chainHead_v1_unpin

Parameters:

  • followSubscription: An opaque string that was returned by chainHead_v1_follow.
  • hashOrHashes: String or array of unique strings containing the hexadecimal-encoded hash of the header of the block to unpin.

Return value: null

See explanations in the documentation of chainHead_v1_follow.

On-going calls to chainHead_v1_body, chainHead_v1_call and chainHead_v1_storage against this block will still finish normally.

Has no effect if the followSubscription is invalid or stale.

If this function returns an error, then no block has been unpinned. An JSON-RPC server implementation is expected to start unpinning the blocks only after it has made sure that all the blocks could be unpinned.

Possible errors

  • A JSON-RPC error with error code -32801 is generated if the followSubscription is valid but at least one of the block hashes passed as parameter doesn't correspond to any block that has been reported by chainHead_v1_follow, or at least one of the block hashes has been unpinned.
  • A JSON-RPC error with error code -32804 is generated if the hashOrHashes parameter is an array and at least one of the block hashes is duplicated.
  • A JSON-RPC error with error code -32602 is generated if one of the parameters doesn't correspond to the expected type (similarly to a missing parameter or an invalid parameter type).
  • No error is generated if the followSubscription is invalid or stale. The call is simply ignored.