get_block

get_block(**kwargs)

Returns a block object at a specified address in a journal. Also returns a proof of the specified block for verification if DigestTipAddress is provided.

For information about the data contents in a block, see Journal contents in the Amazon QLDB Developer Guide .

If the specified ledger doesn't exist or is in DELETING status, then throws ResourceNotFoundException .

If the specified ledger is in CREATING status, then throws ResourcePreconditionNotMetException .

If no block exists with the specified address, then throws InvalidParameterException .

See also: AWS API Documentation

Request Syntax

response = client.get_block(
    Name='string',
    BlockAddress={
        'IonText': 'string'
    },
    DigestTipAddress={
        'IonText': 'string'
    }
)

Parameters

• Name (string) --

  [REQUIRED]

  The name of the ledger.

• BlockAddress (dict) --

  [REQUIRED]

  The location of the block that you want to request. An address is an Amazon Ion structure that has two fields: strandId and sequenceNo .

  For example: {strandId:"BlFTjlSXze9BIh1KOszcE3",sequenceNo:14} .

  • IonText (string) --

    An Amazon Ion plaintext value contained in a ValueHolder structure.

• DigestTipAddress (dict) --

  The latest block location covered by the digest for which to request a proof. An address is an Amazon Ion structure that has two fields: strandId and sequenceNo .

  For example: {strandId:"BlFTjlSXze9BIh1KOszcE3",sequenceNo:49} .

  • IonText (string) --

    An Amazon Ion plaintext value contained in a ValueHolder structure.

Return type

dict

Returns

Response Syntax

{
    'Block': {
        'IonText': 'string'
    },
    'Proof': {
        'IonText': 'string'
    }
}

Response Structure

• (dict) --

  • Block (dict) --

    The block data object in Amazon Ion format.

    • IonText (string) --

      An Amazon Ion plaintext value contained in a ValueHolder structure.

  • Proof (dict) --

    The proof object in Amazon Ion format returned by a GetBlock request. A proof contains the list of hash values required to recalculate the specified digest using a Merkle tree, starting with the specified block.

    • IonText (string) --

      An Amazon Ion plaintext value contained in a ValueHolder structure.

Exceptions

• QLDB.Client.exceptions.InvalidParameterException
• QLDB.Client.exceptions.ResourceNotFoundException
• QLDB.Client.exceptions.ResourcePreconditionNotMetException