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Documentation Index

Fetch the complete documentation index at: https://docs.polygon.technology/llms.txt

Use this file to discover all available pages before exploring further.

The Matic.js library follows common api architecture throughout and the APIs are divided into two types:
  1. Read API
  2. Write API

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Read API

Read methods do not publish anything on blockchain, so they do not consume any gas. For example: 
const erc20 = posClient.erc20('<token address>');
const balance = await erc20.getBalance('<user address>')
Read methods are very simple and return results directly.

​
Write API

Write methods publish some data on the blockchain, so they consumes gas. Example of write methods are approve, deposit etc. A write method returns (at least) two data items:
  1. TransactionHash
  2. TransactionReceipt
For example: 
// get a contract object
const erc20 = posClient.erc20('<token address>');

// send the transaction
const result = await erc20.approve(10);

// get transaction hash

const txHash = await result.getTransactionHash();

// get receipt

const receipt = await result.getReceipt();

​
Transaction option

There are some configurable options that are available for all API’s. These configurations can be passed as parameters. Available configurations are -
  • from?: string | number - The address transactions should be made from.
  • to?: string - The address transactions should be made to.
  • value?: number | string | BN - The value transferred for the transaction in wei.
  • gasLimit?: number | string - The maximum gas provided for a transaction (gas limit).
  • gasPrice?: number | string | BN - The gas price in wei to use for transactions.
  • data?: string - The byte code of the contract.
  • nonce?: number;
  • chainId?: number;
  • chain?: string;
  • hardfork?: string;
  • returnTransaction?: boolean - making it true will return the transaction object which can be used to send transaction manually.
This example configures the gas price: 
// get a contract object
const erc20RootToken = posClient.erc20(<root token address>,true);

// approve 100 amount
const approveResult = await erc20Token.approve(100, {
    gasPrice: '4000000000',
});

const txHash = await approveResult.getTransactionHash();

const txReceipt = await approveResult.getReceipt();