Zilliqa JS: JavaScript SDK for Zilliqa Blockchain

Allows you to interact with the Zilliqa network nodes.

Introduction

zilliqa-js is structured as a Lerna monorepo. Each package roughly corresponds to a discrete ZilliqaModule, most of which can be used independently.

The only required package is @zilliqa-js/core, which contains the default HTTPProvider, and other core abstractions that are necessary for other modules to function.

The following table provides a description of each module and what you may want to use it for.

Package	Version	Description	Dependencies
@zilliqa-js/core		Core abstractions and base classes, such as HTTPProvider and network logic for interfacing with the Zilliqa JSON-RPC.
@zilliqa-js/util		Miscellaneous functions that take care of serialisation/deserialisation and validation.
@zilliqa-js/crypto		Exposes several loosely-coupled cryptographic convenience functions for working with the Zilliqa blockchain and its cryptographic primitives, such as Schnorr signatures.	@zilliqa-js/util
@zilliqa-js/proto		Protobuf source files and corresponding generated JS modules.
@zilliqa-js/account		Wallet, Account and Transaction abstractions.	@zilliqa-js/core, @zilliqa-js/crypto, @zilliqa-js/proto
@zilliqa-js/blockchain		Main interface to the Zilliqa JSON-RPC.	@zilliqa-js/account
@zilliqa-js/contract		Exposes a Contracts module that takes care of smart contract deployment and interaction.	@zilliqa-js/blockchain
@zilliqa-js/subscriptions		Classes to interact with the websocket API of Zilliqa node.
@zilliqa-js/scilla-json-utils		Simplifies the way you construct the Scilla JSON data.
@zilliqa-js/viewblock		Library interfacing with ViewBlock's APIs. This package is maintained by Ashlar	@zilliqa-js/crypto

Package dependency graph

Pre-Requisite (Windows Users)

zilliqa-js uses scrypt library which depends on node-gyp in order to compile the binaries from source on Windows. node-gyp on Windows requires users to install additional Visual Studio Build tools.

To install the required Visual Studio Build tools:

npm install --global --production windows-build-tools # from an elevated PowerShell or CMD.exe as Administrator

npm config set msvs_version 2015 # 2015 is more compatible; though 2017 may work too

Refer to https://github.com/nodejs/node-gyp#installation for more information about node-gyp installation on Windows.

Installation

It is recommended that developers install the JavaScript client by making use of the umbrella package @zilliqa-js/zilliqa. This takes care of bootstrapping the various modules, which are then accessible as members of the Zilliqa class.

npm i @zilliqa-js/zilliqa
# or
yarn add @zilliqa-js/zilliqa

Quick Start

You can create a test account by using Zilliqa Dev Wallet and request funds by using ZIL Faucet service.

const { BN, Long, bytes, units } = require('@zilliqa-js/util');
const { Zilliqa } = require('@zilliqa-js/zilliqa');
const {
  toBech32Address,
  getAddressFromPrivateKey,
} = require('@zilliqa-js/crypto');

const zilliqa = new Zilliqa('https://dev-api.zilliqa.com');

// These are set by the core protocol, and may vary per-chain.
// You can manually pack the bytes according to chain id and msg version.
// For more information: https://apidocs.zilliqa.com/?shell#getnetworkid

const chainId = 333; // chainId of the developer testnet
const msgVersion = 1; // current msgVersion
const VERSION = bytes.pack(chainId, msgVersion);

// Populate the wallet with an account
const privateKey =
  '3375F915F3F9AE35E6B301B7670F53AD1A5BE15D8221EC7FD5E503F21D3450C8';

zilliqa.wallet.addByPrivateKey(privateKey);

const address = getAddressFromPrivateKey(privateKey);
console.log(`My account address is: ${address}`);
console.log(`My account bech32 address is: ${toBech32Address(address)}`);

async function testBlockchain() {
  try {
    // Get Balance
    const balance = await zilliqa.blockchain.getBalance(address);
    // Get Minimum Gas Price from blockchain
    const minGasPrice = await zilliqa.blockchain.getMinimumGasPrice();

