Install package

# npm
npm install codechain-sdk
# yarn
yarn add codechain-sdk

Usage examples

Make sure that your CodeChain RPC server is listening. In the examples, we assume that it is localhost:8080

Setup the test account

Before you begin to meet various examples, you need to setup the account. The given account below(tccqzn9jjm3j6qg69smd7cn0eup4w7z2yu9my9a2k78) holds 100000 CCC at the genesis block. It's a sufficient amount to pay for the parcel fee.

var SDK = require("codechain-sdk");
var sdk = new SDK({ server: "http://localhost:8080" });

var secret = "ede1d4ccb4ec9a8bbbae9a13db3f4a7b56ea04189be86ac3a6a439d9a0a1addd";
var passphrase = "satoshi";
sdk.rpc.account.importRaw(secret, passphrase).then(function (account) {
    console.log(account); // tccqzn9jjm3j6qg69smd7cn0eup4w7z2yu9my9a2k78
});

Get the latest block number

You can retrieve the chain information using methods in sdk.rpc.chain.

var SDK = require("codechain-sdk");
var sdk = new SDK({ server: "http://localhost:8080" });

sdk.rpc.chain.getBestBlockNumber().then(function (num) {
    console.log(num);
});

Create a new account with a private key

var SDK = require("codechain-sdk");

var secret = SDK.util.generatePrivateKey();
console.log("Your secret:", secret);

var account = SDK.util.getAccountIdFromPrivate(secret);
var address = SDK.Key.classes.PlatformAddress.fromAccountId(account);
console.log("Your CodeChain address:", address.toString());

Create a new account with RPC

You can manage accounts and create their signatures using methods in sdk.rpc.account.

var SDK = require("codechain-sdk");
var sdk = new SDK({ server: "http://localhost:8080" });

var passphrase = "my-secret";
sdk.rpc.account.create(passphrase).then(function (account) {
    console.log(account); // string that starts with "ccc". For example: tccqzn9jjm3j6qg69smd7cn0eup4w7z2yu9my9a2k78
});

Get the balance of an account

You can get the balance of an account using getBalance method in sdk.rpc.chain. See also getNonce, getRegularKey.

var SDK = require("codechain-sdk");
var sdk = new SDK({ server: "http://localhost:8080" });

sdk.rpc.chain.getBalance("tccqzn9jjm3j6qg69smd7cn0eup4w7z2yu9my9a2k78").then(function (balance) {
    // the balance is a U256 instance at this moment. Use toString() to print it out.
    console.log(balance.toString()); // the amount of CCC that the account has.
});

Send a payment parcel via sendParcel

When you create an account, the CCC balance is 0. CCC is needed to pay for the parcel's fee. The fee must be at least 10 for any parcel. The example below shows the sending of 10000 CCC from the test account(tccqzn..9a2k78) to the account(tccqru..7vzngg).

var SDK = require("codechain-sdk");
var sdk = new SDK({ server: "http://localhost:8080" });

var parcel = sdk.core.createPaymentParcel({
    recipient: "tccqruq09sfgax77nj4gukjcuq69uzeyv0jcs7vzngg",
    amount: 10000
});

sdk.rpc.chain.sendParcel(parcel, {
    account: "tccqzn9jjm3j6qg69smd7cn0eup4w7z2yu9my9a2k78",
    passphrase: "satoshi"
}).then(function (parcelHash) {
    return sdk.rpc.chain.getParcelInvoice(parcelHash, { timeout: 300 * 1000 });
}).then(function (parcelInvoice) {
    console.log(parcelInvoice) // { success: true }
});

Send a payment parcel via sendSignedParcel

var SDK = require("codechain-sdk");

var sdk = new SDK({ server: "http://localhost:8080" });

var parcel = sdk.core.createPaymentParcel({
    recipient: "tccqruq09sfgax77nj4gukjcuq69uzeyv0jcs7vzngg",
    amount: 10000,
});

var account = "tccqzn9jjm3j6qg69smd7cn0eup4w7z2yu9my9a2k78";
var accountSecret = "ede1d4ccb4ec9a8bbbae9a13db3f4a7b56ea04189be86ac3a6a439d9a0a1addd";

sdk.rpc.chain.getNonce(account).then(function (nonce) {
    return sdk.rpc.chain.sendSignedParcel(parcel.sign({
        secret: accountSecret,
        fee: 10,
        nonce: nonce,
    }));
}).then(function (parcelHash) {
    return sdk.rpc.chain.getParcelInvoice(parcelHash, { timeout: 300 * 1000 });
}).then(function (parcelInvoice) {
    console.log(parcelInvoice) // { success: true }
});

Create an asset transfer address

var SDK = require("codechain-sdk");
var sdk = new SDK({ server: "http://localhost:8080" });

// createRemoteKeyStore("http://localhost:7007") is also available.
// If you want to know how to set up the external key store, go to
// https://codechain.readthedocs.io/en/latest/asset-management.html#use-remotekeystore-to-save-asset-address-private-key
sdk.key.createLocalKeyStore()
    .then(function (keyStore) {
        // P2PKH supports P2PKH(Pay to Public Key Hash) lock/unlock scripts.
        var p2pkh = sdk.key.createP2PKH({ keyStore });
        return p2pkh.createAddress();
    })
    .then(function (address) {
        // This type of address is used to receive assets when minting or transferring them.
        // Example: tcaqqq9pgkq69z488qlkvhkpcxcgfd3cqlkzgxyq9cewxuda8qqz7jtlvctt5eze
        console.log(address.toString());
    })

Mint a new asset

var SDK = require("codechain-sdk");
var sdk = new SDK({ server: "http://localhost:8080" });

// If you want to know how to create an address, see the example "Create an
// asset transfer address".
var address = "tcaqqq9pgkq69z488qlkvhkpcxcgfd3cqlkzgxyq9cewxuda8qqz7jtlvctt5eze";

var assetMintTransaction = sdk.core.createAssetMintTransaction({
    scheme: {
        shardId: 0,
        metadata: JSON.stringify({
            name: "Silver Coin",
            description: "...",
            icon_url: "...",
        }),
        amount: 100000000,
    },
    recipient: address,
});

// Send a change-shard-state parcel to process the transaction.
var parcel = sdk.core.createChangeShardStateParcel({ transactions: [assetMintTransaction] });
sdk.rpc.chain.sendParcel(parcel, {
    account: "tccqzn9jjm3j6qg69smd7cn0eup4w7z2yu9my9a2k78",
    passphrase: "satoshi"
}).then(function (parcelHash) {
    // Get the invoice of the parcel.
    return sdk.rpc.chain.getParcelInvoice(parcelHash, {
        // Wait up to 120 seconds to get the invoice.
        timeout: 120 * 1000
    });
}).then(function (invoice) {
    // The invoice of change-shard-state parcel is an array of the object that has
    // type { success: boolean }. Each object represents the result of each
    // transaction.
    console.log(invoice); // [{ success: true }]
});

Transfer assets

A brief version of the example will be uploaded soon. The entire example can be viewed here.

SDK modules

RPC
- node
- chain
- network
- account
Core
- classes (Block, Parcel, Transaction, ...)
Utility

CodeChain JavaScript SDK

Table of Contents