1576780902
How to Use Celery and RabbitMQ with Django
Celeryis a very asynchronous job queues trong. It is a very good replacement for contabcLinux. Django is Python’s best framework?
About? Celery and Django? documents, you can follow:
Celery: http://docs.celeryproject.org/
Django: https://docs.djangoproject.com/en/2.0/
Note:
Celery 4.0Already supports Django 1.8 and newer versions. For older versions of Django, should use Celery 3.1.
Setup simple Django project
Perform basic Django project creation using the following command:
% mkdir celery-simple
% cd celery-simple
% virtualenv venv -p python3
Running virtualenv with interpreter /Users/minhhahao/.pyenv/versions/3.6.2/bin/python3
Using base prefix '/Users/minhhahao/.pyenv/versions/3.6.2'
New python executable in /Users/minhhahao/workspace/celery-simple/venv/bin/python3
Also creating executable in /Users/minhhahao/workspace/celery-simple/venv/bin/python
Installing setuptools, pip, wheel...done.
% source venv/bin/activatele
(venv) % pip install django==1.9 celery==4.0
Collecting django==1.9
Downloading https://files.pythonhosted.org/packages/ea/9b/b5a6360b3dfcd88d4bad70f59da26cbde4bdec395a31bb26dc840e806a50/Django-1.9-py2.py3-none-any.whl (6.6MB)
100% |████████████████████████████████| 6.6MB 2.2MB/s
Collecting celery==4.0
Downloading https://files.pythonhosted.org/packages/4b/19/745db97793f786644df142f059beea7c784fa3e856758bb5c18891004d49/celery-4.0.0-py2.py3-none-any.whl (395kB)
100% |████████████████████████████████| 399kB 2.2MB/s
Collecting pytz>dev (from celery==4.0)
Downloading https://files.pythonhosted.org/packages/dc/83/15f7833b70d3e067ca91467ca245bae0f6fe56ddc7451aa0dc5606b120f2/pytz-2018.4-py2.py3-none-any.whl (510kB)
100% |████████████████████████████████| 512kB 9.6MB/s
Collecting billiard<3.6.0,>=3.5.0.2 (from celery==4.0)
Downloading https://files.pythonhosted.org/packages/82/55/76f4e786141b7174926cdffa7a155aeea316b729118fb48ec548f3c6754f/billiard-3.5.0.3-py3-none-any.whl (89kB)
100% |████████████████████████████████| 92kB 7.8MB/s
Collecting kombu<5.0,>=4.0 (from celery==4.0)
Downloading https://files.pythonhosted.org/packages/62/a4/5d16954803224a1e451713293c2a028614099f5538cf626e1fdd7b438c86/kombu-4.1.0-py2.py3-none-any.whl (181kB)
100% |████████████████████████████████| 184kB 8.6MB/s
Collecting amqp<3.0,>=2.1.4 (from kombu<5.0,>=4.0->celery==4.0)
Downloading https://files.pythonhosted.org/packages/88/4a/8c45a882d842678963516ebd9cf584a4ded51af719234c3b696c2e884c60/amqp-2.2.2-py2.py3-none-any.whl (48kB)
100% |████████████████████████████████| 51kB 15.6MB/s
Collecting vine>=1.1.3 (from amqp<3.0,>=2.1.4->kombu<5.0,>=4.0->celery==4.0)
Downloading https://files.pythonhosted.org/packages/10/50/5b1ebe42843c19f35edb15022ecae339fbec6db5b241a7a13c924dabf2a3/vine-1.1.4-py2.py3-none-any.whl
Installing collected packages: django, pytz, billiard, vine, amqp, kombu, celery
Successfully installed amqp-2.2.2 billiard-3.5.0.3 celery-4.0.0 django-1.9 kombu-4.1.0 pytz-2018.4 vine-1.1.4
(venv) % django-admin startproject simple
(venv) % cd simple
(venv) % python manage.py startapp ce
Simple project structure:
(venv) % tree
.
