read-contract-state.md

description
Read from a smart contract on Arweave

Read Contract State

The readContractState function enables reading the contract state from a deployed contract based on the input parameters.

{% hint style="info" %} To retrieve the result from a contract's read function, it is recommended to utilize the viewContractState function. {% endhint %}

Basic Syntax

The function is called as follows:

import { readContractState } from 'arweavekit/contract'

const readResult = await readContractState({params});

Input Parameters

The following params are available for this function and they must be passed in as an object:

• environment: 'local' | 'testnet' | 'mainnet' : The environment in which the smart contract was created in. The testnet is a pseudo testing environment created on top of the mainnet with the help of custom tags.

{% hint style="info" %} If the contract was created in a local environment, please make sure thatarlocal is running in the background to be able to interact with the contract. To create one, simply run npx arlocal in the command line. Learn more about arlocal here. {% endhint %}

• evaluationOptions : object (optional) : Evaluation options define rules on how a contract will be evaluated during reading contract state. Read more about evaluation options to learn about the available configurations and their uses.
• contractTxId: string : The contractTxId is a unique identifier received upon contract creation. This helps the writeContract to identify the contract to interact with.
• cacheOptions : object (optional) : Contract state is cached for fast retrieval and seamless experience. Custom configurations can be passed in as an object for more control over the caching process. This includes an inMemory option enabling the storage of cache in local memory. By default, the contract state is cached in a database. The dbLocation can be configured with the options outlined in these docs.

Example

const readResult = await readContractState({
      environment: 'testnet',
      contractTxId: 'CONTRACT_TRANSACTION_ID',
});

Returned Data

The function call returns the following data:

readContract: SortKeyCacheResult {
    sortKey: '000000000000,0000000000000,0000000000000000000000000000000000000000000000000000000000000000',
    cachedValue: EvalStateResult {
      state: [Object],
      validity: {},
      errorMessages: {}
    }
},
result: { status: 200, statusText: 'SUCCESSFUL' }

• readContract: SortKeyCacheResult : The readContract object returns the sortKey and cachedValue. Read more here.
  • sortKey: string : The sortKey is a value that warp uses to sort contract transactions.
  • cachedValue: EvalStateResult : The cachedValue is an object that stores the state, the validity of the state and any errors faced while reading the state. If the readContract function is called immediately after a writeContract call, the cached state is optimistically updated assuming the write call occurs successfully, while the interaction continues to be processed on the actual network (in cases of using the testnet and mainnet.
• result: object : The result object returns easy to understand information showing the status of the read call. status: 200 and statusText: 'SUCCESSFUL' indicate that information has been successfully read from the contract.