@aggregion/agrjs

Agrjs

General purpose library for Aggregion blockchain.

Installation

• Install with: npm install @aggregion/agrjs

Usage

Ways to instantiate agrjs.

const Agr = require('@aggregion/agrjs')

// Private key or keys (array) provided statically or by way of a function.
// For multiple keys, the get_required_keys API is used (more on that below).
keyProvider: '5KQwrPbwdL6PhXujxW37FSSQZ1JiwsST4cqQzDeyXtP79zkvFD3'

// Localhost Testnet (run ./docker/up.sh)
const agr = new Agr({keyProvider})

// Connect to a testnet or mainnet
const agr = new Agr({httpEndpoint, chainId, keyProvider})

// Cold-storage
const agr = new Agr({httpEndpoint: null, chainId, keyProvider})

// Read-only instance when 'agrjs' is already a dependency
const agr = new Agr.modules.api({/*config*/})

No-arguments prints usage.

agr.getBlock()

USAGE
getBlock - Fetch a block from the blockchain.

PARAMETERS
{
  "block_num_or_id": "string"
}

All blockchain functions (read and write) follow this pattern:

// If the last argument is a function it is treated as a callback
agr.getBlock(1, (error, result) => {})

// If a callback is not provided, a Promise is returned
agr.getBlock(1) // @returns {Promise}

// Parameters can be positional or an object
agr.getBlock({block_num_or_id: 1})

// An API with no parameters is invoked with an empty object or callback (avoids logging usage)
agr.getInfo({}) // @returns {Promise}
agr.getInfo((error, result) => { console.log(error, result) })

Configuration

const Agr = require('@aggregion/agrjs')

// Default configuration
const config = {
  chainId: null, // 32 byte (64 char) hex string
  keyProvider: ['PrivateKeys...'], // WIF string or array of keys..
  httpEndpoint: 'http://127.0.0.1:8888',
  expireInSeconds: 60,
  broadcast: true,
  verbose: false, // API activity
  sign: true
};

const agr = new Agr(config);

• chainId hex - Unique ID for the blockchain you're connecting to. This is required for valid transaction signing. The chainId is provided via the get_info API call.

  Identifies a chain by its initial genesis block. All transactions signed will only be valid the blockchain with this chainId. Verify the chainId for security reasons.

• keyProvider [array<string>|string|function] - Provides private keys used to sign transaction. If multiple private keys are found, the API get_required_keys is called to discover which signing keys to use. If a function is provided, this function is called for each transaction.

• httpEndpoint string - http or https location of a agrnode server providing a chain API. When using agrjs from a browser remember to configure the same origin policy in agrnode or proxy server. For testing, agrnode configuration access-control-allow-origin = * could be used.

  Set this value to null for a cold-storage (no network) configuration.

• expireInSeconds number - number of seconds before the transaction will expire. The time is based on the agrnode's clock. An unexpired transaction that may have had an error is a liability until the expiration is reached, this time should be brief.

• broadcast [boolean=true] - post the transaction to the blockchain. Use false to obtain a fully signed transaction.

• verbose [boolean=false] - verbose logging such as API activity.

• debug [boolean=false] - low level debug logging (serialization).

• sign [boolean=true] - sign the transaction with a private key. Leaving a transaction unsigned avoids the need to provide a private key.

• mockTransactions (advanced)

  • mockTransactions: () => null // 'pass', or 'fail'
  • pass - do not broadcast, always pretend that the transaction worked
  • fail - do not broadcast, pretend the transaction failed
  • null|undefined - broadcast as usual

• transactionHeaders (advanced) - manually calculate transaction header. This may be provided so agrjs does not need to make header related API calls to agrnode. Used in environments like cold-storage. This callback is called for every transaction.

  • transactionHeaders: (expireInSeconds, callback) => {callback(null/*error*/, headers)}

• logger - default logging configuration.

  logger: {
    log: config.verbose ? console.log : null,  // null to disable
    error: config.verbose ? console.error : null,
  }
  

  For example, redirect error logs: config.logger = {error: (...args) => ..}

Options

Options may be provided after parameters.

NOTE: authorization is for individual actions, it does not belong in Agr(config).

options = {
  authorization: 'alice@active',
  broadcast: true,
  sign: true
}

agr.transfer('alice', 'bob', '1.0000 AGR', '', options)

• authorization [array<auth>|auth] - identifies the signing account and permission typically in a multisig configuration. Authorization may be a string formatted as account@permission or an object<{actor: account, permission}>.

  • If missing default authorizations will be calculated.
  • If provided additional authorizations will not be added.
  • Performs deterministic sorting by account name

  If a default authorization is calculated the action's 1st field must be an account_name. The account_name in the 1st field gets added as the active key authorization for the action.

• broadcast [boolean=true] - post the transaction to the blockchain. Use false to obtain a fully signed transaction.

• sign [boolean=true] - sign the transaction with a private key. Leaving a transaction unsigned avoids the need to provide a private key.

Transaction

The transaction function accepts the standard blockchain transaction.

