Read Contract

Read smart contract state from the blockchain.

Endpoint

POST /read

Description

Reads smart contract state from the blockchain by calling view functions.

Request Body

{
  "reads": [
    {
      "to": "0xB72F28d9c0f72d488813E57581C17C466855E1F7",
      "funcSignature": "balanceOf(address)",
      "funcParams": ["0x28097eF2268B553783D9c32A33ECb1bB78B209F3"],
      "returnSignature": "uint256",
      "from": "0x28097eF2268B553783D9c32A33ECb1bB78B209F3"
    }
  ],
  "rpc": "https://polygon-amoy.infura.io/v3/{key}"
}

Response

[
  {
    "readIndex": 0,
    "results": ["1000000000000000000"],
    "errors": null
  }
]

Response Fields

readIndex (integer): The index of the read operation in the request array
results (array): The decoded return values from the contract function
errors (string, nullable): Error message if the read operation failed

Example Request

curl -X POST https://api.msa.omnes.tech/read \
  -H "Content-Type: application/json" \
  -d '{
    "reads": [
      {
        "to": "0xB72F28d9c0f72d488813E57581C17C466855E1F7",
        "funcSignature": "balanceOf(address)",
        "funcParams": ["0x28097eF2268B553783D9c32A33ECb1bB78B209F3"],
        "returnSignature": "uint256",
        "from": "0x28097eF2268B553783D9c32A33ECb1bB78B209F3"
      }
    ],
    "rpc": "https://polygon-amoy.infura.io/v3/{key}"
  }'

const response = await fetch('https://api.msa.omnes.tech/read', {
  method: 'POST',
  headers: {
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
    reads: [
      {
        to: '0xB72F28d9c0f72d488813E57581C17C466855E1F7',
        funcSignature: 'balanceOf(address)',
        funcParams: ['0x28097eF2268B553783D9c32A33ECb1bB78B209F3'],
        returnSignature: 'uint256',
        from: '0x28097eF2268B553783D9c32A33ECb1bB78B209F3',
      },
    ],
    rpc: 'https://polygon-amoy.infura.io/v3/{key}',
  }),
});

const result = await response.json();
console.log('Balance:', result[0].results[0]);

import requests

url = "https://api.msa.omnes.tech/read"
payload = {
    "reads": [
        {
            "to": "0xB72F28d9c0f72d488813E57581C17C466855E1F7",
            "funcSignature": "balanceOf(address)",
            "funcParams": ["0x28097eF2268B553783D9c32A33ECb1bB78B209F3"],
            "returnSignature": "uint256",
            "from": "0x28097eF2268B553783D9c32A33ECb1bB78B209F3"
        }
    ],
    "rpc": "https://polygon-amoy.infura.io/v3/{key}"
}

response = requests.post(url, json=payload)
result = response.json()
print(f"Balance: {result[0]['results'][0]}")

Use Cases

Token balances: Check ERC-20 token balances
Contract state: Read any public contract state
Batch reads: Read multiple contract values in a single request
Data validation: Verify contract state before operations

Best Practices

Use correct return signatures: Ensure return signature matches the function return type
Handle errors: Check for errors in the response array
Batch operations: Read multiple values in a single request for efficiency
Validate addresses: Ensure contract addresses are correct

Filter Events - Filter contract events
Get Receipt - Get transaction receipts with decoded logs

💡 Tip: This endpoint only calls view functions and doesn't require gas or signing. Perfect for reading contract state without transactions.

Read Contract

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