.sendMessage('Hello World!')
  console.log(res.text)
}

You can override the default model (gpt-3.5-turbo-0301) and any OpenAI chat completion params using completionParams:

const api = new ChatGPTAPI({
  apiKey: process.env.OPENAI_API_KEY,
  completionParams: {
    temperature: 0.5,
    top_p: 0.8
  }
})

If you want to track the conversation, you'll need to pass the parentMessageId like this:

const api = new ChatGPTAPI({ apiKey: process.env.OPENAI_API_KEY })

// send a message and wait for the response
let res = await api.sendMessage('What is OpenAI?')
console.log(res.text)

// send a follow-up
res = await api.sendMessage('Can you expand on that?', {
  parentMessageId: res.id
})
console.log(res.text)

// send another follow-up
res = await api.sendMessage('What were we talking about?', {
  parentMessageId: res.id
})
console.log(res.text)

You can add streaming via the onProgress handler:

const res = await api.sendMessage('Write a 500 word essay on frogs.', {
  // print the partial response as the AI is "typing"
  onProgress: (partialResponse) => console.log(partialResponse.text)
})

// print the full text at the end
console.log(res.text)

You can add a timeout using the timeoutMs option:

// timeout after 2 minutes (which will also abort the underlying HTTP request)
const response = await api.sendMessage(
  'write me a really really long essay on frogs',
  {
    timeoutMs: 2 * 60 * 1000
  }
)

If you want to see more info about what's actually being sent to OpenAI's chat completions API, set the debug: true option in the ChatGPTAPI constructor:

const api = new ChatGPTAPI({
  apiKey: process.env.OPENAI_API_KEY,
  debug: true
})

We default to a basic systemMessage. You can override this in either the ChatGPTAPI constructor or sendMessage:

const res = await api.sendMessage('what is the answer to the universe?', {
  systemMessage: `You are ChatGPT, a large language model trained by OpenAI. You answer as concisely as possible for each responseIf you are generating a list, do not have too many items.
Current date: ${new Date().toISOString()}\n\n`
})

Note that we automatically handle appending the previous messages to the prompt and attempt to optimize for the available tokens (which defaults to 4096).

Usage in CommonJS (Dynamic import)

async function example() {
  // To use ESM in CommonJS, you can use a dynamic import
  const { ChatGPTAPI } = await import('chatgpt')

  const api = new ChatGPTAPI({ apiKey: process.env.OPENAI_API_KEY })

  const res = await api.sendMessage('Hello World!')
  console.log(res.text)
}

Usage - ChatGPTUnofficialProxyAPI

The API for ChatGPTUnofficialProxyAPI is almost exactly the same. You just need to provide a ChatGPT accessToken instead of an OpenAI API key.

import { ChatGPTUnofficialProxyAPI } from 'chatgpt'

async function example() {
  const api = new ChatGPTUnofficialProxyAPI({
    accessToken: process.env.OPENAI_ACCESS_TOKEN
  })

  const res = await api.sendMessage('Hello World!')
  console.log(res.text)
}

See demos/demo-reverse-proxy for a full example:

npx tsx demos/demo-reverse-proxy.ts

ChatGPTUnofficialProxyAPI messages also contain a conversationid in addition to parentMessageId, since the ChatGPT webapp can't reference messages across

Reverse Proxy

You can override the reverse proxy by passing apiReverseProxyUrl:

const api = new ChatGPTUnofficialProxyAPI({
  accessToken: process.env.OPENAI_ACCESS_TOKEN,
  apiReverseProxyUrl: 'https://your-example-server.com/api/conversation'
})

Known reverse proxies run by community members include:

Reverse Proxy URL	Author	Rate Limits	Last Checked
`https://chat.duti.tech/api/conversation`	@acheong08	120 req/min by IP	2/19/2023
`https://gpt.pawan.krd/backend-api/conversation`	@PawanOsman	?	2/19/2023

Note: info on how the reverse proxies work is not being published at this time in order to prevent OpenAI from disabling access.

Access Token

To use ChatGPTUnofficialProxyAPI, you'll need an OpenAI access token from the ChatGPT webapp. To do this, you can use any of the following methods which take an email and password and return an access token:

Node.js libs
Python libs
- acheong08/OpenAIAuth

These libraries work with email + password accounts (e.g., they do not support accounts where you auth via Microsoft / Google).

Alternatively, you can manually get an accessToken by logging in to the ChatGPT webapp and then opening https://chat.openai.com/api/auth/session, which will return a JSON object containing your accessToken string.

Access tokens last for days.

Note: using a reverse proxy will expose your access token to a third-party. There shouldn't be any adverse effects possible from this, but please consider the risks before using this method.

Docs

See the auto-generated docs for more info on methods and parameters.

Demos

Most of the demos use ChatGPTAPI. It should be pretty easy to convert them to use ChatGPTUnofficialProxyAPI if you'd rather use that approach. The only thing that needs to change is how you initialize the api with an accessToken instead of an apiKey.