Required transaction header fields will be added unless you are signing without a network connection (httpEndpoint == null). In that case provide you own headers:

// only needed in cold-storage or for offline transactions
const headers = {
  expiration: '2018-06-14T18:16:10'
  ref_block_num: 1,
  ref_block_prefix: 452435776
}

Create and send (broadcast) a transaction:

/** @return {Promise} */
agr.transaction(
  {
    // ...headers,
    actions: [
      {
        account: 'agrio.token',
        name: 'transfer',
        authorization: [{
          actor: 'inita',
          permission: 'active'
        }],
        data: {
          from: 'inita',
          to: 'initb',
          quantity: '7.0000 AGR',
          memo: ''
        }
      }
    ]
  }
  // config -- example: {broadcast: false, sign: true}
)

Named action functions

More concise functions are provided for applications that may use actions more frequently. This avoids having lots of JSON in the code.

// Run with no arguments to print usage.
agr.transfer()

// Callback is last, when omitted a promise is returned
agr.transfer('inita', 'initb', '1.0000 AGR', '', (error, result) => {})
agr.transfer('inita', 'initb', '1.1000 AGR', '') // @returns {Promise}

// positional parameters
agr.transfer('inita', 'initb', '1.2000 AGR', '')

// named parameters
agr.transfer({from: 'inita', to: 'initb', quantity: '1.3000 AGR', memo: ''})

// options appear after parameters
options = {broadcast: true, sign: true}

// `false` is a shortcut for {broadcast: false}
agr.transfer('inita', 'initb', '1.4000 AGR', '', false)

DecimalPad = Agr.modules.format.DecimalPad
userInput = '10.2'
precision = 4
assert.equal('10.2000', DecimalPad(userInput, precision))

Shorthand

Shorthand is available for some types such as Asset and Authority. This syntax is only for concise functions and does not work when providing entire transaction objects to agr.transaction..

For example:

• permission inita defaults inita@active
• authority 'AGR6MRy..' expands {threshold: 1, keys: [{key: 'AGR6MRy..', weight: 1}]}
• authority inita expands {threshold: 1, accounts: [{permission: {actor: 'inita', permission: 'active'}, weight: 1}]}

New Account

New accounts will likely require some staked tokens for RAM and bandwidth.

wif = '5KQwrPbwdL6PhXujxW37FSSQZ1JiwsST4cqQzDeyXtP79zkvFD3'
pubkey = 'AGR6MRyAjQq8ud7hVNYcfnVPJqcVpscN5So8BhtHuGYqET5GDW5CV'

agr.transaction(tr => {
  tr.newaccount({
    creator: 'agrio',
    name: 'myaccount',
    owner: pubkey,
    active: pubkey
  })

  tr.buyrambytes({
    payer: 'agrio',
    receiver: 'myaccount',
    bytes: 8192
  })

  tr.delegatebw({
    from: 'agrio',
    receiver: 'myaccount',
    stake_net_quantity: '10.0000 AGR',
    stake_cpu_quantity: '10.0000 AGR',
    transfer: 0
  })
})

Contract

Deploy and call smart contracts.

Compile

If you're loading a wasm file, you do not need binaryen. If you're loading a wast file you can include and configure the binaryen compiler, this is used to compile to wasm automatically when calling setcode.

$ npm install binaryen@37.0.0

binaryen = require('binaryen')
const agr = new Agr({keyProvider, binaryen})

Deploy

const wasm = fs.readFileSync(`docker/contracts/agrio.token/agrio.token.wasm`);
const abi = fs.readFileSync(`docker/contracts/agrio.token/agrio.token.abi`);

// Publish contract to the blockchain
agr.setcode('myaccount', 0, 0, wasm) // @returns {Promise}
agr.setabi('myaccount', JSON.parse(abi)) // @returns {Promise}

Fetch a smart contract

// @returns {Promise}
agr.contract('myaccount', [options], [callback])

// Run immediately, `myaction` returns a Promise
agr.contract('myaccount').then(myaccount => myaccount.myaction(..))

// Group actions. `transaction` returns a Promise but `myaction` does not
agr.transaction('myaccount', myaccount => { myaccount.myaction(..) })

// Transaction with multiple contracts
agr.transaction(['myaccount', 'myaccount2'], ({myaccount, myaccount2}) => {
   myaccount.myaction(..)
   myaccount2.myaction(..)
})

Offline or cold-storage contract

const agr = new Agr({httpEndpoint: null})

const abi = fs.readFileSync(`docker/contracts/agrio.token/agrio.token.abi`)
agr.fc.abiCache.abi('myaccount', JSON.parse(abi))

// Check that the ABI is available (print usage)
agr.contract('myaccount').then(myaccount => myaccount.create())

