OData is an easy to use protocol that provides access to any data defined as an OData service provider. Microsoft Open Technologies, Inc., is collaborating with several other organizations and individuals in development of the OData standard in the OASIS OData Technical Committee, and the growing OData ecosystem is enabling a variety of new scenarios to deliver open data for the open web via standardized URI query syntax and semantics. To learn more about OData, including the ecosystem, developer tools, and how you can get involved, see this blog post.
In this post I’ll take you through the steps to set up Drupal on Windows Azure as an OData provider. As you’ll see, this is a great way to get started using both Drupal and OData, as there is no coding required to set this up.
It also won’t cost you any money – currently you can sign up for a 90 day free trial of Windows Azure and install a free Web development tool (Web Matrix) and a free source control tool (Git) on your local machine to make this happen, but that’s all that’s required from a client point of view. We’ll also be using a free tier for the Drupal instance, so you may not need to pay even after the 90 day trial, depending on your needs for bandwidth or storage.
So let’s get started!
Set up a Drupal instance on Windows Azure using the Web Gallery.
The Windows Azure team has made setting up a Drupal instance incredibly easy and quick – in a few clicks and a few minutes your site will be up and running. Once you’ve signed up for Windows Azure and have your account set up, click on New > Quick Create > from Gallery, as shown here:
Then click on the Drupal 7 instance, as shown here. The Web Gallery is where you’ll find images of the latest Web applications, preconfigured and ready to set up. Currently we’re using the Acquia version of Drupal 7 for Drupal:
Enter some basic information about your site, including the URL (.azurewebsites.net will be added on t what you choose), the type of database you want to work with (currently SQL Server and MySQL are supported for Drupal), the region you want your app instance deployed :
Next, add a database name, username and password for the database, and a region that the database should be deployed :
That’s it! In a few minutes your Windows Azure Web Site dashboard will appear with options for monitoring and working with your new Drupal instance:
Setting up the OData provider
So far we have a Drupal instance but it’s not an OData provider yet. To get Drupal set up as an OData provider, we’re going to have to add a few folders and files, and configure some Drupal modules.
Because good cloud systems protect your data by backing it up and providing seamless, invisible redundancy, working with files in the cloud can be tricky. But the Windows Azure team provide a free, easy to use tool to work with files on Windows azure, called Web Matrix. Web Matrix lets you easily download your files, work with them locally, test your work and publish changes back up to your site when you’re ready. It’s also a great development tool that supports most modern Web application development languages.
Once you’ve downloaded and installed Web Matrix on your local machine, you simply click on the Web Matrix icon on the bottom right under the dashboard, as show in the image above. Web Matrix will confirm that you want to make a local copy of your Windows Azure Web site and download the site:
Web Matrix will detect the type of Web site you’re working with, set up a local instance Database and start downloading the Web site to the instance:
When Web Matrix is done downloading your site you’ll see a dashboard showing you options for working with your local site. For this example, we’re only going to be working with files locally, so click the files icon shown here:
We need to add some libraries and modules to our Drupal Instance to make the Windows Azure standard configuration of Drupal 7 become an OData provider. There are three sets of files we need to download and place in specific places in our instance. You’ll need Git, or your favorite Git-compatible tool installed on your local machine to retrieve some of these files:
1) Download the OData Producer Library for PHP V1.2 to your local machine from https://github.com/MSOpenTech/odataphpprod/
Under the sites > all folder, create a folder called libraries> odata (create the libraries folder if it doesn’t exist ) and copy in the downloaded files.
2) Download version 2 of the Drupal Libraries API from your local machine from http://drupal.org/project/libraries
Under the sites > all folder, create a folder called modules > libraries (yes, there are two libraries directories in different places) and copy in the downloaded files.
3) Download r2integrated's OData Server files to your local machine from //git.drupal.org/sandbox/r2integrated/1561302.git
Under the sites > all folder, create a folder called modules > odata_server and copy in the downloaded files.
Here’s what the directories should look like when you’re done:
Next, click on the Publish button, to upload the new files to your Windows Azure Web site via WebMatrix. After a few minutes your files should be loaded up and ready to use.
OData Configuration in Drupal on Windows Azure
Next, we will configure the files we just uploaded to provide data to OData clients.
From the top Menu, Go to the Drupal modules, and navigate down to the “other”section.
Enable Libraries and OData Server, then save configuration. The modules should look like this when you’re done:
Next, go to Site Configuration from the top menu, and navigate down to the Development section. Under development, click on OData Settings
Under Node, enable page and or article, (click on expose then to OData clients), the select the fields from each Node you want to return in an OData search. You can also return Comments, Files, Taxonomy Terms, Taxonomy Vocabularies, and Users. All are off by default and have to be enabled to expose properties, fields, and references through the OData server:
Click Save Configuration and you’re ready to start using your Windows Azure Drupal Web site as an OData provider!
One last thing - unfortunately, the default data in Drupal consists of exactly one page, so search results are not too impressive. You’ll probably want to add some data to make the site useful as an OData provider. The best way to do that is via the Drupal feeds module.
As promised at the beginning of this post, we’ve now created an OData provider based on Drupal to deliver open data for the open Web. From here any OData consumer can consume the OData feed and doesn’t have to know anything about the underlying data source, or even that it’s Drupal on the back end. The consumers simply see it as an OData service provider. Of course there’s more effort involved in getting your data imported, organizing it and building OData clients to consume the data, but this is a great start with minimal effort using existing, free tools.