To run the included demos:

clone repo
install node deps
set OPENAI_API_KEY in .env

A basic demo is included for testing purposes:

npx tsx demos/demo.ts

A demo showing on progress handler:

npx tsx demos/demo-on-progress.ts

The on progress demo uses the optional onProgress parameter to sendMessage to receive intermediary results as ChatGPT is "typing".

A conversation demo:

npx tsx demos/demo-conversation.ts

A persistence demo shows how to store messages in Redis for persistence:

npx tsx demos/demo-persistence.ts

Any keyv adaptor is supported for persistence, and there are overrides if you'd like to use a different way of storing / retrieving messages.

Note that persisting message is required for remembering the context of previous conversations beyond the scope of the current Node.js process, since by default, we only store messages in memory. Here's an external demo of using a completely custom database solution to persist messages.

Note: Persistence is handled automatically when using ChatGPTUnofficialProxyAPI because it is connecting indirectly to ChatGPT.

Projects

All of these awesome projects are built using the chatgpt package. 🤯

Twitter Bot powered by ChatGPT ✨
- Mention @ChatGPTBot on Twitter with your prompt to try it out
ChatGPT API Server - API server for this package with support for multiple OpenAI accounts, proxies, and load-balancing requests between accounts.
ChatGPT Prompts - A collection of 140+ of the best ChatGPT prompts from the community.
Lovelines.xyz
Chrome Extension (demo)
VSCode Extension #1 (demo, updated version, marketplace)
VSCode Extension #2 (marketplace)
VSCode Extension #3 (marketplace)
VSCode Extension #4 (marketplace)
Raycast Extension #1 (demo)
Raycast Extension #2
Telegram Bot #1
Telegram Bot #2
Telegram Bot #3 (group privacy mode, ID-based auth)
Telegram Bot #4 (queue system, ID-based chat thread)
Deno Telegram Bot
Go Telegram Bot
Telegram Bot for YouTube Summaries
GitHub ProBot
Discord Bot #1
Discord Bot #2
Discord Bot #3
Discord Bot #4 (selfbot)
Discord Bot #5
Discord Bot #6 (Shakespeare bot)
WeChat Bot #1
WeChat Bot #2
WeChat Bot #3 (
WeChat Bot #4
WeChat Bot #5
QQ Bot (plugin for Yunzai-bot)
QQ Bot (plugin for KiviBot)
QQ Bot (oicq)
QQ Bot (oicq + RabbitMQ)
QQ Bot (go-cqhttp)
EXM smart contracts
Flutter ChatGPT API
Carik Bot
Github Action for reviewing PRs
WhatsApp Bot #1 (DALL-E + Whisper support 💪)
WhatsApp Bot #2
WhatsApp Bot #3 (multi-user support)
WhatsApp Bot #4 (schedule periodic messages)
WhatsApp Bot #5 (RaspberryPi + ngrok + Twilio)
WhatsApp Bot #6 (Session and chat history storage with MongoStore)
Matrix Bot
Rental Cover Letter Generator
Assistant CLI
Teams Bot
Askai
TalkGPT
ChatGPT With Voice
iOS Shortcut
Slack Bot #1
Slack Bot #2 (with queueing mechanism)
Slack Bot #3
Slack Bot #4 ( Serverless AWS Lambda )
Electron Bot
Kodyfire CLI
Twitch Bot
Continuous Conversation
Figma plugin
NestJS server
NestJS ChatGPT Starter Boilerplate
Wordsmith: Add-in for Microsoft Word
QuizGPT: Create Kahoot quizzes with ChatGPT
openai-chatgpt: Talk to ChatGPT from the terminal
Clippy the Saleforce chatbot ClippyJS joke bot
ai-assistant Chat assistant
Feishu Bot
DomainGPT: Discover available domain names
AI Poem Generator
Next.js ChatGPT With Firebase
ai-commit – GPT-3 Commit Message Generator

If you create a cool integration, feel free to open a PR and add it to the list.

Compatibility

This package is ESM-only.
This package supports node >= 14.
This module assumes that fetch is installed.
- In node >= 18, it's installed by default.
- In node < 18, you need to install a polyfill like unfetch/polyfill (guide) or isomorphic-fetch (guide).
If you want to build a website using chatgpt, we recommend using it only from your backend API

Credits

Huge thanks to @waylaidwanderer, @abacaj, @wong2, @simon300000, @RomanHotsiy, @ElijahPepe, and all the other contributors 💪
The original browser version was inspired by this Go module by Daniel Gross
OpenAI for creating ChatGPT 🔥

Previous Updates

Feb 19, 2023

We now provide three ways of accessing the unofficial ChatGPT API, all of which have tradeoffs:

Method	Free?	Robust?	Quality?
`ChatGPTAPI`	❌ No	✅ Yes	☑️ Mimics ChatGPT
`ChatGPTUnofficialProxyAPI`	✅ Yes	☑️ Maybe	✅ Real ChatGPT
`ChatGPTAPIBrowser` (v3)	✅ Yes	❌ No	✅ Real ChatGPT

Note: I recommend that you use either ChatGPTAPI or ChatGPTUnofficialProxyAPI.