Offline or cold-storage transaction

// ONLINE

// Prepare headers
expireInSeconds = 60 * 60 // 1 hour

const agrio = new Agr(/* {httpEndpoint: 'https://..'} */)

const info = await agr.getInfo({})
const chainDate = new Date(info.head_block_time + 'Z')
let expiration = new Date(chainDate.getTime() + expireInSeconds * 1000)
expiration = expiration.toISOString().split('.')[0]

const block = await agr.getBlock(info.last_irreversible_block_num)

transactionHeaders = {
  expiration,
  ref_block_num: info.last_irreversible_block_num & 0xFFFF,
  ref_block_prefix: block.ref_block_prefix
}

// OFFLINE (bring `transactionHeaders`)

// All keys in keyProvider will sign.
const agr = new Agr({httpEndpoint: null, chainId, keyProvider, transactionHeaders})

transfer = await agr.transfer('inita', 'initb', '1.0000 AGR', '')
transferTransaction = transfer.transaction

// ONLINE (bring `transferTransaction`)

const agr = new Agr(/* {httpEndpoint: 'https://..'} */)

processedTransaction = await agr.pushTransaction(transferTransaction)

Custom Token

// more on the contract / transaction syntax

await agr.transaction('myaccount', myaccount => {

  // Create the initial token with its max supply
  // const options = {authorization: 'myaccount'} // default
  myaccount.create('myaccount', '10000000.000 TOK')//, options)

  // Issue some of the max supply for circulation into an arbitrary account
  myaccount.issue('myaccount', '10000.000 TOK', 'issue')
})

const balance = await agr.getCurrencyBalance('myaccount', 'myaccount', 'TOK')
console.log('Currency Balance', balance)

Calling Actions

Other ways to use contracts and transactions.

// if either transfer fails, both will fail (1 transaction, 2 messages)
await agr.transaction(agr =>
  {
    agr.transfer('inita', 'initb', '1.0000 AGR', ''/*memo*/)
    agr.transfer('inita', 'initc', '1.0000 AGR', ''/*memo*/)
    // Returning a promise is optional (but handled as expected)
  }
  // [options],
  // [callback]
)

// transaction on a single contract
await agr.transaction('myaccount', myaccount => {
  myaccount.transfer('myaccount', 'inita', '10.000 TOK@myaccount', '')
})

// mix contracts in the same transaction
await agr.transaction(['myaccount', 'agrio.token'], ({myaccount, agrio_token}) => {
  myaccount.transfer('inita', 'initb', '1.000 TOK@myaccount', '')
  agrio_token.transfer('inita', 'initb', '1.0000 AGR', '')
})

// The contract method does not take an array so must be called once for
// each contract that is needed.
const myaccount = await agrio.contract('myaccount')
await myaccount.transfer('myaccount', 'inita', '1.000 TOK', '')

// a transaction to a contract instance can specify multiple actions
await myaccount.transaction(myaccountTr => {
  myaccountTr.transfer('inita', 'initb', '1.000 TOK', '')
  myaccountTr.transfer('initb', 'inita', '1.000 TOK', '')
})

Development

From time-to-time the agrks and agrnode binary format will change between releases so you may need to start agrnode with the --skip-transaction-signatures parameter to get your transactions to pass.

Note, package.json has a "main" pointing to ./lib. The ./lib folder is for es2015 code built in a separate step. If you're changing and testing code, import from ./src instead.

new Agr = require('./src')

// forceActionDataHex = false helps transaction readability but may trigger back-end bugs
config = {verbose: true, debug: false, broadcast: true, forceActionDataHex: true, keyProvider}

const agr = new Agr(config)

Fcbuffer

The agr instance can provide serialization:

// 'asset' is a type but could be any struct or type like: transaction or uint8
type = {type: 1, data: '00ff'}
buffer = agr.fc.toBuffer('extensions_type', type)
assert.deepEqual(type, agr.fc.fromBuffer('extensions_type', buffer))

// ABI Serialization
agr.contract('agrio.token', (error, agrio_token) => {
  create = {issuer: 'inita', maximum_supply: '1.0000 AGR'}
  buffer = agrio_token.fc.toBuffer('create', create)
  assert.deepEqual(create, agrio_token.fc.fromBuffer('create', buffer))
})

Use Node v10+ for package-lock.json.

Related Libraries

These libraries are integrated into agrjs seamlessly so you probably do not need to use them directly. They are exported here giving more API access or in some cases may be used standalone.

var {format, api, ecc, json, Fcbuffer} = agr.modules

• format ./format.md

  • Blockchain name validation
  • Asset string formatting

• agrjs-api [Github, NPM]

  • Remote API to an AGR blockchain node (agrnode)
  • Use this library directly if you need read-only access to the blockchain (don't need to sign transactions).

• agrjs-ecc [Github, NPM]

  • Private Key, Public Key, Signature, AES, Encryption / Decryption
  • Validate public or private keys
  • Encrypt or decrypt with AGR compatible checksums
  • Calculate a shared secret

• json {api, schema},

  • Blockchain definitions (api method names, blockchain schema)

• agrjs-keygen [Github, NPM]

  • private key storage and key management

• Fcbuffer [Github, NPM]

  • Binary serialization used by the blockchain
  • Clients sign the binary form of the transaction
  • Allows client to know what it is signing

Environment

Node and browser (es2015)