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

Connect to RabbitMQ Data as a JDBC Data Source

To connect to RabbitMQ 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.

  About RabbitMQ Management HTTP API

  RabbitMQ is an open-source message broker that supports multiple messaging protocols. The RabbitMQ Management HTTP API provides HTTP-based access to management and monitoring data for a RabbitMQ server. The API exposes information about virtual hosts, exchanges, queues, bindings, connections, channels, consumers, users, permissions, policies, and cluster-wide statistics.

  The Management plugin must be enabled on the RabbitMQ server for the HTTP API to be available. By default, the management interface listens on port 15672.

  Using Basic Authentication

  RabbitMQ Management HTTP API uses HTTP Basic authentication. You must supply the username and password of a RabbitMQ management user.

  To enable access to the management API:

  1. Ensure the RabbitMQ Management plugin is enabled on your server (rabbitmq-plugins enable rabbitmq_management).
  2. Use an existing management user or create one with the appropriate management tag (management, policymaker, monitoring, or administrator).
  3. Note the full base URL of your RabbitMQ Management HTTP API (e.g., http://localhost:15672).

  After configuring your RabbitMQ server, set the following connection properties to connect:

  • AuthScheme: Set this to Basic.
  • URL: Set this to the base URL of your RabbitMQ Management HTTP API (e.g., http://localhost:15672).
  • User: Set this to your RabbitMQ management username (e.g., guest).
  • Password: Set this to your RabbitMQ management password.

  Example connection string:

  Profile=C:\profiles\RabbitMQ.apip;AuthScheme=Basic;URL=http://localhost:15672;User=guest;Password=guest;
  

  Available Tables

  The RabbitMQ profile provides access to the following tables:

  • Overview - Cluster-wide statistics and information about the RabbitMQ node
  • Nodes - Information about individual nodes in the RabbitMQ cluster
  • NodeMemory - Detailed memory usage breakdown for a specific cluster node
  • Connections - List of all open AMQP connections to the broker
  • Channels - List of all open AMQP channels across all connections
  • Consumers - List of all consumers registered across all queues
  • Exchanges - List of exchanges declared across all virtual hosts
  • Queues - List of queues declared across all virtual hosts
  • Bindings - List of all bindings between exchanges and queues
  • VirtualHosts - List of virtual hosts configured on the broker
  • VhostPermissions - User permissions within a specific virtual host
  • Users - List of all RabbitMQ users
  • Permissions - Permission records for all users across all virtual hosts
  • TopicPermissions - Topic-level permission records for all users
  • Policies - List of policies applied to queues and exchanges in virtual hosts
  • OperatorPolicies - List of operator policies applied to queues in virtual hosts
  • Parameters - List of component parameters (e.g., federation, shovel) per virtual host
  • GlobalParameters - List of global parameters that apply across all virtual hosts
  • VhostLimits - Resource limits configured for specific virtual hosts
  • UserLimits - Resource limits configured for specific users
  • FeatureFlags - List of feature flags and their enabled/disabled state on the node
  • DeprecatedFeatures - List of deprecated features and their usage state
  • AuthAttempts - Authentication attempt statistics for the node
  • ClusterName - The name of the RabbitMQ cluster
  • WhoAmI - Information about the currently authenticated management user
  • ExchangeBindingsSource - Bindings for which a specific exchange is the source
  • ExchangeBindingsDestination - Bindings for which a specific exchange is the destination
  • QueueBindings - Bindings for a specific queue within a virtual host

  Built-in Connection String Designer

  For assistance in constructing the JDBC URL, use the connection string designer built into the RabbitMQ 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\\RabbitMQ.apip;AuthScheme=Basic;URL=http://localhost:15672;User=guest;Password=guest;
  

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 RabbitMQ Data as a PostgreSQL Database

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

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

   CREATE EXTENSION jdbc2_fdw;
   

3. Create a server object for RabbitMQ:

   CREATE SERVER API 
   FOREIGN DATA WRAPPER jdbc2_fdw OPTIONS (
   drivername 'cdata.jdbc.api.APIDriver',
   url 'jdbc:api:Profile=C:\profiles\\RabbitMQ.apip;AuthScheme=Basic;URL=http://localhost:15672;User=guest;Password=guest;',
   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 authattempts (
   authattempts_id text,
   authattempts_ text,
   authattempts_ numeric) 
   SERVER API OPTIONS (
   table_name 'authattempts');
   

postgres=# SELECT * FROM authattempts;