    // Account balance (See note 1)
    console.log(`Your account balance is:`);
    console.log(balance.result);
    console.log(`Current Minimum Gas Price: ${minGasPrice.result}`);
    const myGasPrice = units.toQa('2000', units.Units.Li); // Gas Price that will be used by all transactions
    console.log(`My Gas Price ${myGasPrice.toString()}`);
    const isGasSufficient = myGasPrice.gte(new BN(minGasPrice.result)); // Checks if your gas price is less than the minimum gas price
    console.log(`Is the gas price sufficient? ${isGasSufficient}`);

    // Send a transaction to the network
    console.log('Sending a payment transaction to the network...');
    const tx = await zilliqa.blockchain.createTransaction(
      // Notice here we have a default function parameter named toDs which means the priority of the transaction.
      // If the value of toDs is false, then the transaction will be sent to a normal shard, otherwise, the transaction.
      // will be sent to ds shard. More info on design of sharding for smart contract can be found in.
      // https://blog.zilliqa.com/provisioning-sharding-for-smart-contracts-a-design-for-zilliqa-cd8d012ee735.
      // For payment transaction, it should always be false.
      zilliqa.transactions.new(
        {
          version: VERSION,
          toAddr: '0xA54E49719267E8312510D7b78598ceF16ff127CE',
          amount: new BN(units.toQa('1', units.Units.Zil)), // Sending an amount in Zil (1) and converting the amount to Qa
          gasPrice: myGasPrice, // Minimum gasPrice veries. Check the `GetMinimumGasPrice` on the blockchain
          gasLimit: Long.fromNumber(50),
        },
        false,
      ),
    );

    console.log(`The transaction status is:`);
    console.log(tx.receipt);

    // Deploy a contract
    console.log(`Deploying a new contract....`);
    const code = `scilla_version 0

    (* HelloWorld contract *)

    import ListUtils

    (***************************************************)
    (*               Associated library                *)
    (***************************************************)
    library HelloWorld

    let not_owner_code = Int32 1
    let set_hello_code = Int32 2

    (***************************************************)
    (*             The contract definition             *)
    (***************************************************)

    contract HelloWorld
    (owner: ByStr20)

    field welcome_msg : String = ""

    transition setHello (msg : String)
      is_owner = builtin eq owner _sender;
      match is_owner with
      | False =>
        e = {_eventname : "setHello()"; code : not_owner_code};
        event e
      | True =>
        welcome_msg := msg;
        e = {_eventname : "setHello()"; code : set_hello_code};
        event e
      end
    end


    transition getHello ()
        r <- welcome_msg;
        e = {_eventname: "getHello()"; msg: r};
        event e
    end`;

    const init = [
      // this parameter is mandatory for all init arrays
      {
        vname: '_scilla_version',
        type: 'Uint32',
        value: '0',
      },
      {
        vname: 'owner',
        type: 'ByStr20',
        value: `${address}`,
      },
    ];

    // Instance of class Contract
    const contract = zilliqa.contracts.new(code, init);

    // Deploy the contract.
    // Also notice here we have a default function parameter named toDs as mentioned above.
    // A contract can be deployed at either the shard or at the DS. Always set this value to false.
    const [deployTx, hello] = await contract.deploy(
      {
        version: VERSION,
        gasPrice: myGasPrice,
        gasLimit: Long.fromNumber(10000),
      },
      33,
      1000,
      false,
    );

    // Introspect the state of the underlying transaction
    console.log(`Deployment Transaction ID: ${deployTx.id}`);
    console.log(`Deployment Transaction Receipt:`);
    console.log(deployTx.txParams.receipt);

    // Get the deployed contract address
    console.log('The contract address is:');
    console.log(hello.address);
    //Following line added to fix issue https://github.com/Zilliqa/zilliqa-js/issues/168
    const deployedContract = zilliqa.contracts.at(hello.address);

