Using AWS Lambda with IBM App Connect Enterprise

AWS Lambda is an event-driven, serverless computing platform offered by Amazon Web Services (AWS). By using AWS Lambda, you can run code for applications or backend services without provisioning or managing servers.

1. In the IBM App Connect Enterprise Toolkit, create a flow that contains an AWS Lambda Request node.
2. Select the AWS Lambda Request node in the flow to show the node properties in the editor.
3. On the Basic tab, click Launch Connector Discovery.
   A panel is displayed in which you specify the name of the policy project and vault details to be used during connector discovery.
4. Specify the details of the policy project and vault to be used during connector discovery:
   1. In the Policy Project field, specify the policy project that is used to store the policies that are created during connector discovery.
      Alternatively, you can create a new policy project by clicking New and then specifying the name of the new policy project. Then click Finish.
   2. Specify the vault to be used during connector discovery. By default, credentials that are used during connector discovery are stored in an external directory vault, which is an App Connect Enterprise vault that can be used by any integration server. Alternatively, you can store the credentials in an integration server vault, which is created in the integration server's work directory and can be used only by that specific integration server.
      To specify the vault to be used for storing the credentials, complete the steps in the Using the Connector Discovery wizard section of one of the following topics:

      • Configuring an external directory vault
      • Configuring an integration server vault
   3. In the Vault key field, enter the vault key that is used to access the credentials stored in the vault. The vault key must be at least 8 characters in length.
   4. Optional: By default, the specified vault location and vault key are saved as preferences in the Toolkit so that the values are preset when you launch Connector Discovery. If you do not want the preferences to be saved, deselect Save in vault preferences.
5. Click Launch Discovery to start the Connector Discovery wizard for the AWS Lambda connector.
   The Connector Discovery window is displayed. If existing AWS Lambda connections (accounts) are available, a list of those connections is displayed. If there are no existing connections, the status of the AWS Lambda connector is shown as Not connected.
   • If one or more AWS Lambda connections (accounts) are available, complete the following steps:
     1. Select the connection (account) that you want to use by clicking it.
     2. Click the required object type and then select the action that you want to perform on the object. For example, to retrieve functions from AWS Lambda, click Functions and then Retrieve functions.
   • If there are no existing connections (accounts), complete the following steps:
     1. Click the required object type and then select the action that you want to perform on that object. For example, to retrieve functions from AWS Lambda, click Functions and then Retrieve functions.
     2. Click Connect to create a new connection. A window is displayed in which you enter the details of your account.
     3. Enter the following details:
        1. In the Secret access key field, enter the secret access key of your AWS Lambda account. Get the secret access key from the Security Credentials page in the AWS Management Console.
        2. In the Access key ID field, enter the access key ID of your AWS Lambda account. Get the access key ID from the Security Credentials page in the AWS Management Console.
        3. In the Region field, enter the region of your AWS Lambda instance, for example, us-east-1.
        4. Proxy name: If necessary, enter the name of the proxy that you want IBM App Connect Enterprise to use to pass the connector calls.
     4. Click Connect.

     For more information about connecting to AWS Lambda, see How to use IBM App Connect with AWS Lambda in the IBM App Connect Enterprise as a Service documentation.

6. Set the required connector properties in the wizard.
   You can add conditions for the retrieval of the functions (such as specifying a particular Function version), and you can set properties that specify the maximum number of functions to retrieve and the action to be taken if that limit is exceeded.
7. When you have finished specifying the properties in the Connector Discovery wizard, click Save.

   The credential that is used for connecting to AWS Lambda is stored in the vault, and the other connection details, including details of the specified function version (if any), are saved in the AWS Lambda policy. The values of the properties that you set in the wizard are returned to the AWS Lambda Request node in the IBM App Connect Enterprise Toolkit.

8. When you finish discovery and save the property values, exit the Connector Discovery wizard by clicking the X in the upper-right corner of the window or by pressing Alt+F4.
9. Return to editing the AWS Lambda Request node in the IBM App Connect Enterprise Toolkit.
   The connector properties that were set in the Connector Discovery wizard (in step 6) are now visible on the AWS Lambda Request node. The Basic tab shows the values of the Action and Object properties that you set in the wizard. For example, if you selected Functions > Retrieve functions in the wizard, the following properties are visible on the Basic tab of the node:

   • Action - RETRIEVEALL
   • Object - function

   The values of the Action and Object properties are displayed in read-only format. If you want to change these values, you can do so by clicking Launch Connector Discovery again and setting new values in the Connector Discovery wizard.

   The Schema base name property specifies the base name of the schema files that describe the format of the request and response messages that are sent and received from theAWS Lambda connector. The schema base name is set automatically the first time that you run discovery for the node, and it is based on the AWS Lambda current flow name and node name. If you set this property manually before you run discovery for the first time, the value that you set is used. If you rename the schemas after discovery, you must edit this property so that it matches the schema base name that is used by the renamed schemas in the project. If you change this property after discovery, you must either rename the schema names to match or run discovery again.

   Depending on the action that was selected during discovery, the Connector Discovery wizard generates either a request schema and a response schema, or a response schema only. A request schema is generated only if the selected action and object require a request message. The generated request schema is used for validation of the request message. If the action was RETRIEVE or DELETE, only the response schema is returned by the connector.

   The generated schema files are added to the project and you can use it with a Mapping node for transforming input or output data. The full filename of the schema is derived from the schema base name (such as gen/MyMessageFlow.AWSlambda_Request), suffixed with either response.schema.json or request.schema.json. You can open the schema by clicking Open request schema or Open response schema.

10. Check that the property settings on the AWS Lambda Request node are correct and then save the message flow.
11. On the Connection tab of the AWS Lambda Request node, the Policy property shows the name of the policy that contains the details of the security identity to be used for the connection. The policy has a type of AWS Lambda.
    For more information, see AWS Lambda policy.
12. Optional: Set the Timeout property on the Connection tab to specify the time (in seconds) that the node waits for AWS Lambda to process the operation.
13. The Filter tab of the AWS Lambda Request node contains properties that control the way in which the message flow selects data. The initial values of these properties are taken from the property values that were set for the AWS Lambda connector in the Connector Discovery wizard, including filter options properties and any conditions that were specified (as described in step 6). If you subsequently return to the Connector Discovery wizard and change the values of any properties (by adding new conditions, for example) those updates are reflected in the properties set on the node.

    The Filter Options properties control which objects are to be operated upon when the AWS Lambda Request node executes. The Filter Limit properties control the maximum number of items to be retrieved and the action to be taken if the limit is exceeded.

    You can modify the values by clicking Edit next to the value that you want to modify in the Filter Options section, and by changing the property values that have been set in the Filter Limit section.

    The property values can be either text values or ESQL or XPATH expressions that are resolved from the contents of the message that is passed to the AWS Lambda Request node as it executes.

14. On the Request tab, set the Data location property to specify the location in the incoming message tree that contains the object data to be created in AWS Lambda. This data forms the request that is sent from the AWS Lambda Request node to the AWS Lambda system.
15. On the Result tab, set the Output data location property to specify the location in the output message tree that contains the data of the record that is created in AWS Lambda.
16. By default, request messages are validated against the request schema that was generated during connector discovery. You can turn off request validation or change the validation settings by using the Validation properties of the AWS Lambda Request node.
17. Save the message flow.