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

Connect to Coinbase Data as a JDBC Data Source

To connect to Coinbase 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.

  Start by setting the Profile connection property to the location of the Coinbase Profile on disk (e.g. C:\profiles\Coinbase.apip). Next, set the ProfileSettings connection property to the connection string for Coinbase (see below).

  Coinbase API Profile Settings

  Coinbase uses OAuth-based authentication.

  First you need to register an OAuth app with Coinbase. This is done from your account under 'Settings' > 'API Access' > 'New OAuth2 Application'.

  After setting the following connection properties, you are ready to connect:

  • AuthScheme: Set this to OAuth.
  • InitiateOAuth: Set this to GETANDREFRESH. You can use InitiateOAuth to manage the process to obtain the OAuthAccessToken.
  • OAuthClientId: Set this to the ClientID that is specified in you app settings.
  • OAuthClientSecret: Set this to the ClientSecret that is specified in you app settings.
  • CallbackURL: Set this to the Redirect URI you specified in your app settings.

  Built-in Connection String Designer

  For assistance in constructing the JDBC URL, use the connection string designer built into the Coinbase 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.

  👁 Using the built-in connection string designer to generate a JDBC URL (Salesforce is shown.)
  

  A typical JDBC URL is below:

  jdbc:api:Profile=C:\profiles\Coinbase.apip;Authscheme=OAuth;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 Coinbase Data as a PostgreSQL Database

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

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

   CREATE EXTENSION jdbc2_fdw;
   

3. Create a server object for Coinbase:

   CREATE SERVER API 
   FOREIGN DATA WRAPPER jdbc2_fdw OPTIONS (
   drivername 'cdata.jdbc.api.APIDriver',
   url 'jdbc:api:Profile=C:\profiles\Coinbase.apip;Authscheme=OAuth;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 deposits (
   deposits_id text,
   deposits_Id text,
   deposits_Amount numeric) 
   SERVER API OPTIONS (
   table_name 'deposits');
   

You can now execute SELECT commands to Coinbase:

postgres=# SELECT * FROM deposits;