├── ce
│ ├── __init__.py
│ ├── admin.py
│ ├── apps.py
│ ├── migrations
│ │ └── __init__.py
│ ├── models.py
│ ├── tests.py
│ └── views.py
├── manage.py
└── simple
├── __init__.py
├── __pycache__
│ ├── __init__.cpython-36.pyc
│ └── settings.cpython-36.pyc
├── settings.py
├── urls.py
└── wsgi.py
4 directories, 14 files
After creating, I created a print print “Hello? World!” on the web:
# simple/settings.py
# Application definition
INSTALLED_APPS = [
'django.contrib.admin',
'django.contrib.auth',
'django.contrib.contenttypes',
'django.contrib.sessions',
'django.contrib.messages',
'django.contrib.staticfiles',
'ce'
]
# simple/urls.py
from django.conf.urls import url, include
from django.contrib import admin
urlpatterns = [
url(r'^admin/', admin.site.urls),
url(r'^', include('ce.urls'))
]
# ce/urls.py
# Create new file `ce/urls.py` to define url of app ce
from django.conf.urls import url
from ce import views
urlpatterns = [
url(r'^$', views.index),
]
# ce/views.py
# Define view
from django.http import HttpResponse
def index(request):
return HttpResponse("Hello World!")
Run server!
(venv) % python manage.py runserver
Performing system checks...
System check identified no issues (0 silenced).
May 03, 2018 - 02:22:31
Django version 1.9, using settings 'simple.settings'
Starting development server at http://127.0.0.1:8000/
Quit the server with CONTROL-C.
Setup a simple celery task
To run Celeryyou need to set up a Redis server or RabbitMQ server. And they are definitely installed
With Redisserver:
# simple/settings.py
REDIS_HOST = 'localhost'
REDIS_PORT = '6379'
BROKER_URL = 'redis://' + REDIS_HOST + ':' + REDIS_PORT + '/0'
With RabbitMQserver:
# simple/settings.py
BROKER_URL = 'amqp://guest:guest@localhost:5672/'
OK, next I create a file to define Celery instance ?:
from __future__ import absolute_import, unicode_literals
import os
from celery import Celery
# set the default Django settings module for the 'celery' program.
os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'simple.settings')
app = Celery('simple')
# Using a string here means the worker doesn't have to serialize
# the configuration object to child processes.
# - namespace='CELERY' means all celery-related configuration keys
# should have a `CELERY_` prefix.
app.config_from_object('django.conf:settings', namespace='CELERY')
# Load task modules from all registered Django app configs.
app.autodiscover_tasks()
@app.task(bind=True)
def debug_task(self):
print('Request: {0!r}'.format(self.request))
Then, import task into simple/__init__.py
# simple/__init__.py
from __future__ import absolute_import, unicode_literals
# This will make sure the app is always imported when
# Django starts so that shared_task will use this app.
from .celery import app as celery_app
__all__ = ['celery_app']
Next, will I create a print task timenow each time the page loads?HelloWorld!. I created a file ce/task.py. The project structure looks like:
(venv) % tree
.
