Build a PostgreSQL Interface for Google Translate Data using the CData JDBC Driver

There are a vast number of PostgreSQL clients available on the Internet. From standard Drivers to BI and Analytics tools, PostgreSQL is a popular interface for data access. Using our JDBC Drivers, you can now create PostgreSQL entry-points that you can connect to from any standard client.

To access Google Translate data as a PostgreSQL database, use the CData JDBC Driver for Google Translate and a JDBC foreign data wrapper (FDW). In this article, we compile the FDW, install it, and query Google Translate data from PostgreSQL Server.

Connect to Google Translate Data as a JDBC Data Source

To connect to Google Translate as a JDBC data source, you will need the following:

• Driver JAR path: The JAR is located in the lib subfolder of the installation directory.

• Driver class:

  cdata.jdbc.api.APIDriver
  

• JDBC URL: The URL must start with "jdbc:api:" and can include any of the connection properties in name-value pairs separated with semicolons.

  Authentication

  Google Cloud Translation API requires OAuth 2.0 authentication to ensure secure access to translation services, datasets, glossaries, and adaptive MT resources. This authentication method allows you to securely connect to your Google Cloud project and manage translation resources with proper authorization.

  OAuth 2.0 Setup and Configuration

  Step 1: Create Google Cloud Project and Enable API

  To set up OAuth authentication:

  1. Visit the Google Cloud Console
  2. Create a new project or select an existing project
  3. Note down your Project ID (required for all API calls)
  4. Navigate to "APIs & Services" > "Library"
  5. Search for and enable the "Cloud Translation API"
  6. Go to "APIs & Services" > "Credentials"
  7. Click "Create Credentials" and select "OAuth Client ID"
  8. Configure the OAuth consent screen if prompted
  9. Select "Desktop application" or "Web application" as appropriate
  10. Set the authorized redirect URI (CallbackURL)
  11. Copy the Client ID and Client Secret for use in your connection

  Required Connection Properties

  • AuthScheme: Set this to OAuth (required)
  • OAuthClientId: Client ID from Google Cloud Console (required)
  • OAuthClientSecret: Client secret from Google Cloud Console (required)
  • CallbackURL: Redirect URI specified in your OAuth application (required)
  • InitiateOAuth: Set to GETANDREFRESH for automatic token management (recommended)
  • ProjectId: Your Google Cloud project ID or project number (required for queries)

  Required OAuth Scopes

  The Google Cloud Translation API Profile requires the following OAuth scope:

  • https://www.googleapis.com/auth/cloud-translation - Full access to Cloud Translation API resources including translation, datasets, glossaries, and adaptive MT

  Built-in Connection String Designer

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

  java -jar cdata.jdbc.api.jar
  

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

  

  A typical JDBC URL is below:

  jdbc:api:Profile=C:\profiles\GoogleTranslate.apip;AuthScheme=OAuth;InitiateOAuth=GETANDREFRESH;OAuthClientId=your_client_id;OAuthClientSecret=your_client_secret;CallbackUrl=your_callback_url;
  

Build the JDBC Foreign Data Wrapper

The Foreign Data Wrapper can be installed as an extension to PostgreSQL, without recompiling PostgreSQL. The jdbc2_fdw extension is used as an example (downloadable here).

1. Add a symlink from the shared object for your version of the JRE to /usr/lib/libjvm.so. For example:

   ln -s /usr/lib/jvm/java-6-openjdk/jre/lib/amd64/server/libjvm.so /usr/lib/libjvm.so
   

2. Start the build:

   make install USE_PGXS=1
   

Query Google Translate Data as a PostgreSQL Database

After you have installed the extension, follow the steps below to start executing queries to Google Translate data:

1. Log into your database.
2. Load the extension for the database:

   CREATE EXTENSION jdbc2_fdw;
   

3. Create a server object for Google Translate:

   CREATE SERVER API 
   FOREIGN DATA WRAPPER jdbc2_fdw OPTIONS (
   drivername 'cdata.jdbc.api.APIDriver',
   url 'jdbc:api:Profile=C:\profiles\GoogleTranslate.apip;AuthScheme=OAuth;InitiateOAuth=GETANDREFRESH;OAuthClientId=your_client_id;OAuthClientSecret=your_client_secret;CallbackUrl=your_callback_url;',
   querytimeout '15',
   jarfile '/home/MyUser/CData/CData\ JDBC\ Driver\ for\ Salesforce MyDriverEdition/lib/cdata.jdbc.api.jar'); 
   

4. Create a user mapping for the username and password of a user known to the MySQL daemon.

   CREATE USER MAPPING for postgres SERVER API OPTIONS (
   username 'admin', 
   password 'test');
   

5. Create a foreign table in your local database:

   postgres=# CREATE FOREIGN TABLE supportedlanguages (
   supportedlanguages_id text,
   supportedlanguages_LanguageCode text,
   supportedlanguages_DisplayName numeric) 
   SERVER API OPTIONS (
   table_name 'supportedlanguages');
   

postgres=# SELECT * FROM supportedlanguages;