    // Create a new timebased message and call setHello
    // Also notice here we have a default function parameter named toDs as mentioned above.
    // For calling a smart contract, any transaction can be processed in the DS but not every transaction can be processed in the shards.
    // For those transactions are involved in chain call, the value of toDs should always be true.
    // If a transaction of contract invocation is sent to a shard and if the shard is not allowed to process it, then the transaction will be dropped.
    const newMsg = 'Hello, the time is ' + Date.now();
    console.log('Calling setHello transition with msg: ' + newMsg);
    const callTx = await hello.call(
      'setHello',
      [
        {
          vname: 'msg',
          type: 'String',
          value: newMsg,
        },
      ],
      {
        // amount, gasPrice and gasLimit must be explicitly provided
        version: VERSION,
        amount: new BN(0),
        gasPrice: myGasPrice,
        gasLimit: Long.fromNumber(8000),
      },
      33,
      1000,
      false,
    );

    // Retrieving the transaction receipt (See note 2)
    console.log(JSON.stringify(callTx.receipt, null, 4));

    //Get the contract state
    console.log('Getting contract state...');
    const state = await deployedContract.getState();
    console.log('The state of the contract is:');
    console.log(JSON.stringify(state, null, 4));
  } catch (err) {
    console.log(err);
  }
}

testBlockchain();

Notes on the Quick Start script

Note 1: Account balance

The account balance is an object with two fields, balance and nonce.

balance is the account balance in Qa, which is the lowest denomination in Zilliqa. For more information about gas accounting, please refer to here: https://forum.zilliqa.com/t/gas-accounting-in-zilliqa/199

nonce is a counter that keeps track of how many transactions are sent from a given address. In Zilliqa, every transaction sent from an address must have a unique nonce.

{ "balance": "296505000000000", "nonce": "3" }

Note 2: Retrieving transaction receipt

An example of a transaction receipt is this:

{
  "cumulative_gas": 357,
  "epoch_num": "676201",
  "event_logs": [
    {
      "_eventname": "setHello()",
      "address": "0x7a4aa130650396ab7c4006c471576a8404f5092b",
      "params": [
        {
          "type": "Int32",
          "value": "2",
          "vname": "code"
        }
      ]
    }
  ],
  "success": true
}

event_logs comprises of all the events emitted in the transaction. For example, if your transaction calls a transition which emits 3 events, it will be an array of three events. The address is the contract address of the contract which emits the event.

success indicates if the transaction is successful.

Examples

For more examples, visit this repository.

API Documentation

Each package contains API documentation. For convenience, these are links to the respective README documents.

• account
• blockchain
• contract
• core
• crypto
• proto
• util

Also, you can use viewblock library to interface with ViewBlock's APIs.

Development

This repository makes use of several technologies to provide a better and faster development experience for contributors, and has to be bootstrapped before one can do productive work.

Bootstrapping

zilliqa-js leverages Project References, which is available in TypeScript from version 3.x. As such, the build process is slightly different.

# install all dependencies and shared devDependencies
yarn install

# symlink packages, compile TS source files, and generate protobuf files.
yarn bootstrap

# watch TS source files and recompile on change
yarn build:ts -w

Unit Tests

Tests for each package reside in packages/src/*/tests, and are run using jest.

E2E Tests

We can easily simulate a publish using Verdaccio which is a private npm proxy registry. For more details check tasks/local-registry.sh

Bundling

rollup

zilliqa-js is bundled using rollup. To build the distributable bundles, simple run yarn bundle. This will output two bundles, *.umd.js and *.esm.js, to packages/*/dist. Node.js clients are pointed to the umd bundle, and bundlers are pointed to esm.

NOTE: these bundles are not minified.

webpack

To build an all-in-one static js file, first install webpack globally using yarn global add webpack. Then run yarn build:web. This will generate a dist folder in the current path, which contains a file called zilliqa.min.js. It can be used in normal html file. (A more specific example please refer to example/webpack)

NOTE: there may be some issue to install webpack with npm, thus using yarn is a recommended way

Download Details:
Author: Zilliqa
Source Code: https://github.com/Zilliqa/zilliqa-js
License: GPL-3.0 license

#Zilliqa #blockchain #smartcontract #typescript #javascript 

What is GEEK

Buddha Community

NBB: Ad-hoc CLJS Scripting on Node.js

Nbb

Not babashka. Node.js babashka!?

