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Class: AWS.QLDBSession

Inherits:

AWS.Service

• Object
• AWS.Service
• AWS.QLDBSession

Identifier:

qldbsession

API Version:

2019-07-11

Defined in:

(unknown)

Overview

Constructs a service interface object. Each API operation is exposed as a function on service.

Service Description

The transactional data APIs for Amazon QLDB

Sending a Request Using QLDBSession

var qldbsession = new AWS.QLDBSession();
qldbsession.sendCommand(params, function (err, data) {
  if (err) console.log(err, err.stack); // an error occurred
  else     console.log(data);           // successful response
});

Locking the API Version

In order to ensure that the QLDBSession object uses this specific API, you can construct the object by passing the apiVersion option to the constructor:

var qldbsession = new AWS.QLDBSession({apiVersion: '2019-07-11'});

You can also set the API version globally in AWS.config.apiVersions using the qldbsession service identifier:

AWS.config.apiVersions = {
  qldbsession: '2019-07-11',
  // other service API versions
};

var qldbsession = new AWS.QLDBSession();

Version:

• 2019-07-11

Constructor Summary

• new AWS.QLDBSession(options = {}) ⇒ Object constructor

  Constructs a service object.

Property Summary

• endpoint ⇒ AWS.Endpoint readwrite

  An Endpoint object representing the endpoint URL for service requests.

Properties inherited from AWS.Service

apiVersions

Method Summary

• sendCommand(params = {}, callback) ⇒ AWS.Request

  Sends a command to an Amazon QLDB ledger.

Methods inherited from AWS.Service

makeRequest, makeUnauthenticatedRequest, waitFor, setupRequestListeners, defineService

Constructor Details

new AWS.QLDBSession(options = {}) ⇒ Object

Constructs a service object. This object has one method for each API operation.

Examples:

Constructing a QLDBSession object

var qldbsession = new AWS.QLDBSession({apiVersion: '2019-07-11'});

Options Hash (options):

• params (map) —

  An optional map of parameters to bind to every request sent by this service object. For more information on bound parameters, see "Working with Services" in the Getting Started Guide.

• endpoint (String) —

  The endpoint URI to send requests to. The default endpoint is built from the configured region. The endpoint should be a string like 'https://{service}.{region}.amazonaws.com'.

• accessKeyId (String) —

  your AWS access key ID.

• secretAccessKey (String) —

  your AWS secret access key.

• sessionToken (AWS.Credentials) —

  the optional AWS session token to sign requests with.

• credentials (AWS.Credentials) —

  the AWS credentials to sign requests with. You can either specify this object, or specify the accessKeyId and secretAccessKey options directly.

• credentialProvider (AWS.CredentialProviderChain) —

  the provider chain used to resolve credentials if no static credentials property is set.

• region (String) —

  the region to send service requests to. See AWS.QLDBSession.region for more information.

• maxRetries (Integer) —

  the maximum amount of retries to attempt with a request. See AWS.QLDBSession.maxRetries for more information.

• maxRedirects (Integer) —

  the maximum amount of redirects to follow with a request. See AWS.QLDBSession.maxRedirects for more information.

• sslEnabled (Boolean) —

  whether to enable SSL for requests.

• paramValidation (Boolean|map) —

  whether input parameters should be validated against the operation description before sending the request. Defaults to true. Pass a map to enable any of the following specific validation features:

  • min [Boolean] — Validates that a value meets the min constraint. This is enabled by default when paramValidation is set to true.
  • max [Boolean] — Validates that a value meets the max constraint.
  • pattern [Boolean] — Validates that a string value matches a regular expression.
  • enum [Boolean] — Validates that a string value matches one of the allowable enum values.
• computeChecksums (Boolean) —

  whether to compute checksums for payload bodies when the service accepts it (currently supported in S3 only)

• convertResponseTypes (Boolean) —

  whether types are converted when parsing response data. Currently only supported for JSON based services. Turning this off may improve performance on large response payloads. Defaults to true.

• correctClockSkew (Boolean) —

  whether to apply a clock skew correction and retry requests that fail because of an skewed client clock. Defaults to false.

• s3ForcePathStyle (Boolean) —

  whether to force path style URLs for S3 objects.