ChatGPTAPI - Uses text-davinci-003 to mimic ChatGPT via the official OpenAI completions API (most robust approach, but it's not free and doesn't use a model fine-tuned for chat)
ChatGPTUnofficialProxyAPI - Uses an unofficial proxy server to access ChatGPT's backend API in a way that circumvents Cloudflare (uses the real ChatGPT and is pretty lightweight, but relies on a third-party server and is rate-limited)
ChatGPTAPIBrowser - (deprecated; v3.5.1 of this package) Uses Puppeteer to access the official ChatGPT webapp (uses the real ChatGPT, but very flaky, heavyweight, and error prone)

Feb 5, 2023

OpenAI has disabled the leaked chat model we were previously using, so we're now defaulting to text-davinci-003, which is not free.

We've found several other hidden, fine-tuned chat models, but OpenAI keeps disabling them, so we're searching for alternative workarounds.

Feb 1, 2023

This package no longer requires any browser hacks – it is now using the official OpenAI completions API with a leaked model that ChatGPT uses under the hood. 🔥

import { ChatGPTAPI } from 'chatgpt'

const api = new ChatGPTAPI({
  apiKey: process.env.OPENAI_API_KEY
})

const res = await api.sendMessage('Hello World!')
console.log(res.text)

Please upgrade to chatgpt@latest (at least v4.0.0). The updated version is significantly more lightweight and robust compared with previous versions. You also don't have to worry about IP issues or rate limiting.

Huge shoutout to @waylaidwanderer for discovering the leaked chat model!

If you run into any issues, we do have a pretty active Discord with a bunch of ChatGPT hackers from the Node.js & Python communities.

Lastly, please consider starring this repo and following me on twitter twitter to help support the project.

Thanks && cheers, Travis

Download Details:

Author: Transitive-bullshit
Source Code: https://github.com/transitive-bullshit/chatgpt-api
License: MIT license

#chatgpt #api #node #AI #openai #chatbot

山本洋介

1642923600

1つの要素を使用してCSSのみのローダーを作成する

Webサイトがある場合は、ローダーを使用すると、ユーザーがリンクまたはボタンをクリックすると何かが起こっていることを知ることができるので便利です。

このローダーコンポーネントは多くの場所で使用でき、可能な限りシンプルにする必要があります。

<div>この投稿では、1行と数行のCSSコードで2種類のローダーを構築する方法を説明します。これだけでなく、同じコードからさまざまなバリエーションを簡単に作成できるようにカスタマイズできるようにします。

これが私たちが構築するものです：

CSSのみのスピナーとプログレスローダー

スピナーローダーを作成する方法

以下は、私たちが構築しているもののデモです。

https://codepen.io/t_afif/pen/PoJyaNy

 <div class="loader"></div>
 <div class="loader" style="--b: 15px;--c: blue;width: 120px;--n: 8"></div>
 <div class="loader" style="--b: 5px;--c: green;width: 80px;--n: 6;--g: 20deg"></div>
 <div class="loader" style="--b: 20px;--c: #000;width: 80px;--n: 15;--g: 7deg"></div>

 .loader {
   --b: 10px;  /* border thickness */
   --n: 10;    /* number of dashes*/
   --g: 10deg; /* gap between dashes*/
   --c: red;   /* the color */

   width: 100px; /* size */
   aspect-ratio: 1;
   border-radius: 50%;
   padding: 1px;
   background: conic-gradient(#0000,var(--c)) content-box;
   -webkit-mask:
     repeating-conic-gradient(#0000 0deg,
        #000 1deg calc(360deg/var(--n) - var(--g) - 1deg),
        #0000     calc(360deg/var(--n) - var(--g)) calc(360deg/var(--n))),
     radial-gradient(farthest-side,#0000 calc(98% - var(--b)),#000 calc(100% - var(--b)));
           mask:
     repeating-conic-gradient(#0000 0deg,
        #000 1deg calc(360deg/var(--n) - var(--g) - 1deg),
        #0000     calc(360deg/var(--n) - var(--g)) calc(360deg/var(--n))),
     radial-gradient(farthest-side,#0000 calc(98% - var(--b)),#000 calc(100% - var(--b)));
   -webkit-mask-composite: destination-in;
           mask-composite: intersect;
   animation: load 1s infinite steps(var(--n));
 }
 @keyframes load {to{transform: rotate(1turn)}}