Ad-hoc CLJS scripting on Node.js.

Status

Experimental. Please report issues here.

Goals and features

Nbb's main goal is to make it easy to get started with ad hoc CLJS scripting on Node.js.

Additional goals and features are:

• Fast startup without relying on a custom version of Node.js.
• Small artifact (current size is around 1.2MB).
• First class macros.
• Support building small TUI apps using Reagent.
• Complement babashka with libraries from the Node.js ecosystem.

Requirements

Nbb requires Node.js v12 or newer.

How does this tool work?

CLJS code is evaluated through SCI, the same interpreter that powers babashka. Because SCI works with advanced compilation, the bundle size, especially when combined with other dependencies, is smaller than what you get with self-hosted CLJS. That makes startup faster. The trade-off is that execution is less performant and that only a subset of CLJS is available (e.g. no deftype, yet).

Usage

Install nbb from NPM:

$ npm install nbb -g

Omit -g for a local install.

Try out an expression:

$ nbb -e '(+ 1 2 3)'
6

And then install some other NPM libraries to use in the script. E.g.:

$ npm install csv-parse shelljs zx

Create a script which uses the NPM libraries:

(ns script
  (:require ["csv-parse/lib/sync$default" :as csv-parse]
            ["fs" :as fs]
            ["path" :as path]
            ["shelljs$default" :as sh]
            ["term-size$default" :as term-size]
            ["zx$default" :as zx]
            ["zx$fs" :as zxfs]
            [nbb.core :refer [*file*]]))

(prn (path/resolve "."))

(prn (term-size))

(println (count (str (fs/readFileSync *file*))))

(prn (sh/ls "."))

(prn (csv-parse "foo,bar"))

(prn (zxfs/existsSync *file*))

(zx/$ #js ["ls"])

Call the script:

$ nbb script.cljs
"/private/tmp/test-script"
#js {:columns 216, :rows 47}
510
#js ["node_modules" "package-lock.json" "package.json" "script.cljs"]
#js [#js ["foo" "bar"]]
true
$ ls
node_modules
package-lock.json
package.json
script.cljs

Macros

Nbb has first class support for macros: you can define them right inside your .cljs file, like you are used to from JVM Clojure. Consider the plet macro to make working with promises more palatable:

(defmacro plet
  [bindings & body]
  (let [binding-pairs (reverse (partition 2 bindings))
        body (cons 'do body)]
    (reduce (fn [body [sym expr]]
              (let [expr (list '.resolve 'js/Promise expr)]
                (list '.then expr (list 'clojure.core/fn (vector sym)
                                        body))))
            body
            binding-pairs)))

Using this macro we can look async code more like sync code. Consider this puppeteer example:

(-> (.launch puppeteer)
      (.then (fn [browser]
               (-> (.newPage browser)
                   (.then (fn [page]
                            (-> (.goto page "https://clojure.org")
                                (.then #(.screenshot page #js{:path "screenshot.png"}))
                                (.catch #(js/console.log %))
                                (.then #(.close browser)))))))))

Using plet this becomes:

(plet [browser (.launch puppeteer)
       page (.newPage browser)
       _ (.goto page "https://clojure.org")
       _ (-> (.screenshot page #js{:path "screenshot.png"})
             (.catch #(js/console.log %)))]
      (.close browser))

See the puppeteer example for the full code.

Since v0.0.36, nbb includes promesa which is a library to deal with promises. The above plet macro is similar to promesa.core/let.

Startup time

$ time nbb -e '(+ 1 2 3)'
6
nbb -e '(+ 1 2 3)'   0.17s  user 0.02s system 109% cpu 0.168 total

The baseline startup time for a script is about 170ms seconds on my laptop. When invoked via npx this adds another 300ms or so, so for faster startup, either use a globally installed nbb or use $(npm bin)/nbb script.cljs to bypass npx.