├── ce
│ ├── __init__.py
│ ├── __pycache__
│ │ ├── __init__.cpython-36.pyc
│ │ ├── admin.cpython-36.pyc
│ │ ├── models.cpython-36.pyc
│ │ ├── urls.cpython-36.pyc
│ │ └── views.cpython-36.pyc
│ ├── admin.py
│ ├── apps.py
│ ├── migrations
│ │ ├── __init__.py
│ │ └── __pycache__
│ │ └── __init__.cpython-36.pyc
│ ├── models.py
│ ├── taks.py
│ ├── tests.py
│ ├── urls.py
│ └── views.py
├── db.sqlite3
├── manage.py
└── simple
├── __init__.py
├── __pycache__
│ ├── __init__.cpython-36.pyc
│ ├── celery.cpython-36.pyc
│ ├── settings.cpython-36.pyc
│ ├── urls.cpython-36.pyc
│ └── wsgi.cpython-36.pyc
├── celery.py
├── settings.py
├── urls.py
└── wsgi.py
6 directories, 27 files
Modify file task.py
# ce/taks.py
# Create your tasks here
from celery import shared_task
@shared_task
def add(x, y):
return x + y
@shared_task
def mul(x, y):
return x * y
@shared_task
def xsum(numbers):
return sum(numbers)
To use a combination of Djangoand CeleryI use the django-celery-resultsextension
(venv) % pip install django-celery-results
Collecting django-celery-results
Downloading https://files.pythonhosted.org/packages/8d/82/4ede39c945811ffea9de29c5d312e1ab84352c3b01a290f9dce81614567d/django_celery_results-1.0.1-py2.py3-none-any.whl
Requirement already satisfied: celery<5.0,>=4.0 in /Users/minhhahao/workspace/celery-simple/venv/lib/python3.6/site-packages (from django-celery-results) (4.0.0)
Requirement already satisfied: billiard<3.6.0,>=3.5.0.2 in /Users/minhhahao/workspace/celery-simple/venv/lib/python3.6/site-packages (from celery<5.0,>=4.0->django-celery-results) (3.5.0.3)
Requirement already satisfied: kombu<5.0,>=4.0 in /Users/minhhahao/workspace/celery-simple/venv/lib/python3.6/site-packages (from celery<5.0,>=4.0->django-celery-results) (4.1.0)
Requirement already satisfied: pytz>dev in /Users/minhhahao/workspace/celery-simple/venv/lib/python3.6/site-packages (from celery<5.0,>=4.0->django-celery-results) (2018.4)
Requirement already satisfied: amqp<3.0,>=2.1.4 in /Users/minhhahao/workspace/celery-simple/venv/lib/python3.6/site-packages (from kombu<5.0,>=4.0->celery<5.0,>=4.0->django-celery-results) (2.2.2)
Requirement already satisfied: vine>=1.1.3 in /Users/minhhahao/workspace/celery-simple/venv/lib/python3.6/site-packages (from amqp<3.0,>=2.1.4->kombu<5.0,>=4.0->celery<5.0,>=4.0->django-celery-results) (1.1.4)
Installing collected packages: django-celery-results
Successfully installed django-celery-results-1.0.1
Add django_celery_resultss into simple/settings/.py
# simple/settings.py
INSTALLED_APPS = (
...,
'django_celery_results',
)
Run task:
% celery -A simple worker -l info -B
celery@TEST.local v4.0.0 (latentcall)
Darwin-16.7.0-x86_64-i386-64bit 2018-05-03 03:33:01
[config]
.> app: simple:0x1035f6ba8
.> transport: amqp://guest:**@localhost:5672//
.> results:
.> concurrency: 8 (prefork)
.> task events: OFF (enable -E to monitor tasks in this worker)
[queues]
.> celery exchange=celery(direct) key=celery
[tasks]
. simple.celery.debug_task -> This task defined
[2018-05-03 03:33:01,752: INFO/Beat] beat: Starting...
[2018-05-03 03:33:03,053: INFO/MainProcess] Connected to amqp://guest:**@127.0.0.1:5672//
[2018-05-03 03:33:03,065: INFO/MainProcess] mingle: searching for neighbors
[2018-05-03 03:33:04,085: INFO/MainProcess] mingle: all alone
/Users/minhhahao/.pyenv/versions/3.5.2/lib/python3.5/site-packages/celery/fixups/django.py:202: UserWarning: Using settings.DEBUG leads to a memory leak, never use this setting in production environments!
warnings.warn('Using settings.DEBUG leads to a memory leak, never '
[2018-05-03 03:33:04,107: WARNING/MainProcess] /Users/minhhahao/.pyenv/versions/3.5.2/lib/python3.5/site-packages/celery/fixups/django.py:202: UserWarning: Using settings.DEBUG leads to a memory leak, never use this setting in production environments!
warnings.warn('Using settings.DEBUG leads to a memory leak, never '
[2018-05-03 03:33:04,107: INFO/MainProcess] celery@TEST.local ready.
That’s basically it !!!