• s3BucketEndpoint (Boolean) —

  whether the provided endpoint addresses an individual bucket (false if it addresses the root API endpoint). Note that setting this configuration option requires an endpoint to be provided explicitly to the service constructor.

• s3DisableBodySigning (Boolean) —

  whether S3 body signing should be disabled when using signature version v4. Body signing can only be disabled when using https. Defaults to true.

• retryDelayOptions (map) —

  A set of options to configure the retry delay on retryable errors. Currently supported options are:

  • base [Integer] — The base number of milliseconds to use in the exponential backoff for operation retries. Defaults to 100 ms for all services except DynamoDB, where it defaults to 50ms.
  • customBackoff [function] — A custom function that accepts a retry count and error and returns the amount of time to delay in milliseconds. If the result is a non-zero negative value, no further retry attempts will be made. The base option will be ignored if this option is supplied.
• httpOptions (map) —

  A set of options to pass to the low-level HTTP request. Currently supported options are:

  • proxy [String] — the URL to proxy requests through
  • agent [http.Agent, https.Agent] — the Agent object to perform HTTP requests with. Used for connection pooling. Defaults to the global agent (http.globalAgent) for non-SSL connections. Note that for SSL connections, a special Agent object is used in order to enable peer certificate verification. This feature is only available in the Node.js environment.
  • connectTimeout [Integer] — Sets the socket to timeout after failing to establish a connection with the server after connectTimeout milliseconds. This timeout has no effect once a socket connection has been established.
  • timeout [Integer] — Sets the socket to timeout after timeout milliseconds of inactivity on the socket. Defaults to two minutes (120000).
  • xhrAsync [Boolean] — Whether the SDK will send asynchronous HTTP requests. Used in the browser environment only. Set to false to send requests synchronously. Defaults to true (async on).
  • xhrWithCredentials [Boolean] — Sets the "withCredentials" property of an XMLHttpRequest object. Used in the browser environment only. Defaults to false.
• apiVersion (String, Date) —

  a String in YYYY-MM-DD format (or a date) that represents the latest possible API version that can be used in all services (unless overridden by apiVersions). Specify 'latest' to use the latest possible version.

• apiVersions (map<String, String|Date>) —

  a map of service identifiers (the lowercase service class name) with the API version to use when instantiating a service. Specify 'latest' for each individual that can use the latest available version.

• logger (#write, #log) —

  an object that responds to .write() (like a stream) or .log() (like the console object) in order to log information about requests

• systemClockOffset (Number) —

  an offset value in milliseconds to apply to all signing times. Use this to compensate for clock skew when your system may be out of sync with the service time. Note that this configuration option can only be applied to the global AWS.config object and cannot be overridden in service-specific configuration. Defaults to 0 milliseconds.

• signatureVersion (String) —

  the signature version to sign requests with (overriding the API configuration). Possible values are: 'v2', 'v3', 'v4'.

• signatureCache (Boolean) —

  whether the signature to sign requests with (overriding the API configuration) is cached. Only applies to the signature version 'v4'. Defaults to true.

• dynamoDbCrc32 (Boolean) —

  whether to validate the CRC32 checksum of HTTP response bodies returned by DynamoDB. Default: true.

• useAccelerateEndpoint (Boolean) —

  Whether to use the S3 Transfer Acceleration endpoint with the S3 service. Default: false.

• clientSideMonitoring (Boolean) —

  whether to collect and publish this client's performance metrics of all its API requests.

• endpointDiscoveryEnabled (Boolean) —

  whether to enable endpoint discovery for operations that allow optionally using an endpoint returned by the service. Defaults to 'false'

• endpointCacheSize (Number) —

  the size of the global cache storing endpoints from endpoint discovery operations. Once endpoint cache is created, updating this setting cannot change existing cache size. Defaults to 1000

• hostPrefixEnabled (Boolean) —

  whether to marshal request parameters to the prefix of hostname. Defaults to true.

• stsRegionalEndpoints ('legacy'|'regional') —

  whether to send sts request to global endpoints or regional endpoints. Defaults to 'legacy'.

Property Details

endpoint ⇒ AWS.Endpoint (readwrite)

Returns an Endpoint object representing the endpoint URL for service requests.

Returns:

• (AWS.Endpoint) —

  an Endpoint object representing the endpoint URL for service requests.

Method Details

sendCommand(params = {}, callback) ⇒ AWS.Request

Sends a command to an Amazon QLDB ledger.

