IsBlockhashValid

Checks whether a given blockhash is still valid for transaction submission.

Type: unary

Overview

IsBlockhashValid verifies whether a specific blockhash is still valid for signing and submitting transactions. Solana blockhashes expire after approximately 150 slots (~1 minute), so this check is important before submitting time-sensitive transactions.

HFT systems use this method to pre-validate blockhashes before committing to a transaction, reducing the risk of BlockhashNotFound errors on submission.

Parameters

NameTypeDescription
blockhashstringRequired. The blockhash to validate (base-58 encoded)
commitmentCommitmentLevelOptional. The commitment level

Response

FieldTypeDescription
validboolWhether the blockhash is still valid
slotuint64The slot at which the check was performed

Usage Examples

Node.js

1const grpc = require('@grpc/grpc-js');
2const protoLoader = require('@grpc/proto-loader');
3
4const packageDef = protoLoader.loadSync('geyser.proto', {
5  keepCase: true, longs: String, enums: String, defaults: true, oneofs: true
6});
7const proto = grpc.loadPackageDefinition(packageDef).geyser;
8const client = new proto.Geyser('[IP_ADDRESS]:[PORT]', grpc.credentials.createInsecure());
9
10client.isBlockhashValid({}, (err, response) => {
11  if (err) { console.error(err); return; }
12  console.log('Response:', response);
13});

Rust

1use yellowstone_grpc_proto::geyser::geyser_client::GeyserClient;
2use tonic::transport::Channel;
3
4#[tokio::main]
5async fn main() -> Result<(), Box<dyn std::error::Error>> {
6    let channel = Channel::from_static("http://[IP_ADDRESS]:[PORT]")
7        .connect().await?;
8    let mut client = GeyserClient::new(channel);
9
10    let response = client.isBlockhashValid(tonic::Request::new(())).await?;
11    println!("Response: {:?}", response.into_inner());
12
13    Ok(())
14}