Importing tags with Groovy

In this post I use a Groovy script to import custom tags into Magnolia CMS. The script saves the tags in the Data module. You can use them to categorize pages, images and documents.

Clients often ask me how to import an existing collection of tags into Magnolia CMS. Local governments use tags such as taxes, transportation or schools to categorize their content. Travel websites use geographical terms like london, paris and bangkok to tag places to visit. Such vocabularies grow large over time. Creating them from scratch is a lot of work.

I wrote a Groovy script that imports tags from XML. The example below finds any Flickr tags that are related to the given tag london. You can customize the script to import your own tags. I am not sure why I had not used Groovy much before. Once I tried it I loved it! You will too when you see how simple it is to implement a tag importer.

Requirements

• Magnolia CMS 4.5.7 with Groovy module. It's in the add-ons folder in the bundle.
• Flickr API key. Register for an API key in order to call the Flickr API.

Creating a Groovy script

1. In Magnolia CMS, go to Tools > Scripts and add a new Groovy script.
2. Paste the following code into your script.
3. Check the Is a script? box.

tag = 'london'
hm = MgnlContext.getHierarchyManager('data')

// Create a folder in the Data module
flickrTags = ContentUtil.createPath(hm, "/categorization/${tag}", new ItemType("dataFolder"))
hm.save()
itemType = new ItemType('category')

// Connect to Flickr REST API
URL url = new URL("http://api.flickr.com/services/rest/?method=flickr.tags.getRelated&api_key=5f26c50b6e67110809b117da0f2bb94f&tag=${tag}")

HttpURLConnection conn = (HttpURLConnection) url.openConnection()
    conn.setRequestMethod("GET")
    conn.setRequestProperty("Accept", "application/xml")

 if (conn.getResponseCode() != 200) {
   throw new RuntimeException("Failed : HTTP error code : "
   + conn.getResponseCode())
 }

// Parse the response XML 
rsp = new XmlSlurper().parse(conn.getInputStream())
rsp.tags.tag.each{
      content = ContentUtil.createPath(hm, "/categorization/${tag}/${it.text()}", itemType)
      content.name = it.text()
}

flickrTags.save()
conn.disconnect()
return "done"

Here's what the script does:

1. Create a new folder in the Data module with the parent tag name.
2. Connect to the Flickr REST API and request all tags related to the parent tag.
3. Parse the resulting XML.
4. Create categories under the previously created data folder.

Now the tags are available for categorizing content.

Bear in mind is that there is no error handling in this code to keep it short. This solution has been developed and tested with Magnolia 4.5.7

Adding Flickr images to Magnolia CMS

This is a step-by-step guide on how to create your custom DAM and plug it into Magnolia CMS. Will allow you to add images from external services like Flickr, as well as adding images from other servers using their url (It comes with a forge module!)

This is a sample handle for external image/video urls, very basic as it does not add the imaging support for now.

* Requirements - Standard Templating Kit Module

1. The Asset

We need to create our own Asset class that will implement the interface Asset

If we want to have exact same behavior as in STK/ETK we will need to find a way to store 'meta data' (caption, description) of our assets, we could use the data module for that matter.

In this sample we wont store any metadata for the images, nor use the imaging support.

That leaves us with just one method to implement 'getLink' and this will be the value stored when we open the dialog to select an image.

public String getLink() throws DAMException {
return link;
}

Creation of link is on the class constructor, as easy as this

link = nodeData.getString();



2. The handler.

Should extend class AbstractHandler . We will extend from AbstractHandler that has the methods to read the configuration, that leaves us with two methods to implement as needed: getAsset and getAssetByKey. In this case we implement getAsset to return an instance of our Asset.

final String name = getNodeDataName(node, nodeDataPrefix);

Important thing to note here is that we need to get the name of the nodeData that has the url of our image. When you set an image using the dam controls, you name your node as i.e. 'myimage' and on saving you will get a nodeData with the name you gave plus the name of the dam control used. To make it simpler a call to the method getNodeDataName will give you the real name with which your node has been saved. In this sample it will contain the exact url of our image, no need of further processing.

final NodeData nodeData = node.getNodeData(name);

This line above gets the node data, now with the right name.

return new UrlAsset(nodeData);

Here is where we return our asset.

3. The controls (configuration).

Need to add the configuration for this external dam. For that we create a new node under our site configuration. There we put the handler we are going to use and the control/s in which we will store the image information. See image:




And to finish this post there is a module in Magnolia forge magnolia-module-urldam with the code to add an external dam handler.