Service Reference:

• SendCommand

Examples:

Calling the sendCommand operation

var params = {
  AbortTransaction: {
  },
  CommitTransaction: {
    CommitDigest: Buffer.from('...') || 'STRING_VALUE' /* Strings will be Base-64 encoded on your behalf */, /* required */
    TransactionId: 'STRING_VALUE' /* required */
  },
  EndSession: {
  },
  ExecuteStatement: {
    Statement: 'STRING_VALUE', /* required */
    TransactionId: 'STRING_VALUE', /* required */
    Parameters: [
      {
        IonBinary: Buffer.from('...') || 'STRING_VALUE' /* Strings will be Base-64 encoded on your behalf */,
        IonText: 'STRING_VALUE'
      },
      /* more items */
    ]
  },
  FetchPage: {
    NextPageToken: 'STRING_VALUE', /* required */
    TransactionId: 'STRING_VALUE' /* required */
  },
  SessionToken: 'STRING_VALUE',
  StartSession: {
    LedgerName: 'STRING_VALUE' /* required */
  },
  StartTransaction: {
  }
};
qldbsession.sendCommand(params, function(err, data) {
  if (err) console.log(err, err.stack); // an error occurred
  else     console.log(data);           // successful response
});

Parameters:

• params (Object) (defaults to: {}) —
  • SessionToken — (String)

    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.

  • StartSession — (map)

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

    • LedgerName — required — (String)

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

  • StartTransaction — (map)

    Command to start a new transaction.

  • EndSession — (map)

    Command to end the current session.

  • CommitTransaction — (map)

    Command to commit the specified transaction.

    • TransactionId — required — (String)

      Specifies the transaction id of the transaction to commit.

    • CommitDigest — required — (Buffer, Typed Array, Blob, String)

      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.

  • AbortTransaction — (map)

    Command to abort the current transaction.

  • ExecuteStatement — (map)

    Command to execute a statement in the specified transaction.

    • TransactionId — required — (String)

      Specifies the transaction id of the request.

    • Statement — required — (String)

      Specifies the statement of the request.

    • Parameters — (Array<map>)

      Specifies the parameters for the parameterized statement in the request.

      • IonBinary — (Buffer, Typed Array, Blob, String)

        An Amazon Ion binary value contained in a ValueHolder structure.

      • IonText — (String)

        An Amazon Ion plaintext value contained in a ValueHolder structure.

  • FetchPage — (map)

    Command to fetch a page.

    • TransactionId — required — (String)

      Specifies the transaction id of the page to be fetched.

    • NextPageToken — required — (String)

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

Callback (callback):

• function(err, data) { ... }

  Called when a response from the service is returned. If a callback is not supplied, you must call AWS.Request.send() on the returned request object to initiate the request.

  Context (this):

  • (AWS.Response) —

    the response object containing error, data properties, and the original request object.

  Parameters:

  • err (Error) —

    the error object returned from the request. Set to null if the request is successful.

  • data (Object) —

    the de-serialized data returned from the request. Set to null if a request error occurs. The data object has the following properties:

    • StartSession — (map)

      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 — (map)

      Contains the details of the started transaction.

      • TransactionId — (String)

        The transaction id of the started transaction.

    • EndSession — (map)

      Contains the details of the ended session.

    • CommitTransaction — (map)

      Contains the details of the committed transaction.

      • TransactionId — (String)

        The transaction id of the committed transaction.

      • CommitDigest — (Buffer, Typed Array, Blob, String)

        The commit digest of the committed transaction.

    • AbortTransaction — (map)

      Contains the details of the aborted transaction.

    • ExecuteStatement — (map)

      Contains the details of the executed statement.

      • FirstPage — (map)

        Contains the details of the first fetched page.

        • Values — (Array<map>)

          A structure that contains values in multiple encoding formats.

          • IonBinary — (Buffer, Typed Array, Blob, String)

            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 — (map)

      Contains the details of the fetched page.

      • Page — (map)

        Contains details of the fetched page.

        • Values — (Array<map>)

          A structure that contains values in multiple encoding formats.

          • IonBinary — (Buffer, Typed Array, Blob, String)

            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.

Returns:

• (AWS.Request) —

  a handle to the operation request for subsequent event callback registration.