同じコードを使用する4つの異なるローダーがあります。いくつかの変数を変更するだけで、CSSコードに触れることなく新しいローダーを生成できます。

変数は次のように定義されます。

--b 境界線の太さを定義します。
--n ダッシュの数を定義します。
--gダッシュ間のギャップを定義します。円形の要素を扱っているので、これは角度の値です。
--c 色を定義します。

これは、さまざまな変数を確認するための図です。

スピナーローダーのCSS変数

CSSコードに取り組みましょう。別の図を使用して、ローダーの段階的な構成を説明します。

スピナーローダーのステップバイステップの図

まず、次のような円を作成します。

.loader {
  width: 100px; /* size */
  aspect-ratio: 1;
  border-radius: 50%;
}

これまでのところ複雑なことはありません。これを使用すると、サイズを制御するためにaspect-ratio1つの値（）のみを変更できることに注意してください。width

次に、透明から定義された色（変数--c）に円錐曲線の色を追加します。

.loader {
  width:100px; /* size */
  aspect-ratio: 1;
  border-radius: 50%;
  background: conic-gradient(#0000,var(--c));
}

このステップでmaskは、円の一部を繰り返し非表示にするプロパティを紹介します。--nこれはと--d変数に依存します。図をよく見ると、次のパターンに気付くでしょう。

visible part
invisible part
visible part
invisible part
etc

これを行うには、を使用しますrepeating-conic-gradient(#000 0 X, #0000 0 Y)。から0までXは不透明な色（可視部分）があり、からXまでYは透明な色（不可視部分）があります。

変数を紹介します。

との間の式がになるgように、各可視部分の間に等しいギャップが必要です。XYX = Y - g
n目に見える部分が必要なので、の式YはY = 360deg/nです。完全な円は360deg、単純にで割ったものです。n

これまでのコードは次のとおりです。

.loader {
  width: 100px; /* size */
  aspect-ratio: 1;
  border-radius: 50%;
  background: conic-gradient(#0000,var(--c));
  mask: repeating-conic-gradient(#000 0 calc(360deg/var(--n) - var(--g)) , #0000 0 calc(360deg/var(--n))
}

この次のステップは最も難しいステップです。最終的な形状を取得するために、別のマスクを適用して一種の穴を作成する必要があるためです。これを行うにはradial-gradient()、変数で論理的にaを使用しますb。

radial-gradient(farthest-side,#0000 calc(100% - var(--b)),#000 0)

に等しい厚さを削除するところから完全な円b。

これを前のマスクに追加します。

.loader {
  width: 100px; /* size */
  aspect-ratio: 1;
  border-radius: 50%;
  background: conic-gradient(#0000,var(--c));
  mask: 
   radial-gradient(farthest-side,#0000 calc(100% - var(--b)),#000 0),
   repeating-conic-gradient(#000 0 calc(360deg/var(--n) - var(--g)) , #0000 0 calc(360deg/var(--n))
}

2つのマスクレイヤーがありますが、結果は私たちが望むものではありません。次のようになります。

奇妙に見えるかもしれませんが、それは論理的です。「最終的な」可視部分は、各マスクレイヤーの各可視部分の合計に他なりません。この動作は、を使用して変更できますmask-composite。このプロパティを説明するために記事全体が必要になるので、単純に値を示します。

intersect私たちの場合、（そしてdestination-out接頭辞付きのプロパティについて）考慮する必要があります。コードは次のようになります。

.loader {
  width: 100px; /* size */
  aspect-ratio: 1;
  border-radius: 50%;
  background: conic-gradient(#0000,var(--c));
  mask: 
    radial-gradient(farthest-side,#0000 calc(100% - var(--b)),#000 0),
    repeating-conic-gradient(#000 0 calc(360deg/var(--n) - var(--g)) , #0000 0 calc(360deg/var(--n));
  -webkit-mask-composite: destination-in;
          mask-composite: intersect;
}

形が出来上がりました！アニメーションが欠けているだけです。後者は無限回転です。

注意すべき唯一のことは、stepsアニメーションを使用して、固定されたダッシュと動く色の錯覚を作成しているということです。

これが違いを見るためのイラストです

線形アニメーションとステップアニメーション

最初のものは形状の線形で連続的な回転であり（私たちが望むものではありません）、2番目のものは離散アニメーション（私たちが望むもの）です。

アニメーションを含む完全なコードは次のとおりです。

 <div class="loader"></div>
 <div class="loader" style="--b: 15px;--c: blue;width: 120px;--n: 8"></div>
 <div class="loader" style="--b: 5px;--c: green;width: 80px;--n: 6;--g: 20deg"></div>
 <div class="loader" style="--b: 20px;--c: #000;width: 80px;--n: 15;--g: 7deg"></div>

