archive_unstable_header

Parameters:

• hash: String containing the hexadecimal-encoded hash of the header to retreive.

Return value: If a block with that hash is found, a string containing the hexadecimal-encoded SCALE-codec encoding header of the block. If no block with that hash is found, null.

If the block was previously returned by archive_unstable_hashByHeight at a height inferior or equal to the current finalized block height (as indicated by archive_unstable_finalizedHeight), then calling this method multiple times is guaranteed to always return non-null and always the same result.

If the block was previously returned by archive_unstable_hashByHeight at a height strictly superior to the current finalized block height (as indicated by archive_unstable_finalizedHeight), then the block might "disappear" and calling this function might return null at any point.