Warning:
Sometimes there will be compatibility errors: python, celery, django. Here, I use Python 3.5.2, Celery 4.0, Django 1.9. You need to choose the correct version to avoid errors.
To run? Celerythen you need to make sure? setup Redisor RabbitMQserver to run Asynchronous Thanks for reading!
#python #Django #Celery
What is GEEK
Buddha Community
1667425440
Pdf2gerb: Perl Script Converts PDF Files to Gerber format
pdf2gerb
Perl script converts PDF files to Gerber format
Pdf2Gerb generates Gerber 274X photoplotting and Excellon drill files from PDFs of a PCB. Up to three PDFs are used: the top copper layer, the bottom copper layer (for 2-sided PCBs), and an optional silk screen layer. The PDFs can be created directly from any PDF drawing software, or a PDF print driver can be used to capture the Print output if the drawing software does not directly support output to PDF.
The general workflow is as follows:
- Design the PCB using your favorite CAD or drawing software.
- Print the top and bottom copper and top silk screen layers to a PDF file.
- Run Pdf2Gerb on the PDFs to create Gerber and Excellon files.
- Use a Gerber viewer to double-check the output against the original PCB design.
- Make adjustments as needed.
- Submit the files to a PCB manufacturer.
Please note that Pdf2Gerb does NOT perform DRC (Design Rule Checks), as these will vary according to individual PCB manufacturer conventions and capabilities. Also note that Pdf2Gerb is not perfect, so the output files must always be checked before submitting them. As of version 1.6, Pdf2Gerb supports most PCB elements, such as round and square pads, round holes, traces, SMD pads, ground planes, no-fill areas, and panelization. However, because it interprets the graphical output of a Print function, there are limitations in what it can recognize (or there may be bugs).
See docs/Pdf2Gerb.pdf for install/setup, config, usage, and other info.
pdf2gerb_cfg.pm
#Pdf2Gerb config settings:
#Put this file in same folder/directory as pdf2gerb.pl itself (global settings),
#or copy to another folder/directory with PDFs if you want PCB-specific settings.
#There is only one user of this file, so we don't need a custom package or namespace.
#NOTE: all constants defined in here will be added to main namespace.
#package pdf2gerb_cfg;
use strict; #trap undef vars (easier debug)
use warnings; #other useful info (easier debug)
##############################################################################################
#configurable settings:
#change values here instead of in main pfg2gerb.pl file
use constant WANT_COLORS => ($^O !~ m/Win/); #ANSI colors no worky on Windows? this must be set < first DebugPrint() call
#just a little warning; set realistic expectations:
#DebugPrint("${\(CYAN)}Pdf2Gerb.pl ${\(VERSION)}, $^O O/S\n${\(YELLOW)}${\(BOLD)}${\(ITALIC)}This is EXPERIMENTAL software. \nGerber files MAY CONTAIN ERRORS. Please CHECK them before fabrication!${\(RESET)}", 0); #if WANT_DEBUG
use constant METRIC => FALSE; #set to TRUE for metric units (only affect final numbers in output files, not internal arithmetic)
use constant APERTURE_LIMIT => 0; #34; #max #apertures to use; generate warnings if too many apertures are used (0 to not check)
use constant DRILL_FMT => '2.4'; #'2.3'; #'2.4' is the default for PCB fab; change to '2.3' for CNC
use constant WANT_DEBUG => 0; #10; #level of debug wanted; higher == more, lower == less, 0 == none
use constant GERBER_DEBUG => 0; #level of debug to include in Gerber file; DON'T USE FOR FABRICATION
use constant WANT_STREAMS => FALSE; #TRUE; #save decompressed streams to files (for debug)
use constant WANT_ALLINPUT => FALSE; #TRUE; #save entire input stream (for debug ONLY)
#DebugPrint(sprintf("${\(CYAN)}DEBUG: stdout %d, gerber %d, want streams? %d, all input? %d, O/S: $^O, Perl: $]${\(RESET)}\n", WANT_DEBUG, GERBER_DEBUG, WANT_STREAMS, WANT_ALLINPUT), 1);
#DebugPrint(sprintf("max int = %d, min int = %d\n", MAXINT, MININT), 1);
#define standard trace and pad sizes to reduce scaling or PDF rendering errors:
#This avoids weird aperture settings and replaces them with more standardized values.