Dependencies

NPM dependencies

Nbb does not depend on any NPM dependencies. All NPM libraries loaded by a script are resolved relative to that script. When using the Reagent module, React is resolved in the same way as any other NPM library.

Classpath

To load .cljs files from local paths or dependencies, you can use the --classpath argument. The current dir is added to the classpath automatically. So if there is a file foo/bar.cljs relative to your current dir, then you can load it via (:require [foo.bar :as fb]). Note that nbb uses the same naming conventions for namespaces and directories as other Clojure tools: foo-bar in the namespace name becomes foo_bar in the directory name.

To load dependencies from the Clojure ecosystem, you can use the Clojure CLI or babashka to download them and produce a classpath:

$ classpath="$(clojure -A:nbb -Spath -Sdeps '{:aliases {:nbb {:replace-deps {com.github.seancorfield/honeysql {:git/tag "v2.0.0-rc5" :git/sha "01c3a55"}}}}}')"

and then feed it to the --classpath argument:

$ nbb --classpath "$classpath" -e "(require '[honey.sql :as sql]) (sql/format {:select :foo :from :bar :where [:= :baz 2]})"
["SELECT foo FROM bar WHERE baz = ?" 2]

Currently nbb only reads from directories, not jar files, so you are encouraged to use git libs. Support for .jar files will be added later.

Current file

The name of the file that is currently being executed is available via nbb.core/*file* or on the metadata of vars:

(ns foo
  (:require [nbb.core :refer [*file*]]))

(prn *file*) ;; "/private/tmp/foo.cljs"

(defn f [])
(prn (:file (meta #'f))) ;; "/private/tmp/foo.cljs"

Reagent

Nbb includes reagent.core which will be lazily loaded when required. You can use this together with ink to create a TUI application:

$ npm install ink

ink-demo.cljs:

(ns ink-demo
  (:require ["ink" :refer [render Text]]
            [reagent.core :as r]))

(defonce state (r/atom 0))

(doseq [n (range 1 11)]
  (js/setTimeout #(swap! state inc) (* n 500)))

(defn hello []
  [:> Text {:color "green"} "Hello, world! " @state])

(render (r/as-element [hello]))

Promesa

Working with callbacks and promises can become tedious. Since nbb v0.0.36 the promesa.core namespace is included with the let and do! macros. An example:

(ns prom
  (:require [promesa.core :as p]))

(defn sleep [ms]
  (js/Promise.
   (fn [resolve _]
     (js/setTimeout resolve ms))))

(defn do-stuff
  []
  (p/do!
   (println "Doing stuff which takes a while")
   (sleep 1000)
   1))

(p/let [a (do-stuff)
        b (inc a)
        c (do-stuff)
        d (+ b c)]
  (prn d))

$ nbb prom.cljs
Doing stuff which takes a while
Doing stuff which takes a while
3

Also see API docs.

Js-interop

Since nbb v0.0.75 applied-science/js-interop is available:

(ns example
  (:require [applied-science.js-interop :as j]))

(def o (j/lit {:a 1 :b 2 :c {:d 1}}))

(prn (j/select-keys o [:a :b])) ;; #js {:a 1, :b 2}
(prn (j/get-in o [:c :d])) ;; 1

Most of this library is supported in nbb, except the following:

• destructuring using :syms
• property access using .-x notation. In nbb, you must use keywords.

See the example of what is currently supported.

Examples

See the examples directory for small examples.

Also check out these projects built with nbb:

• c64core: retrocompute aesthetics twitter bot
• gallery.cljs: script to download walpapers from windowsonearth.org.
• nbb-action-example: example of a Github action built with nbb.

API

See API documentation.

Migrating to shadow-cljs

See this gist on how to convert an nbb script or project to shadow-cljs.

Build

Prequisites:

• babashka >= 0.4.0
• Clojure CLI >= 1.10.3.933
• Node.js 16.5.0 (lower version may work, but this is the one I used to build)

To build:

• Clone and cd into this repo
• bb release

Run bb tasks for more project-related tasks.