 .loader {
   --b: 10px;  /* border thickness */
   --n: 10;    /* number of dashes*/
   --g: 10deg; /* gap between dashes*/
   --c: red;   /* the color */

   width: 100px; /* size */
   aspect-ratio: 1;
   border-radius: 50%;
   padding: 1px;
   background: conic-gradient(#0000,var(--c)) content-box;
   -webkit-mask:
     repeating-conic-gradient(#0000 0deg,
        #000 1deg calc(360deg/var(--n) - var(--g) - 1deg),
        #0000     calc(360deg/var(--n) - var(--g)) calc(360deg/var(--n))),
     radial-gradient(farthest-side,#0000 calc(98% - var(--b)),#000 calc(100% - var(--b)));
           mask:
     repeating-conic-gradient(#0000 0deg,
        #000 1deg calc(360deg/var(--n) - var(--g) - 1deg),
        #0000     calc(360deg/var(--n) - var(--g)) calc(360deg/var(--n))),
     radial-gradient(farthest-side,#0000 calc(98% - var(--b)),#000 calc(100% - var(--b)));
   -webkit-mask-composite: destination-in;
           mask-composite: intersect;
   animation: load 1s infinite steps(var(--n));
 }
 @keyframes load {to{transform: rotate(1turn)}}

説明で使用したコードとの違いに気付くでしょう。

padding: 1px背景を追加して設定していますcontent-box
+/1degの色の間にありますrepeating-conic-gradient()
内側の色には数パーセントの違いがあります radial-gradient()

これらは、視覚的な不具合を回避するためのいくつかの修正です。グラデーションは「奇妙な」結果を生成することが知られているため、それらを回避するためにいくつかの値を手動で調整する必要があります。

プログレスローダーを作成する方法

前のローダーと同様に、概要から始めましょう。

https://codepen.io/t_afif/pen/bGoNddg

 <div class="loader"></div>
 <div class="loader" style="--s:10px;--n:10;color:red"></div>
 <div class="loader" style="--g:0px;color:darkblue"></div>
 <div class="loader" style="--s:25px;--g:8px;border-radius:50px;color:green"></div>

 .loader {
   --n:5;    /* control the number of stripes */
   --s:30px; /* control the width of stripes */
   --g:5px;  /* control the gap between stripes */

   width:calc(var(--n)*(var(--s) + var(--g)) - var(--g));
   height:30px;
   padding:var(--g);
   margin:5px auto;
   border:1px solid;
   background:
     repeating-linear-gradient(90deg,
       currentColor  0 var(--s),
       #0000 0 calc(var(--s) + var(--g))
     ) left / calc((var(--n) + 1)*(var(--s) + var(--g))) 100% 
     no-repeat content-box;
   animation: load 1.5s steps(calc(var(--n) + 1)) infinite;
 }
 @keyframes load {
   0% {background-size: 0% 100%}
 }

以前のローダーと同じ構成になっています。ローダーを制御するCSS変数：

--n ダッシュ/ストライプの数を定義します。
--s 各ストライプの幅を定義します。
--g ストライプ間のギャップを定義します。

CSS変数の図

上の図から、要素の幅が3つの変数に依存することがわかります。CSSは次のようになります。

.loader {
  width: calc(var(--n)*(var(--s) + var(--g)) - var(--g));
  height: 30px; /* use any value you want here */
  padding: var(--g);
  border: 1px solid;
}

padding両側にギャップを設定するために使用します。その場合、幅はストライプの数に幅とギャップを掛けたものに等しくなります。Nストライプにはギャップがあるため、1つのギャップを削除しN-1ます。

ストライプを作成するには、以下のグラデーションを使用します。

repeating-linear-gradient(90deg,
  currentColor 0 var(--s),
  #0000        0 calc(var(--s) + var(--g))
 )

From 0tosは定義された色であり、from stos + gは透明色（ギャップ）です。

currentColorプロパティの値であるwhichを使用していcolorます。内部に色を定義しなかったためborder、の値にも使用されることに注意してくださいcolor。ローダーの色を変更したい場合は、colorプロパティを設定するだけです。

これまでのコード：

.loader {
  width: calc(var(--n)*(var(--s) + var(--g)) - var(--g));
  height: 30px;
  padding: var(--g);
  border: 1px solid;
  background:
    repeating-linear-gradient(90deg,
      currentColor  0 var(--s),
      #0000 0 calc(var(--s) + var(--g))
    ) left / 100% 100% content-box no-repeat;
}

content-boxグラデーションがパディング領域をカバーしないようにするために使用しています。100% 100%次に、左の位置に等しいサイズを定義します。

アニメーションの時間です。このローダーでは、background-sizefrom 0% 100%toをアニメーション化します。これは、fromから toへ100% 100%のグラデーションの幅を意味します。0%100%

steps()以前のローダーと同様に、連続的なアニメーションではなく、個別のアニメーションを使用することに依存します。

線形アニメーションとステップアニメーション

2つ目は作成したいもので、次のコードを追加することで実現できます。

.loader {
  animation: load 1.5s steps(var(--n)) infinite;
}
@keyframes load {
  0% {background-size: 0% 100%}
}

