eth_newFilter

Creates a filter object, based on filter options, to notify when the state changes (logs). To check if the state has changed, call eth_getFilterChanges.

A note on specifying topic filters:

Topics are order-dependent. A transaction with a log with topics [A, B] will be matched by the following topic filters:

• [] "anything"
• [A] "A in first position (and anything after)"
• [null, B] "anything in first position AND B in second position (and anything after)"
• [A, B] "A in first position AND B in second position (and anything after)"
• [[A, B], [A, B]] "(A OR B) in first position AND (A OR B) in second position (and anything after)"

Parameters

1. Object - The filter options:

• fromBlock: QUANTITY|TAG - (optional, default: "latest") Integer block number, or "latest" for the last mined block or "pending", "earliest" for not yet mined transactions.
• toBlock: QUANTITY|TAG - (optional, default: "latest") Integer block number, or "latest" for the last mined block or "pending", "earliest" for not yet mined transactions.
• address: DATA|Array, 20 Bytes - (optional) Contract address or a list of addresses from which logs should originate.
• topics: Array of DATA, - (optional) Array of 32 Bytes DATA topics. Topics are order-dependent. Each topic can also be an array of DATA with "or" options.

Example Parameters

params: [{
  "fromBlock": "0x1",
  "toBlock": "0x2",
  "address": "0x8888f1f195afa192cfee860698584c030f4c9db1",
  "topics": ["0x000000000000000000000000a94f5374fce5edbc8e2a8697c15331677e6ebf0b", null, ["0x000000000000000000000000a94f5374fce5edbc8e2a8697c15331677e6ebf0b", "0x0000000000000000000000000aff3454fce5edbc8cca8697c15331677e6ebccc"]]
}]

Returns

QUANTITY - A filter id.

Example

// Request
curl -X POST --data '{"jsonrpc":"2.0","method":"eth_newFilter","params":[{"topics":["0x0000000000000000000000000000000000000000000000000000000012341234"]}],"id":73}'

// Result
{
  "id":1,
  "jsonrpc": "2.0",
  "result": "0x1" // 1
}