Download Details:
Author: borkdude
Download Link: Download The Source Code
Official Website: https://github.com/borkdude/nbb 
License: EPL-1.0

#node #javascript

Zilliqa JS: JavaScript SDK for Zilliqa Blockchain

Allows you to interact with the Zilliqa network nodes.

Introduction

zilliqa-js is structured as a Lerna monorepo. Each package roughly corresponds to a discrete ZilliqaModule, most of which can be used independently.

The only required package is @zilliqa-js/core, which contains the default HTTPProvider, and other core abstractions that are necessary for other modules to function.

The following table provides a description of each module and what you may want to use it for.

Package	Version	Description	Dependencies
@zilliqa-js/core		Core abstractions and base classes, such as HTTPProvider and network logic for interfacing with the Zilliqa JSON-RPC.
@zilliqa-js/util		Miscellaneous functions that take care of serialisation/deserialisation and validation.
@zilliqa-js/crypto		Exposes several loosely-coupled cryptographic convenience functions for working with the Zilliqa blockchain and its cryptographic primitives, such as Schnorr signatures.	@zilliqa-js/util
@zilliqa-js/proto		Protobuf source files and corresponding generated JS modules.
@zilliqa-js/account		Wallet, Account and Transaction abstractions.	@zilliqa-js/core, @zilliqa-js/crypto, @zilliqa-js/proto
@zilliqa-js/blockchain		Main interface to the Zilliqa JSON-RPC.	@zilliqa-js/account
@zilliqa-js/contract		Exposes a Contracts module that takes care of smart contract deployment and interaction.	@zilliqa-js/blockchain
@zilliqa-js/subscriptions		Classes to interact with the websocket API of Zilliqa node.
@zilliqa-js/scilla-json-utils		Simplifies the way you construct the Scilla JSON data.
@zilliqa-js/viewblock		Library interfacing with ViewBlock's APIs. This package is maintained by Ashlar	@zilliqa-js/crypto

Package dependency graph

Pre-Requisite (Windows Users)

zilliqa-js uses scrypt library which depends on node-gyp in order to compile the binaries from source on Windows. node-gyp on Windows requires users to install additional Visual Studio Build tools.

To install the required Visual Studio Build tools:

npm install --global --production windows-build-tools # from an elevated PowerShell or CMD.exe as Administrator

npm config set msvs_version 2015 # 2015 is more compatible; though 2017 may work too

Refer to https://github.com/nodejs/node-gyp#installation for more information about node-gyp installation on Windows.

Installation

It is recommended that developers install the JavaScript client by making use of the umbrella package @zilliqa-js/zilliqa. This takes care of bootstrapping the various modules, which are then accessible as members of the Zilliqa class.

npm i @zilliqa-js/zilliqa
# or
yarn add @zilliqa-js/zilliqa

Quick Start

You can create a test account by using Zilliqa Dev Wallet and request funds by using ZIL Faucet service.

const { BN, Long, bytes, units } = require('@zilliqa-js/util');
const { Zilliqa } = require('@zilliqa-js/zilliqa');
const {
  toBech32Address,
  getAddressFromPrivateKey,
} = require('@zilliqa-js/crypto');

const zilliqa = new Zilliqa('https://dev-api.zilliqa.com');

// These are set by the core protocol, and may vary per-chain.
// You can manually pack the bytes according to chain id and msg version.
// For more information: https://apidocs.zilliqa.com/?shell#getnetworkid

const chainId = 333; // chainId of the developer testnet
const msgVersion = 1; // current msgVersion
const VERSION = bytes.pack(chainId, msgVersion);

// Populate the wallet with an account
const privateKey =
  '3375F915F3F9AE35E6B301B7670F53AD1A5BE15D8221EC7FD5E503F21D3450C8';

zilliqa.wallet.addByPrivateKey(privateKey);

const address = getAddressFromPrivateKey(privateKey);
console.log(`My account address is: ${address}`);
console.log(`My account bech32 address is: ${toBech32Address(address)}`);

async function testBlockchain() {
  try {
    // Get Balance
    const balance = await zilliqa.blockchain.getBalance(address);
    // Get Minimum Gas Price from blockchain
    const minGasPrice = await zilliqa.blockchain.getMinimumGasPrice();

