Provide OData Services of RabbitMQ Data from a WCF Application

The CData ADO.NET Provider for RabbitMQ enables you to rapidly develop service-oriented applications using the Windows Communication Foundation (WCF) framework, providing RabbitMQ data data to OData consumers. This article guides you through creating an entity data model for connectivity and a WCF Data Service to expose OData services. You can then consume the feed with various OData clients, such as Power Pivot or applications using the CData ADO.NET Provider for OData.

Create the OData Service

Follow the steps below to create a WCF service application that will provide connectivity to RabbitMQ data via OData.

1. Open Visual Studio and create a new project. Select the WCF Service Application template.
2. Delete the autogenerated IService.cs and Service1.svc.
3. Install Entity Framework 6:

   Use the Package Manager Console in Visual Studio to install the latest version of Entity Framework. Run the following command to download and install Entity Framework automatically:

   Install-Package EntityFramework

4. Register the Entity Framework provider:
   1. Add the following provider entry in the "providers" section of your App.config or Web.config file. This section should already exist if the Entity Framework installation was successful.

      <configuration>
      ...
      <entityFramework>
        <providers>
          ...
          <provider invariantName="System.Data.CData.API" type="System.Data.CData.API.APIProviderServices, System.Data.CData.API.Entities.EF6" />
        </providers>
      </entityFramework>
      </configuration>

   2. Add a reference to System.Data.CData.API.Entities.dll, located in lib/4.0 in the installation directory.
   3. Build the project to complete the setup for using EF6.
5. Click Project -> Add New Item -> ADO.NET Entity Data Model.
6. In the Entity Data Model wizard that is displayed, select the 'EF Designer from Database' option.
7. In the resulting Choose Your Connection dialog, click New Connection.

8. In the Connection properties dialog, select the CData RabbitMQ Data Source and enter the necessary credentials.

   A typical connection string is below:

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

   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
   
9. Select RabbitMQ tables and views that you want OData clients to access.
10. Click Project -> Add New Item -> WCF Data Service.

11. Specify the data source class and configure access to the new WCF Data Service. In the example below, the Access Rule for the entities is set to All. This means that any user will be able to read and modify data.

      
    using System;
    using System.Collections.Generic;
    using System.Data.Services;
    using System.Data.Services.Common;
    using System.Linq;
    using System.ServiceModel.Web;
    using System.Web;
    
    namespace APIService{
      public class APIDataService : DataService<APIEntities> {
        public static void InitializeService(DataServiceConfiguration config) {
          config.SetEntitySetAccessRule("*", EntitySetRights.All);
          config.DataServiceBehavior.MaxProtocolVersion = DataServiceProtocolVersion.V3;
        }
      }
    }
    	

12. Run the project. Applications that support OData can now access the Salesforce data and reflect any changes. You can access the feed in your browser. The feed will resemble the following:

Consume the OData Service from Power Pivot

You can now use the service from any OData client; for example, Excel Power Pivot.

1. Open Excel and click on the Power Pivot Window button.
2. A new pop-up will appear. Select the option From Data Feeds.
3. In the resulting Table Import Wizard, enter the OData URL. For example, http://localhost:12449/APIDataService.svc/.
4. After connecting to the OData service, click the Next button at the bottom of the window.
5. A table listing of the available tables will appear in the next window of the wizard. Select which tables you want to import and click Finish.
6. Click Close to import the data in Power Pivot.