Solana: Error: failed to get recent blockhash: TypeError: fetch failed in Anchor test

Error: Failed to Get Recent Block Hash on Solana using Anchor Test

The error message “TypeError: fetch failed in Anchor test” indicates that the Anchor testing library is unable to retrieve a recent block hash from the Solana network. This issue can arise due to various reasons, including changes in the RPC (Remote Procedure Call) interface or compatibility issues with the fetch method.

In this article, we will explore possible solutions to resolve the error and successfully obtain recent block hashes on Solana using Anchor.

What is a Block Hash?

A block hash is a unique digital fingerprint of a block in a blockchain. It represents a specific transaction and is used to track the history of transactions on the network.

RPC Interface Changes: A Potential Cause

The fetch method has undergone changes in recent RPC interfaces, which may impact the way you access block hashes. Anchor uses a different API than some other testing libraries, such as Web3.py or solana-api. To resolve this issue, you can try the following:

• Update Anchor to the latest version: Ensure that your Anchor installation is up-to-date with the latest version.

• Check the RPC interface documentation: Refer to the [Anchor API documentation]( to ensure you understand how to access block hashes using the fetch method.

Compatibility Issues: A Potential Cause

Another possible reason for this error is a compatibility issue between your testing library and Anchor. The fetch method may not work as expected due to differences in implementation or API usage.

• Try an alternative RPC interface

  : If you’re experiencing issues with the fetch method, try using another RPC interface that is compatible with the version of Anchor you’re using.

• Check your testing library’s documentation: Refer to the documentation for your preferred testing library (e.g., Web3.py or solana-api) to see if there are any known compatibility issues.

Example Code

To get a recent block hash, you can use the following code snippet:

import anchor from 'anchor';


const connection = await anchor.connect();

console.log(connection.getLatestBlockhash());

Note that this requires the anchor library and has been updated to work with Solana’s latest RPC interface.

Conclusion

The error “TypeError: fetch failed in Anchor test” can be resolved by updating Anchor to the latest version, checking the RPC interface documentation, or attempting alternative RPC interfaces. Additionally, compatibility issues between your testing library and Anchor may need to be addressed.

By following these steps and experimenting with different approaches, you should be able to successfully obtain recent block hashes on Solana using Anchor.