    // Account balance (See note 1)
    console.log(`Your account balance is:`);
    console.log(balance.result);
    console.log(`Current Minimum Gas Price: ${minGasPrice.result}`);
    const myGasPrice = units.toQa('2000', units.Units.Li); // Gas Price that will be used by all transactions
    console.log(`My Gas Price ${myGasPrice.toString()}`);
    const isGasSufficient = myGasPrice.gte(new BN(minGasPrice.result)); // Checks if your gas price is less than the minimum gas price
    console.log(`Is the gas price sufficient? ${isGasSufficient}`);

    // Send a transaction to the network
    console.log('Sending a payment transaction to the network...');
    const tx = await zilliqa.blockchain.createTransaction(
      // Notice here we have a default function parameter named toDs which means the priority of the transaction.
      // If the value of toDs is false, then the transaction will be sent to a normal shard, otherwise, the transaction.
      // will be sent to ds shard. More info on design of sharding for smart contract can be found in.
      // https://blog.zilliqa.com/provisioning-sharding-for-smart-contracts-a-design-for-zilliqa-cd8d012ee735.
      // For payment transaction, it should always be false.
      zilliqa.transactions.new(
        {
          version: VERSION,
          toAddr: '0xA54E49719267E8312510D7b78598ceF16ff127CE',
          amount: new BN(units.toQa('1', units.Units.Zil)), // Sending an amount in Zil (1) and converting the amount to Qa
          gasPrice: myGasPrice, // Minimum gasPrice veries. Check the `GetMinimumGasPrice` on the blockchain
          gasLimit: Long.fromNumber(50),
        },
        false,
      ),
    );

    console.log(`The transaction status is:`);
    console.log(tx.receipt);

    // Deploy a contract
    console.log(`Deploying a new contract....`);
    const code = `scilla_version 0

    (* HelloWorld contract *)

    import ListUtils

    (***************************************************)
    (*               Associated library                *)
    (***************************************************)
    library HelloWorld

    let not_owner_code = Int32 1
    let set_hello_code = Int32 2

    (***************************************************)
    (*             The contract definition             *)
    (***************************************************)

    contract HelloWorld
    (owner: ByStr20)

    field welcome_msg : String = ""

    transition setHello (msg : String)
      is_owner = builtin eq owner _sender;
      match is_owner with
      | False =>
        e = {_eventname : "setHello()"; code : not_owner_code};
        event e
      | True =>
        welcome_msg := msg;
        e = {_eventname : "setHello()"; code : set_hello_code};
        event e
      end
    end


    transition getHello ()
        r <- welcome_msg;
        e = {_eventname: "getHello()"; msg: r};
        event e
    end`;

    const init = [
      // this parameter is mandatory for all init arrays
      {
        vname: '_scilla_version',
        type: 'Uint32',
        value: '0',
      },
      {
        vname: 'owner',
        type: 'ByStr20',
        value: `${address}`,
      },
    ];

    // Instance of class Contract
    const contract = zilliqa.contracts.new(code, init);

    // Deploy the contract.
    // Also notice here we have a default function parameter named toDs as mentioned above.
    // A contract can be deployed at either the shard or at the DS. Always set this value to false.
    const [deployTx, hello] = await contract.deploy(
      {
        version: VERSION,
        gasPrice: myGasPrice,
        gasLimit: Long.fromNumber(10000),
      },
      33,
      1000,
      false,
    );

    // Introspect the state of the underlying transaction
    console.log(`Deployment Transaction ID: ${deployTx.id}`);
    console.log(`Deployment Transaction Receipt:`);
    console.log(deployTx.txParams.receipt);

    // Get the deployed contract address
    console.log('The contract address is:');
    console.log(hello.address);
    //Following line added to fix issue https://github.com/Zilliqa/zilliqa-js/issues/168
    const deployedContract = zilliqa.contracts.at(hello.address);