最後の図をよく見ると、アニメーションが完全ではないことがわかります。を使用したとしても、最後に1つのストライプがありませんN。これはバグではありませんが、どのように機能するsteps()はずです。

これを克服するには、追加のステップを追加する必要があります。background-sizeグラデーションを増やしてN+1ストライプを含め、を使用しますsteps(N+1)。これにより、最終的なコードが表示されます。

.loader {
  width: calc(var(--n)*(var(--s) + var(--g)) - var(--g));
  height: 30px;
  padding: var(--g);
  margin: 5px auto;
  border: 1px solid;
  background:
    repeating-linear-gradient(90deg,
      currentColor  0 var(--s),
      #0000 0 calc(var(--s) + var(--g))
    ) left / calc((var(--n) + 1)*(var(--s) + var(--g))) 100% 
    content-box no-repeat;
  animation: load 1.5s steps(calc(var(--n) + 1)) infinite;
}
@keyframes load {
  0% {background-size: 0% 100%}
}

グラデーションの幅は、N+1（ではなく100%） 1つのストライプとギャップの幅を掛けたものに等しいことに注意してください。

結論

このチュートリアルを楽しんでいただけたでしょうか。興味があれば、私は500以上のCSSのみのシングルdivローダーを作成しました。また、バックグラウンドプロパティのみを使用してドットローダーを作成する方法を説明する別のチュートリアルを作成しました。

以下の便利なリンクを見つけて、複雑さのために完全には説明しなかった、私が使用したいくつかのプロパティの詳細を確認してください。

mask-composite：https ：//css-tricks.com/mask-compositing-the-crash-course/
steps()：https ：//developer.mozilla.org/en-US/docs/Web/CSS/easing-function#the_steps_class_of_easing_functions

読んでくれてありがとう！

リンク：https ：//www.freecodecamp.org/news/how-to-create-a-css-only-loader/

#css

Adeline McKenzie

1643336880

How to Create a CSS-Only Loader Using One Element

If you have a website, it's helpful to have a loader so users can tell something is happening once they've clicked a link or button.

You can use this loader component in a lot of places, and it should be as simple as possible.

In this post, we will see how to build two types of loaders with only one <div> and a few lines of CSS code. Not only this but we will make them customizable so you can easily create different variations from the same code.

Here's what we'll build:

CSS-only Spinner and Progress Loader

How to Create a Spinner Loader

Below is a demo of what we are building:

https://codepen.io/t_afif/pen/PoJyaNy

 <div class="loader"></div>
 <div class="loader" style="--b: 15px;--c: blue;width: 120px;--n: 8"></div>
 <div class="loader" style="--b: 5px;--c: green;width: 80px;--n: 6;--g: 20deg"></div>
 <div class="loader" style="--b: 20px;--c: #000;width: 80px;--n: 15;--g: 7deg"></div>

 .loader {
   --b: 10px;  /* border thickness */
   --n: 10;    /* number of dashes*/
   --g: 10deg; /* gap between dashes*/
   --c: red;   /* the color */

   width: 100px; /* size */
   aspect-ratio: 1;
   border-radius: 50%;
   padding: 1px;
   background: conic-gradient(#0000,var(--c)) content-box;
   -webkit-mask:
     repeating-conic-gradient(#0000 0deg,
        #000 1deg calc(360deg/var(--n) - var(--g) - 1deg),
        #0000     calc(360deg/var(--n) - var(--g)) calc(360deg/var(--n))),
     radial-gradient(farthest-side,#0000 calc(98% - var(--b)),#000 calc(100% - var(--b)));
           mask:
     repeating-conic-gradient(#0000 0deg,
        #000 1deg calc(360deg/var(--n) - var(--g) - 1deg),
        #0000     calc(360deg/var(--n) - var(--g)) calc(360deg/var(--n))),
     radial-gradient(farthest-side,#0000 calc(98% - var(--b)),#000 calc(100% - var(--b)));
   -webkit-mask-composite: destination-in;
           mask-composite: intersect;
   animation: load 1s infinite steps(var(--n));
 }
 @keyframes load {to{transform: rotate(1turn)}}

We have 4 different loaders using the same code. By only changing a few variables, we can generate a new loader without needing to touch the CSS code.

The variables are defined like below:

--b defines the border thickness.
--n defines the number of dashes.
--g defines the gap between dashes. Since we're dealing with a circular element, this one is an angle value.
--c defines the color.

Here is an illustration to see the different variables.

CSS Variables of the Spinner loader

Let's tackle the CSS code. We will use another figure to illustrate a step-by-step construction of the loader.

Step-by-Step illustration of the Spinner Loader

We first start by creating a circle like this:

.loader {
  width: 100px; /* size */
  aspect-ratio: 1;
  border-radius: 50%;
}

Nothing complex so far. Note the use of aspect-ratio which allows us to only modify one value (the width) in order to control the size.

