Amazon QLDB Session

Sends a command to an Amazon QLDB ledger.

See also: AWS API Documentation

Request Syntax

client.send_command(
    SessionToken='string',
    StartSession={
        'LedgerName': 'string'
    },
    StartTransaction={}
    ,
    EndSession={}
    ,
    CommitTransaction={
        'TransactionId': 'string',
        'CommitDigest': b'bytes'
    },
    AbortTransaction={}
    ,
    ExecuteStatement={
        'TransactionId': 'string',
        'Statement': 'string',
        'Parameters': [
            {
                'IonBinary': b'bytes',
                'IonText': 'string'
            },
        ]
    },
    FetchPage={
        'TransactionId': 'string',
        'NextPageToken': 'string'
    }
)

type SessionToken:

string

param SessionToken:

Specifies the session token for the current command. A session token is constant throughout the life of the session.

To obtain a session token, run the StartSession command. This SessionToken is required for every subsequent command that is issued during the current session.

type StartSession:

dict

param StartSession:

Command to start a new session. A session token is obtained as part of the response.

• LedgerName (string) -- [REQUIRED]

  The name of the ledger to start a new session against.

type StartTransaction:

dict

param StartTransaction:

Command to start a new transaction.

type EndSession:

dict

param EndSession:

Command to end the current session.

type CommitTransaction:

dict

param CommitTransaction:

Command to commit the specified transaction.

• TransactionId (string) -- [REQUIRED]

  Specifies the transaction id of the transaction to commit.

• CommitDigest (bytes) -- [REQUIRED]

  Specifies the commit digest for the transaction to commit. For every active transaction, the commit digest must be passed. QLDB validates CommitDigest and rejects the commit with an error if the digest computed on the client does not match the digest computed by QLDB.

type AbortTransaction:

dict

param AbortTransaction:

Command to abort the current transaction.

type ExecuteStatement:

dict

param ExecuteStatement:

Command to execute a statement in the specified transaction.

• TransactionId (string) -- [REQUIRED]

  Specifies the transaction id of the request.

• Statement (string) -- [REQUIRED]

  Specifies the statement of the request.

• Parameters (list) --

  Specifies the parameters for the parameterized statement in the request.

  • (dict) --

    A structure that can contains values in multiple encoding formats.

    • IonBinary (bytes) --

      An Amazon Ion binary value contained in a ValueHolder structure.

    • IonText (string) --

      An Amazon Ion plaintext value contained in a ValueHolder structure.

type FetchPage:

dict

param FetchPage:

Command to fetch a page.

• TransactionId (string) -- [REQUIRED]

  Specifies the transaction id of the page to be fetched.

• NextPageToken (string) -- [REQUIRED]

  Specifies the next page token of the page to be fetched.

rtype:

dict

returns:

Response Syntax

{
    'StartSession': {
        'SessionToken': 'string'
    },
    'StartTransaction': {
        'TransactionId': 'string'
    },
    'EndSession': {},
    'CommitTransaction': {
        'TransactionId': 'string',
        'CommitDigest': b'bytes'
    },
    'AbortTransaction': {},
    'ExecuteStatement': {
        'FirstPage': {
            'Values': [
                {
                    'IonBinary': b'bytes',
                    'IonText': 'string'
                },
            ],
            'NextPageToken': 'string'
        }
    },
    'FetchPage': {
        'Page': {
            'Values': [
                {
                    'IonBinary': b'bytes',
                    'IonText': 'string'
                },
            ],
            'NextPageToken': 'string'
        }
    }
}

Response Structure

• (dict) --

  • StartSession (dict) --

    Contains the details of the started session that includes a session token. This SessionToken is required for every subsequent command that is issued during the current session.

    • SessionToken (string) --

      Session token of the started session. This SessionToken is required for every subsequent command that is issued during the current session.

  • StartTransaction (dict) --

    Contains the details of the started transaction.

    • TransactionId (string) --

      The transaction id of the started transaction.

  • EndSession (dict) --

    Contains the details of the ended session.

  • CommitTransaction (dict) --

    Contains the details of the committed transaction.

    • TransactionId (string) --

      The transaction id of the committed transaction.

    • CommitDigest (bytes) --

      The commit digest of the committed transaction.

  • AbortTransaction (dict) --

    Contains the details of the aborted transaction.

  • ExecuteStatement (dict) --

    Contains the details of the executed statement.

    • FirstPage (dict) --

      Contains the details of the first fetched page.

      • Values (list) --

        A structure that contains values in multiple encoding formats.

        • (dict) --

          A structure that can contains values in multiple encoding formats.

          • IonBinary (bytes) --

            An Amazon Ion binary value contained in a ValueHolder structure.

          • IonText (string) --

            An Amazon Ion plaintext value contained in a ValueHolder structure.

      • NextPageToken (string) --

        The token of the next page.

  • FetchPage (dict) --

    Contains the details of the fetched page.

    • Page (dict) --

      Contains details of the fetched page.

      • Values (list) --

        A structure that contains values in multiple encoding formats.

        • (dict) --

          A structure that can contains values in multiple encoding formats.

          • IonBinary (bytes) --

            An Amazon Ion binary value contained in a ValueHolder structure.

          • IonText (string) --

            An Amazon Ion plaintext value contained in a ValueHolder structure.

      • NextPageToken (string) --

        The token of the next page.