#(I'm not sure how photoplotters handle strange sizes).
#Fewer choices here gives more accurate mapping in the final Gerber files.
#units are in inches
use constant TOOL_SIZES => #add more as desired
(
#round or square pads (> 0) and drills (< 0):
.010, -.001, #tiny pads for SMD; dummy drill size (too small for practical use, but needed so StandardTool will use this entry)
.031, -.014, #used for vias
.041, -.020, #smallest non-filled plated hole
.051, -.025,
.056, -.029, #useful for IC pins
.070, -.033,
.075, -.040, #heavier leads
# .090, -.043, #NOTE: 600 dpi is not high enough resolution to reliably distinguish between .043" and .046", so choose 1 of the 2 here
.100, -.046,
.115, -.052,
.130, -.061,
.140, -.067,
.150, -.079,
.175, -.088,
.190, -.093,
.200, -.100,
.220, -.110,
.160, -.125, #useful for mounting holes
#some additional pad sizes without holes (repeat a previous hole size if you just want the pad size):
.090, -.040, #want a .090 pad option, but use dummy hole size
.065, -.040, #.065 x .065 rect pad
.035, -.040, #.035 x .065 rect pad
#traces:
.001, #too thin for real traces; use only for board outlines
.006, #minimum real trace width; mainly used for text
.008, #mainly used for mid-sized text, not traces
.010, #minimum recommended trace width for low-current signals
.012,
.015, #moderate low-voltage current
.020, #heavier trace for power, ground (even if a lighter one is adequate)
.025,
.030, #heavy-current traces; be careful with these ones!
.040,
.050,
.060,
.080,
.100,
.120,
);
#Areas larger than the values below will be filled with parallel lines:
#This cuts down on the number of aperture sizes used.
#Set to 0 to always use an aperture or drill, regardless of size.
use constant { MAX_APERTURE => max((TOOL_SIZES)) + .004, MAX_DRILL => -min((TOOL_SIZES)) + .004 }; #max aperture and drill sizes (plus a little tolerance)
#DebugPrint(sprintf("using %d standard tool sizes: %s, max aper %.3f, max drill %.3f\n", scalar((TOOL_SIZES)), join(", ", (TOOL_SIZES)), MAX_APERTURE, MAX_DRILL), 1);
#NOTE: Compare the PDF to the original CAD file to check the accuracy of the PDF rendering and parsing!
#for example, the CAD software I used generated the following circles for holes:
#CAD hole size: parsed PDF diameter: error:
# .014 .016 +.002
# .020 .02267 +.00267
# .025 .026 +.001
# .029 .03167 +.00267
# .033 .036 +.003
# .040 .04267 +.00267
#This was usually ~ .002" - .003" too big compared to the hole as displayed in the CAD software.
#To compensate for PDF rendering errors (either during CAD Print function or PDF parsing logic), adjust the values below as needed.
#units are pixels; for example, a value of 2.4 at 600 dpi = .0004 inch, 2 at 600 dpi = .0033"
use constant
{
HOLE_ADJUST => -0.004 * 600, #-2.6, #holes seemed to be slightly oversized (by .002" - .004"), so shrink them a little
RNDPAD_ADJUST => -0.003 * 600, #-2, #-2.4, #round pads seemed to be slightly oversized, so shrink them a little
SQRPAD_ADJUST => +0.001 * 600, #+.5, #square pads are sometimes too small by .00067, so bump them up a little
RECTPAD_ADJUST => 0, #(pixels) rectangular pads seem to be okay? (not tested much)
TRACE_ADJUST => 0, #(pixels) traces seemed to be okay?