    // Create a new timebased message and call setHello
    // Also notice here we have a default function parameter named toDs as mentioned above.
    // For calling a smart contract, any transaction can be processed in the DS but not every transaction can be processed in the shards.
    // For those transactions are involved in chain call, the value of toDs should always be true.
    // If a transaction of contract invocation is sent to a shard and if the shard is not allowed to process it, then the transaction will be dropped.
    const newMsg = 'Hello, the time is ' + Date.now();
    console.log('Calling setHello transition with msg: ' + newMsg);
    const callTx = await hello.call(
      'setHello',
      [
        {
          vname: 'msg',
          type: 'String',
          value: newMsg,
        },
      ],
      {
        // amount, gasPrice and gasLimit must be explicitly provided
        version: VERSION,
        amount: new BN(0),
        gasPrice: myGasPrice,
        gasLimit: Long.fromNumber(8000),
      },
      33,
      1000,
      false,
    );

    // Retrieving the transaction receipt (See note 2)
    console.log(JSON.stringify(callTx.receipt, null, 4));

    //Get the contract state
    console.log('Getting contract state...');
    const state = await deployedContract.getState();
    console.log('The state of the contract is:');
    console.log(JSON.stringify(state, null, 4));
  } catch (err) {
    console.log(err);
  }
}

testBlockchain();

Notes on the Quick Start script

Note 1: Account balance

The account balance is an object with two fields, balance and nonce.

balance is the account balance in Qa, which is the lowest denomination in Zilliqa. For more information about gas accounting, please refer to here: https://forum.zilliqa.com/t/gas-accounting-in-zilliqa/199

nonce is a counter that keeps track of how many transactions are sent from a given address. In Zilliqa, every transaction sent from an address must have a unique nonce.

{ "balance": "296505000000000", "nonce": "3" }

Note 2: Retrieving transaction receipt

An example of a transaction receipt is this:

{
  "cumulative_gas": 357,
  "epoch_num": "676201",
  "event_logs": [
    {
      "_eventname": "setHello()",
      "address": "0x7a4aa130650396ab7c4006c471576a8404f5092b",
      "params": [
        {
          "type": "Int32",
          "value": "2",
          "vname": "code"
        }
      ]
    }
  ],
  "success": true
}

event_logs comprises of all the events emitted in the transaction. For example, if your transaction calls a transition which emits 3 events, it will be an array of three events. The address is the contract address of the contract which emits the event.

success indicates if the transaction is successful.

Examples

For more examples, visit this repository.

API Documentation

Each package contains API documentation. For convenience, these are links to the respective README documents.

• account
• blockchain
• contract
• core
• crypto
• proto
• util

Also, you can use viewblock library to interface with ViewBlock's APIs.

Development

This repository makes use of several technologies to provide a better and faster development experience for contributors, and has to be bootstrapped before one can do productive work.

Bootstrapping

zilliqa-js leverages Project References, which is available in TypeScript from version 3.x. As such, the build process is slightly different.

# install all dependencies and shared devDependencies
yarn install

# symlink packages, compile TS source files, and generate protobuf files.
yarn bootstrap

# watch TS source files and recompile on change
yarn build:ts -w

Unit Tests

Tests for each package reside in packages/src/*/tests, and are run using jest.

E2E Tests

We can easily simulate a publish using Verdaccio which is a private npm proxy registry. For more details check tasks/local-registry.sh

Bundling

rollup

zilliqa-js is bundled using rollup. To build the distributable bundles, simple run yarn bundle. This will output two bundles, *.umd.js and *.esm.js, to packages/*/dist. Node.js clients are pointed to the umd bundle, and bundlers are pointed to esm.

NOTE: these bundles are not minified.

webpack

To build an all-in-one static js file, first install webpack globally using yarn global add webpack. Then run yarn build:web. This will generate a dist folder in the current path, which contains a file called zilliqa.min.js. It can be used in normal html file. (A more specific example please refer to example/webpack)

NOTE: there may be some issue to install webpack with npm, thus using yarn is a recommended way

Download Details:
Author: Zilliqa
Source Code: https://github.com/Zilliqa/zilliqa-js
License: GPL-3.0 license

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