A Drupal Recipe for Linking Content Types via Titles and URLs

On a current project, I discovered the truth to the phrase in the Drupal community of "there's a module for that". As I initially looked at what I needed to do for a requirement, I was thinking that I would need to write a small amount of custom code in a glue module, but upon doing more research, I discovered that there were multiple modules that, when pieced together, would do exactly what I needed. And of course, as always, I knew I had to blog about it. Please raise your hand if you have any questions.

First, the use case. I had two content types that needed to be linked together: Video and Transcript. As you can probably tell from the name, the Transcript node is a written transcript of the content of the Video node. For the URL of the Video node, I wanted to use the associated term from a specific taxonomy called Category as part of the URL so that the URL was in the form of

For the Transcript node, I wanted it to be obvious from the URL that it was associated with the specific Video node, so for the video above, it would take the form of

In addition to this, I wanted to make it easy for the user to add a transcript to a video node, and also for the Video and Transcript nodes to be linked to each other.

Here are the modules used for this recipe:

• Token
• Taxonomy Token
• Nodereference CCK
• Nodereference URL
• Views Attach
• Automatic Nodetitles

The first step is to create the URL alias for the Video nodes. Out of the box, Token provides a [term] (and corresponding [term-raw]) token, but the results of these are inconsistent (I never really did any research into how those tokens are filled). I chatted briefly with greggles in IRC, and his thought was that it would be easiest to write a custom token (and also better for performance), because that way it could be targeted to the specific vocabulary. Upon doing some research in the Token issue queue, I found the Taxonomy Token module. This allows you to create tokens for specific taxonomy terms in specific vocabularies.

In the picture above, I'm creating single top term tokens for the Category vocabulary. This then creates the [node:vocab:1:term:url] token, and I can then create my URL alias for Video nodes as

So, in the case of the video above with the term National from the Category vocabulary, the URL would be

I'll get back to creating the alias for the Transcript node, but we have to complete some other steps first.

Next, we need to link the Video and Transcript nodes. I don't need to go into great detail here, because Bob Christenson at Mustardseed Media has a great video that demonstrates how to use Nodereference URL and Views Attach to link the two nodes together. In my use case, I end up with a link on my Video node to add a new Transcript node. Clicking on that link takes me directly to the node/add/transcript page. The node title for the Transcript node is automatically generated, and when it is saved, there is a link on the Transcript node to the Video node and vice versa.

Next is creating the title of the Transcript node. What I wanted was to have the title of the Transcript node by the title of the Video node with ' - Transcript' attached (i.e. My Video Node Title - Transcript). As explained in the video, the two content types are linked together by a nodereference field (field_video_ref) in the Transcript node type that refers to the Video node. This creates a [field_video_ref-title-raw] token that I can use. I enable the Automatic Nodetitles module, which adds an "Automatic Title generation" text form group on my content type settings form. Using my handy dandy token, I set the value in the Pattern for the Title" field to be

and select the "Automatically generate the title and hide the title field" option. When I go to create the Transcript node, the Title field is hidden, but the node title is correctly created when it is saved.

The last requirement to take care of is the URL alias for the Transcript node. As I said above, I want the alias to be the same as the alias for the Video node with '/transcript' appended to the end. Once again, Token module comes to the rescue. Since I am using the field_video_ref field, there are a number of tokens generated for that field:

In my case, I want the [field_video_ref-path] token, since that gives me video/national/my-video-node-title, making my full Transcript alias [field_video_ref-path]/transcript.

Now that this is all in place, here's the functionality that I have:

• The Video node URL alias is generated using a specific taxonomy vocabulary
• A link to create a Transcript node from the Video node
• A link to the finished Transcript node on the Video node and vice versa
• The Transcript node title and URL alias generated based on the title and URL of the Video node.

And all of this without writing one line of custom code in a module. All of this demonstrates the power of Token module and how it gives you so many options to automatically generate URLs, titles, and many other pieces of information for you automatically based on specific criteria.

On a side note, the (valid) question could be asked "why not just put a text area in the Video node for the transcript?", and that would be valid. However, don't let that distract from the point of this post, which is to demonstrate the power and flexibility that putting a few modules together gives you out of the box (so to speak) with Drupal.