Then we add a conic gradient coloration from transparent to the defined color (the variable --c):

.loader {
  width:100px; /* size */
  aspect-ratio: 1;
  border-radius: 50%;
  background: conic-gradient(#0000,var(--c));
}

In this step, we introduce the mask property to hide some parts of the circle in a repetitive manner. This will depend on the --n and --d variables. If you look closely at the figure, we will notice the following pattern:

visible part
invisible part
visible part
invisible part
etc

To do this, we use repeating-conic-gradient(#000 0 X, #0000 0 Y). From 0 to X we have an opaque color (visible part) and from X to Y we have a transparent one (invisible part).

We introduce our variables:

We need a gap equal to g between each visible part so the formula between X and Y will be X = Y - g.
We need n visible part so the formula of Y should be Y = 360deg/n. A full circle is 360deg so we simply divide it by n

Our code so far is:

.loader {
  width: 100px; /* size */
  aspect-ratio: 1;
  border-radius: 50%;
  background: conic-gradient(#0000,var(--c));
  mask: repeating-conic-gradient(#000 0 calc(360deg/var(--n) - var(--g)) , #0000 0 calc(360deg/var(--n))
}

This next step is the trickiest one, because we need to apply another mask to create a kind of hole in order to get the final shape. To do this we will logically use a radial-gradient() with our variable b:

radial-gradient(farthest-side,#0000 calc(100% - var(--b)),#000 0)

A full circle from where we remove a thickness equal to b.

We add this to the previous mask:

.loader {
  width: 100px; /* size */
  aspect-ratio: 1;
  border-radius: 50%;
  background: conic-gradient(#0000,var(--c));
  mask: 
   radial-gradient(farthest-side,#0000 calc(100% - var(--b)),#000 0),
   repeating-conic-gradient(#000 0 calc(360deg/var(--n) - var(--g)) , #0000 0 calc(360deg/var(--n))
}

We have two mask layers, but the result is not what we want. We get the following:

It may look strange but it's logical. The "final" visible part is nothing but the sum of each visible part of each mask layer. We can change this behavior using mask-composite. I would need a whole article to explain this property so I will simply give the value.

In our case, we need to consider intersect (and destination-out for the prefixed property). Our code will become:

.loader {
  width: 100px; /* size */
  aspect-ratio: 1;
  border-radius: 50%;
  background: conic-gradient(#0000,var(--c));
  mask: 
    radial-gradient(farthest-side,#0000 calc(100% - var(--b)),#000 0),
    repeating-conic-gradient(#000 0 calc(360deg/var(--n) - var(--g)) , #0000 0 calc(360deg/var(--n));
  -webkit-mask-composite: destination-in;
          mask-composite: intersect;
}

We are done with the shape! We are only missing the animation. The latter is an infinite rotation.

The only thing to note is that I am using a steps animation to create the illusion of fixed dashes and moving colors.

Here is an illustration to see the difference

A Linear Animation vs a Steps Animation

The first one is a linear and continuous rotation of the shape (not what we want) and the second one is a discrete animation (the one we want).

Here is the full code including the animation:

 <div class="loader"></div>
 <div class="loader" style="--b: 15px;--c: blue;width: 120px;--n: 8"></div>
 <div class="loader" style="--b: 5px;--c: green;width: 80px;--n: 6;--g: 20deg"></div>
 <div class="loader" style="--b: 20px;--c: #000;width: 80px;--n: 15;--g: 7deg"></div>

 .loader {
   --b: 10px;  /* border thickness */
   --n: 10;    /* number of dashes*/
   --g: 10deg; /* gap between dashes*/
   --c: red;   /* the color */

   width: 100px; /* size */
   aspect-ratio: 1;
   border-radius: 50%;
   padding: 1px;
   background: conic-gradient(#0000,var(--c)) content-box;
   -webkit-mask:
     repeating-conic-gradient(#0000 0deg,
        #000 1deg calc(360deg/var(--n) - var(--g) - 1deg),
        #0000     calc(360deg/var(--n) - var(--g)) calc(360deg/var(--n))),
     radial-gradient(farthest-side,#0000 calc(98% - var(--b)),#000 calc(100% - var(--b)));
           mask:
     repeating-conic-gradient(#0000 0deg,
        #000 1deg calc(360deg/var(--n) - var(--g) - 1deg),
        #0000     calc(360deg/var(--n) - var(--g)) calc(360deg/var(--n))),
     radial-gradient(farthest-side,#0000 calc(98% - var(--b)),#000 calc(100% - var(--b)));
   -webkit-mask-composite: destination-in;
           mask-composite: intersect;
   animation: load 1s infinite steps(var(--n));
 }
 @keyframes load {to{transform: rotate(1turn)}}

You will notice a few differences with the code I used in the explanation:

I am adding padding: 1px and setting the background to content-box
There is +/1deg between the colors of the repeating-conic-gradient()
There are a few percentages of difference between the color inside the radial-gradient()

Those are some corrections to avoid visual glitches. Gradients are known to produce "strange" results in some cases so we have to adjust some values manually to avoid them.