REDUCE_TOLERANCE => .001, #(inches) allow this much variation when reducing circles and rects
};
#Also, my CAD's Print function or the PDF print driver I used was a little off for circles, so define some additional adjustment values here:
#Values are added to X/Y coordinates; units are pixels; for example, a value of 1 at 600 dpi would be ~= .002 inch
use constant
{
CIRCLE_ADJUST_MINX => 0,
CIRCLE_ADJUST_MINY => -0.001 * 600, #-1, #circles were a little too high, so nudge them a little lower
CIRCLE_ADJUST_MAXX => +0.001 * 600, #+1, #circles were a little too far to the left, so nudge them a little to the right
CIRCLE_ADJUST_MAXY => 0,
SUBST_CIRCLE_CLIPRECT => FALSE, #generate circle and substitute for clip rects (to compensate for the way some CAD software draws circles)
WANT_CLIPRECT => TRUE, #FALSE, #AI doesn't need clip rect at all? should be on normally?
RECT_COMPLETION => FALSE, #TRUE, #fill in 4th side of rect when 3 sides found
};
#allow .012 clearance around pads for solder mask:
#This value effectively adjusts pad sizes in the TOOL_SIZES list above (only for solder mask layers).
use constant SOLDER_MARGIN => +.012; #units are inches
#line join/cap styles:
use constant
{
CAP_NONE => 0, #butt (none); line is exact length
CAP_ROUND => 1, #round cap/join; line overhangs by a semi-circle at either end
CAP_SQUARE => 2, #square cap/join; line overhangs by a half square on either end
CAP_OVERRIDE => FALSE, #cap style overrides drawing logic
};
#number of elements in each shape type:
use constant
{
RECT_SHAPELEN => 6, #x0, y0, x1, y1, count, "rect" (start, end corners)
LINE_SHAPELEN => 6, #x0, y0, x1, y1, count, "line" (line seg)
CURVE_SHAPELEN => 10, #xstart, ystart, x0, y0, x1, y1, xend, yend, count, "curve" (bezier 2 points)
CIRCLE_SHAPELEN => 5, #x, y, 5, count, "circle" (center + radius)
};
#const my %SHAPELEN =
#Readonly my %SHAPELEN =>
our %SHAPELEN =
(
rect => RECT_SHAPELEN,
line => LINE_SHAPELEN,
curve => CURVE_SHAPELEN,
circle => CIRCLE_SHAPELEN,
);
#panelization:
#This will repeat the entire body the number of times indicated along the X or Y axes (files grow accordingly).
#Display elements that overhang PCB boundary can be squashed or left as-is (typically text or other silk screen markings).
#Set "overhangs" TRUE to allow overhangs, FALSE to truncate them.
#xpad and ypad allow margins to be added around outer edge of panelized PCB.
use constant PANELIZE => {'x' => 1, 'y' => 1, 'xpad' => 0, 'ypad' => 0, 'overhangs' => TRUE}; #number of times to repeat in X and Y directions
# Set this to 1 if you need TurboCAD support.
#$turboCAD = FALSE; #is this still needed as an option?
#CIRCAD pad generation uses an appropriate aperture, then moves it (stroke) "a little" - we use this to find pads and distinguish them from PCB holes.
use constant PAD_STROKE => 0.3; #0.0005 * 600; #units are pixels
#convert very short traces to pads or holes:
use constant TRACE_MINLEN => .001; #units are inches
#use constant ALWAYS_XY => TRUE; #FALSE; #force XY even if X or Y doesn't change; NOTE: needs to be TRUE for all pads to show in FlatCAM and ViewPlot
use constant REMOVE_POLARITY => FALSE; #TRUE; #set to remove subtractive (negative) polarity; NOTE: must be FALSE for ground planes
#PDF uses "points", each point = 1/72 inch
#combined with a PDF scale factor of .12, this gives 600 dpi resolution (1/72 * .12 = 600 dpi)
use constant INCHES_PER_POINT => 1/72; #0.0138888889; #multiply point-size by this to get inches
# The precision used when computing a bezier curve. Higher numbers are more precise but slower (and generate larger files).
