Configure the CData JDBC Driver for Google Cloud Storage in a Connection Pool in Tomcat

The CData JDBC Drivers support standard JDBC interfaces to integrate with Web applications running on the JVM. This article details how to connect to Google Cloud Storage data from a connection pool in Tomcat.

Connect to Google Cloud Storage Data through a Connection Pool in Tomcat

1. Copy the CData JAR and CData .lic file to $CATALINA_HOME/lib. The CData JAR is located in the lib subfolder of the installation directory.
2. Add a definition of the resource to the context. Specify the JDBC URL here.

   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.

   Built-in Connection String Designer

   For assistance in constructing the JDBC URL, use the connection string designer built into the Google Cloud Storage JDBC Driver. Either double-click the JAR file or execute the jar file from the command-line.

   java -jar cdata.jdbc.googlecloudstorage.jar

   Fill in the connection properties and copy the connection string to the clipboard.

   You can see the JDBC URL specified in the resource definition below.

   <Resource name="jdbc/googlecloudstorage" auth="Container" type="javax.sql.DataSource" driverClassName="cdata.jdbc.googlecloudstorage.GoogleCloudStorageDriver" factory="org.apache.tomcat.jdbc.pool.DataSourceFactory" url="jdbc:googlecloudstorage:ProjectId='project1';InitiateOAuth=GETANDREFRESH" maxActive="20" maxIdle="10" maxWait="-1" />

   To allow a single application to access Google Cloud Storage data, add the code above to the context.xml in the application's META-INF directory.

   For a shared resource configuration, add the code above to the context.xml located in $CATALINA_BASE/conf. A shared resource configuration provides connectivity to Google Cloud Storage for all applications.

3. Add a reference to the resource to the web.xml for the application. Google Cloud Storage data JSP jdbc/GoogleCloudStorage javax.sql.DataSource Container
4. Initialize connections from the connection pool: Context initContext = new InitialContext(); Context envContext = (Context)initContext.lookup("java:/comp/env"); DataSource ds = (DataSource)envContext.lookup("jdbc/GoogleCloudStorage"); Connection conn = ds.getConnection();

More Tomcat Integration

The steps above show how to connect to Google Cloud Storage data in a simple connection pooling scenario. For more use cases and information, see the JNDI Datasource How-To in the Tomcat documentation.