Build Google Cloud Storage-Connected Apps in Choreo

The Choreo platform from WS02 is a versatile platform designed for low-code and cloud-native engineering. Developers, even those without advanced coding skills, can leverage Choreo's user-friendly low-code environment to simplify application development. When combined with CData Connect AI, users gain immediate cloud-to-cloud access to Google Cloud Storage data for applications. This article details the process of connecting to Google Cloud Storage using Connect AI and building an application with real-time access to Google Cloud Storage data within Choreo.

CData Connect AI delivers a pure cloud-to-cloud interface for Google Cloud Storage, enabling you to construct applications within Choreo that utilize live Google Cloud Storage data data, all without the need for data replication to a natively supported database. With its built-in optimized data processing capabilities, CData Connect AI efficiently directs all supported SQL operations, including filters and JOINs, directly to Google Cloud Storage, capitalizing on server-side processing to swiftly provide the requested Google Cloud Storage data.

Configure Google Cloud Storage Connectivity for Choreo

Connectivity to Google Cloud Storage from Choreo is made possible through CData Connect AI. To work with Google Cloud Storage data from Choreo, we start by creating and configuring a Google Cloud Storage connection.

1. Log into Connect AI, click Sources, and then click Add Connection

2. Select "Google Cloud Storage" from the Add Connection panel

3. Enter the necessary authentication properties to connect to Google Cloud Storage.

   Authenticate with a User Account

   You can connect without setting any connection properties for your user credentials. After setting InitiateOAuth to GETANDREFRESH, you are ready to connect.

   When you connect, the Google Cloud Storage OAuth endpoint opens in your default browser. Log in and grant permissions, then the OAuth process completes

   Authenticate with a Service Account

   Service accounts have silent authentication, without user authentication in the browser. You can also use a service account to delegate enterprise-wide access scopes.

   You need to create an OAuth application in this flow. See the Help documentation for more information. After setting the following connection properties, you are ready to connect:

   • InitiateOAuth: Set this to GETANDREFRESH.
   • OAuthJWTCertType: Set this to "PFXFILE".
   • OAuthJWTCert: Set this to the path to the .p12 file you generated.
   • OAuthJWTCertPassword: Set this to the password of the .p12 file.
   • OAuthJWTCertSubject: Set this to "*" to pick the first certificate in the certificate store.
   • OAuthJWTIssuer: In the service accounts section, click Manage Service Accounts and set this field to the email address displayed in the service account Id field.
   • OAuthJWTSubject: Set this to your enterprise Id if your subject type is set to "enterprise" or your app user Id if your subject type is set to "user".
   • ProjectId: Set this to the Id of the project you want to connect to.

   The OAuth flow for a service account then completes.

   
4. Click Save & Test
5. Navigate to the Permissions tab in the Add Google Cloud Storage Connection page and update the User-based permissions.

Add a Personal Access Token

When connecting to Connect AI through the REST API, the OData API, or the Virtual SQL Server, a Personal Access Token (PAT) is used to authenticate the connection to Connect AI. It is best practice to create a separate PAT for each service to maintain granularity of access.

1. Click on the Gear icon () at the top right of the Connect AI app to open the settings page.
2. On the Settings page, go to the Access Tokens section and click Create PAT.
3. Give the PAT a name and click Create.
4. The personal access token is only visible at creation, so be sure to copy it and store it securely for future use.

With the connection configured and a PAT generated, you are ready to connect to Google Cloud Storage data from Choreo.

Connect to Google Cloud Storage from Choreo

The steps below outline connecting to CData Connect AI from Choreo to create a new application with access to live Google Cloud Storage data.

Creating a Construct

1. Sign in to the Choreo platform. Note: This article is from the perspective of an Anonymous user.
2. Select Components from the left sidebar and then click +Create. Next, choose Manual Trigger and then Start from scratch.
3. Give the manual trigger a Name and Description and click Create.
4. After the trigger is created, click on Edit Code.
5. The Ballerina Low-Code IDE is displayed. Choreo automatically generates a construct in the low-code diagram view. Delete this construct by highlighting it and clicking on the trashcan icon.
6. Click the + icon towards the top of the screen and select Main from the Add Constructs toolbar on the right. In the following Function Configuration form, click Save.

Adding the CData Connect AI Connector

1. Click the + icon between the Start and End ellipses and click Connector.

2. In the Connectors sidebar on the right, search for "CData". Click CData Connect to open the Connector settings pane.

3. In the Connector settings pane, enter the configuration settings:
   • Enter an Endpoint Name for your use. In this example, we use "connectEndpoint".
   • In the User field, enter the email address of the CData Connect AI user, wrapped in quotation marks (for example, "[email protected]").
   • In the Password field, enter the PAT you generated earlier, wrapped in quotation marks (for example, "SampleToken").

4. After clicking Save, the low-code editor appears with the CData Connect AI logo.

Adding a Query Action

1. Click the + icon between the new and end shapes, select Action, and then select our existing connector endpoint.

2. Select query for the connector Operation. There is now an Action pane on the right.

3. Enter a SQL query to retrieve Google Cloud Storage data as the sqlQuery parameter for the query. For example:

   			SELECT * FROM GoogleCloudStorage1.GoogleCloudStorage.Buckets LIMIT 10
   		

   • When writing the query, be sure to specify the Connection Name as the catalog and Data Source Name as the schema. For example, GoogleCloudStorage1.GoogleCloudStorage.
   • These parameters appear on the Connections page of your CData Connect AI dashboard.

Iterating over Google Cloud Storage Data

1. Click the Show Source icon in the top right of the code editor.
2. Add an import statment to import the ballerina/io library:

   		
   		import ballerina/io;
   	

3. Next, add a from statement after the query action to iterate through the results of the SQL query:

		
		check from record{} result in resultStream
		do {
			io:println("Full Buckets details: ", result);
		};
	

4. The code for the construct will now look similar to this:

			
			import ballerinax/cdata.connect;
			import ballerinax/cdata.connect.driver as _;
			import ballerina/io;

			public function main() returns error? {
				connect:Client connectEp = check new (user = "connect_cloud_username", password="connect_cloud_pat");

				stream<record {}, error=""?> resultStream =
				connectEp->query(sqlQuery = `SELECT * FROM GoogleCloudStorage1.GoogleCloudStorage.Buckets LIMIT 10`);

				check from record{} result in resultStream
				do {
					io:println("Full Buckets details: ", result);
				};
			}
		

5. Click Save to save the action. The diagram should now look similar to this:

Deploying the Program

Once you have added all of your desired actions to your program, follow these steps:

1. Commit and push your final source code in the web editor and sync those changes with the Choreo platform.
2. Click Deploy in the left navigation bar of the Choreo Console.
3. Under Build Area, click Configure & Deploy to deploy your program.
4. When prompted, enter the same CData Connect AI username and password that you used earlier and click Deploy.

You have now created an application with access to live Google Cloud Storage data in Choreo.

Get CData Connect AI

For more information about using Choreo with CData Connect AI, see the CData Connect Ballerina Guide. To get live data access to hundreds of SaaS, Big Data, and NoSQL sources directly from your cloud applications, try CData Connect AI today!