#$bezierPrecision = 100;
use constant BEZIER_PRECISION => 36; #100; #use const; reduced for faster rendering (mainly used for silk screen and thermal pads)
# Ground planes and silk screen or larger copper rectangles or circles are filled line-by-line using this resolution.
use constant FILL_WIDTH => .01; #fill at most 0.01 inch at a time
# The max number of characters to read into memory
use constant MAX_BYTES => 10 * M; #bumped up to 10 MB, use const
use constant DUP_DRILL1 => TRUE; #FALSE; #kludge: ViewPlot doesn't load drill files that are too small so duplicate first tool
my $runtime = time(); #Time::HiRes::gettimeofday(); #measure my execution time
print STDERR "Loaded config settings from '${\(__FILE__)}'.\n";
1; #last value must be truthful to indicate successful load
#############################################################################################
#junk/experiment:
#use Package::Constants;
#use Exporter qw(import); #https://perldoc.perl.org/Exporter.html
#my $caller = "pdf2gerb::";
#sub cfg
#{
# my $proto = shift;
# my $class = ref($proto) || $proto;
# my $settings =
# {
# $WANT_DEBUG => 990, #10; #level of debug wanted; higher == more, lower == less, 0 == none
# };
# bless($settings, $class);
# return $settings;
#}
#use constant HELLO => "hi there2"; #"main::HELLO" => "hi there";
#use constant GOODBYE => 14; #"main::GOODBYE" => 12;
#print STDERR "read cfg file\n";
#our @EXPORT_OK = Package::Constants->list(__PACKAGE__); #https://www.perlmonks.org/?node_id=1072691; NOTE: "_OK" skips short/common names
#print STDERR scalar(@EXPORT_OK) . " consts exported:\n";
#foreach(@EXPORT_OK) { print STDERR "$_\n"; }
#my $val = main::thing("xyz");
#print STDERR "caller gave me $val\n";
#foreach my $arg (@ARGV) { print STDERR "arg $arg\n"; }Download Details:
Author: swannman
Source Code: https://github.com/swannman/pdf2gerb
License: GPL-3.0 license
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Django admin full Customization step by step
Welcome to my blog , hey everyone in this article you learn how to customize the Django app and view in the article you will know how to register and unregister models from the admin view how to add filtering how to add a custom input field, and a button that triggers an action on all objects and even how to change the look of your app and page using the Django suit package let’s get started.
Database
Custom Titles of Django Admin
Exclude in Django Admin
Fields in Django Admin
#django #create super user django #customize django admin dashboard #django admin #django admin custom field display #django admin customization #django admin full customization #django admin interface #django admin register all models #django customization
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How model queries work in Django
How model queries work in Django
Welcome to my blog, hey everyone in this article we are going to be working with queries in Django so for any web app that you build your going to want to write a query so you can retrieve information from your database so in this article I’ll be showing you all the different ways that you can write queries and it should cover about 90% of the cases that you’ll have when you’re writing your code the other 10% depend on your specific use case you may have to get more complicated but for the most part what I cover in this article should be able to help you so let’s start with the model that I have I’ve already created it.
**Read More : **How to make Chatbot in Python.
Read More : Django Admin Full Customization step by step
let’s just get into this diagram that I made so in here:
Describe each parameter in Django querset
we’re making a simple query for the myModel table so we want to pull out all the information in the database so we have this variable which is gonna hold a return value and we have our myModel models so this is simply the myModel model name so whatever you named your model just make sure you specify that and we’re gonna access the objects attribute once we get that object’s attribute we can simply use the all method and this will return all the information in the database so we’re gonna start with all and then we will go into getting single items filtering that data and go to our command prompt.
Here and we’ll actually start making our queries from here to do this let’s just go ahead and run** Python manage.py shell** and I am in my project file so make sure you’re in there when you start and what this does is it gives us an interactive shell to actually start working with our data so this is a lot like the Python shell but because we did manage.py it allows us to do things a Django way and actually query our database now open up the command prompt and let’s go ahead and start making our first queries.
