How to add free-form tags to a CKAN package?

Question

I'm trying to figure out how to add free-form (vocabulary-free) tags to a package programmatically, and I'm finding the documentation a little confusing.

from http://docs.ckan.org/en/latest/ckan.logic.action.create.html package_create says I can add tags and "see tag_create() for the format of tag dictionaries"

tag_create says "To create a new free tag simply add the tag to a package, e.g. using the package_update function"

from http://docs.ckan.org/en/latest/ckan.logic.action.update.html package_update doesn't really specify how to use it, so I tried:

package_update({"id": "my-package-id", "tags": [ "some", "free", "tags"]})

However that complains that it wants tags in dictionary format, as I would use for specifying tags that are part of a vocabulary. How do I specify a free tag?

Also, what is the best way to access the tags once I have them entered? I ran into a situation where my_package.package_tags contained a tag, but my_package.get_tags() returned an empty list?

Thanks so much!!

Answer 1

You may create a new tag simply by doing a package_create() or package_update() and specifying a tag that doesn't exist yet, and I think (guessing) the correct format for the "tags" param to package_create() or package_update() should be:

"tags": [{"name": "my_tag"}, {"name": "my-other-tag"}]

But you would have to test that.

However that complains that it wants tags in dictionary format, as I would use for specifying tags that are part of a vocabulary. How do I specify a free tag?

So as above, just the same dictionary format as for a vocab tag but with only the "name" key and no "vocabulary_id".

Also, what is the best way to access the tags once I have them entered? I ran into a situation where my_package.package_tags contained a tag, but my_package.get_tags() returned an empty list?

Use the action functions: package_show(), tag_list(), tag_show(), etc.

If you're writing a CKAN extension and you don't want to call CKAN's action functions by making HTTP requests, then you should interact with CKAN using the "plugins toolkit" which includes a way to call action functions like this:

import ckan.plugins.toolkit as tk
my_package = tk.get_action('package_show')({'id': 'my_package'})

You'll find lots of other useful stuff in the toolkit.