How to Create a Progress Loader

Like the previous one loader, let's start with an overview:

https://codepen.io/t_afif/pen/bGoNddg

 <div class="loader"></div>
 <div class="loader" style="--s:10px;--n:10;color:red"></div>
 <div class="loader" style="--g:0px;color:darkblue"></div>
 <div class="loader" style="--s:25px;--g:8px;border-radius:50px;color:green"></div>

 .loader {
   --n:5;    /* control the number of stripes */
   --s:30px; /* control the width of stripes */
   --g:5px;  /* control the gap between stripes */

   width:calc(var(--n)*(var(--s) + var(--g)) - var(--g));
   height:30px;
   padding:var(--g);
   margin:5px auto;
   border:1px solid;
   background:
     repeating-linear-gradient(90deg,
       currentColor  0 var(--s),
       #0000 0 calc(var(--s) + var(--g))
     ) left / calc((var(--n) + 1)*(var(--s) + var(--g))) 100% 
     no-repeat content-box;
   animation: load 1.5s steps(calc(var(--n) + 1)) infinite;
 }
 @keyframes load {
   0% {background-size: 0% 100%}
 }

We have the same configuration as the previous loader. CSS variables that control the loader:

--n defines the number of dashes/stripes.
--s defines the width of each stripe.
--g defines the gap between stripes.

Illustration of the CSS Variables

From the above figure we can see that the width of the element will depend on the 3 variables. The CSS will be as follows:

.loader {
  width: calc(var(--n)*(var(--s) + var(--g)) - var(--g));
  height: 30px; /* use any value you want here */
  padding: var(--g);
  border: 1px solid;
}

We use padding to set the gap on each side. Then the width will be equal to the number of stripes multiplied by their width and the gap. We remove one gap because for N stripes we have N-1 gaps.

To create the stripes we will use the below gradient.

repeating-linear-gradient(90deg,
  currentColor 0 var(--s),
  #0000        0 calc(var(--s) + var(--g))
 )

From 0 to s is the defined color and from s to s + g a transparent color (the gap).

I am using currentColor which is the value of the color property. Note that I didn't define any color inside border so it will also use to the value of color. If we want to change the color of the loader, we only need to set the color property.

Our code so far:

.loader {
  width: calc(var(--n)*(var(--s) + var(--g)) - var(--g));
  height: 30px;
  padding: var(--g);
  border: 1px solid;
  background:
    repeating-linear-gradient(90deg,
      currentColor  0 var(--s),
      #0000 0 calc(var(--s) + var(--g))
    ) left / 100% 100% content-box no-repeat;
}

I am using content-box to make sure the gradient doesn't cover the padding area. Then I define a size equal to 100% 100% and a left position.

It's time for the animation. For this loader, we will animate the background-size from 0% 100% to 100% 100% which means the width of our gradient from 0% to 100%

Like the previous loader, we will rely on steps() to have a discrete animation instead of a continuous one.

A Linear Animation vs a Steps Animation

The second one is what we want to create, and we can achieve it by adding the following code:

.loader {
  animation: load 1.5s steps(var(--n)) infinite;
}
@keyframes load {
  0% {background-size: 0% 100%}
}

If you look closely at the last figure, you will notice that the animation is not complete. We are missing one stripe at the end, even if we have used N. This is not a bug but how steps() is supposed to work.

To overcome this, we need to add an extra step. We increase the background-size of our gradient to contain N+1 stripes and use steps(N+1). This will get us to the final code:

.loader {
  width: calc(var(--n)*(var(--s) + var(--g)) - var(--g));
  height: 30px;
  padding: var(--g);
  margin: 5px auto;
  border: 1px solid;
  background:
    repeating-linear-gradient(90deg,
      currentColor  0 var(--s),
      #0000 0 calc(var(--s) + var(--g))
    ) left / calc((var(--n) + 1)*(var(--s) + var(--g))) 100% 
    content-box no-repeat;
  animation: load 1.5s steps(calc(var(--n) + 1)) infinite;
}
@keyframes load {
  0% {background-size: 0% 100%}
}

Note that the width of the gradient is equal to N+1 multiplied by the width of one stripe and a gap (instead of being 100% )

Conclusion

I hope you enjoyed this tutorial. If you are interested, I have made more than 500 CSS-only single div loaders. I also wrote another tutorial to explain how to create the Dots loader using only background properties.

Find below useful links to get more detail about some properties I have used that I didn't explain thoroughly due to their complexity:

mask-composite: https://css-tricks.com/mask-compositing-the-crash-course/
steps(): https://developer.mozilla.org/en-US/docs/Web/CSS/easing-function#the_steps_class_of_easing_functions

Thank you for reading!

Link: https://www.freecodecamp.org/news/how-to-create-a-css-only-loader/

#css