#django #django model queries #django orm #django queries #django query #model django query #model query #query with django
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What is Django Used For? The Six Most Common Applications | Hacker Noon
Django is a web app framework based upon Python, but is not a part of Python. Python being open-source language, easy to learn and adapt, has become the programming language of choice for beginners as well as seasoned developers in recent years. Django was created to support web application development, web APIs, web services. Thanks to rising popularity of Python, Django too became a framework of choice for python developers.
But, why Django specifically? Why are popular social networking sites, online magazines and e-commerce sites using Django? Why is it so popularly used by developers? Let’s find out what Django is used for.
6 Ways Developers are Using Django
- For scalable web applications
- Django is used for applications with multiple user roles
- For building speedy SaaS applications
- Secure E-commerce and Enterprise applications
- Django is Used for a building low cost MVP
- For building Cross-platform applications
#django #django-in-mvp #django-in-saas #resize-image-in-django #django-tips
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Why should you use Django for Web Development?
Django is a highly powerful framework for building small and large scale web applications. Being a Python-based framework, Django for web development is the preferred choice of companies all over the world.
If you are looking for proof of Django’s popularity, here it is - Django framework for web development is used by YouTube, Dropbox, Instagram, Pinterest, Google, Reddit, and many more. Being an open-source and maintainable web application development framework, companies adore it for building dynamic and sophisticated web applications.
Now you must be asking yourself “is Django good for web development?” The framework has a lot of benefits over other frameworks like Ruby on Rails, Flutter, Xamarin, etc. When you want a robust, scalable and stable application with a large codebase, using Django for web development is the right choice.
Read more: Pros and Cons of Django Web Framework for App Development
What are the advantages of using Django for web development?
Django is admired by web developers all over the world. It is an easy-to-use battery including a framework that doesn’t eat up a lot of time in configuration and setting up the development environment.
The following benefits are your answer to “why use Django for web development”:-
-
Simplicity
Django framework for web development is excellent because of its simplicity and the ease of use. It allows developers to do more than one iteration and make modifications without running the entire code from scratch.
Apart from that, it makes development simpler with its Don’t Repeat Yourself Philosophy, allowing developers to reuse the codebase for creating different components. -
Ecosystem
Django has a rich and diverse development ecosystem. It permits a lot of third-party apps and integrations. While setting up the ide for Django web development, you can use the third-party apps and integrations to add components or blocks in the web application.
From authorization to sending emails, there are apps for some of the most common features. It reduces the time taken to write code for these programs and leads to the timely delivery of products. -
Documentation
Django for web development comes with excellent documentation to develop real-world applications. While other frameworks have alphabetical lists and modules, Django provides quick references to developers for building applications from different stages in the process.
The documentation is updated regularly as Python programmers add new exceptions, rules, and features to the open-source framework. While it is hard to keep it fine-tuned, it is one of the best documentation of a framework. -
Wide community
If you are still asking what are the advantages of using Django for web development, then look at its wide community of developers. Django developers are increasing every day as the framework becomes a popular choice amongst enterprises to fulfill their web application needs.
The community is ready to assist on all Python Django web development projects. There are regular meets, tutorials, and material that can help anyone working with Django. The community regularly answers queries, and you can find the solution to almost any Django problem. -
Libraries
Django allows developers to use massive amounts of libraries for building feature-rich and functional applications. Django REST framework is an excellent library for building Application Programming Interfaces (APIs). Django CMS, Django-allauth, and many other libraries are used for adding functionalities to web applications.
Since the framework uses Python, using libraries becomes an easy task. Python has a lot of libraries with Django integration that enables building quality applications.
Also Read: A Guide to Django Web Development for your Business
Start using Django for web application development
Whether you are looking for an ERP application or a B2C web app, Django framework for web development is the perfect solution. It allows you to develop scalable applications capable of handling heavy traffic load in the future.
You can hire Python developers and Django experts for Python development services from BoTree Technologies who can fulfill your web development needs.
Source: https://www.apsense.com/article/why-should-you-use-django-for-web-development.html
#python development services #django framework #django rest framework #django for web development #django for web development #django