Merge pull request #329 from ckan/decouple-structured_data

Decouple `dcat` and `structured_data` plugins

ckanext/dcat/blueprints.py

@@ -1,12 +1,13 @@
 # -*- coding: utf-8 -*-
-from flask import Blueprint, jsonify, make_response
+from flask import Blueprint, jsonify
 
 from ckantoolkit import config
 
 from ckan.views.dataset import CreateView
 
 import ckan.plugins.toolkit as toolkit
 import ckanext.dcat.utils as utils
+from ckanext.dcat.helpers import endpoints_enabled
 
 dcat = Blueprint(
     'dcat',
@@ -23,7 +24,7 @@ def read_dataset(_id, _format=None, package_type=None):
     return utils.read_dataset_page(_id, _format)
 
 
-if utils.endpoints_enabled():
+if endpoints_enabled():
 
     # requirements={'_format': 'xml|rdf|n3|ttl|jsonld'}
     dcat.add_url_rule(config.get('ckanext.dcat.catalog_endpoint',

ckanext/dcat/helpers.py

@@ -0,0 +1,52 @@
+"""
+Helpers used by templates
+"""
+import simplejson as json
+
+import ckantoolkit as toolkit
+
+from ckanext.dcat.processors import RDFSerializer
+
+config = toolkit.config
+
+
+ENABLE_RDF_ENDPOINTS_CONFIG = "ckanext.dcat.enable_rdf_endpoints"
+
+
+def endpoints_enabled():
+    return toolkit.asbool(config.get(ENABLE_RDF_ENDPOINTS_CONFIG, True))
+
+
+def get_endpoint(_type="dataset"):
+    return "dcat.read_dataset" if _type == "dataset" else "dcat.read_catalog"
+
+
+def structured_data(dataset_dict, profiles=None, _format="jsonld"):
+    """
+    Returns a string containing the structured data of the given
+    dataset id and using the given profiles (if no profiles are supplied
+    the default profiles are used).
+
+    This string can be used in the frontend.
+    """
+
+    if not profiles:
+        profiles = ["schemaorg"]
+
+    serializer = RDFSerializer(profiles=profiles)
+
+    output = serializer.serialize_dataset(dataset_dict, _format=_format)
+
+    # parse result again to prevent UnicodeDecodeError and add formatting
+    try:
+        json_data = json.loads(output)
+        return json.dumps(
+            json_data,
+            sort_keys=True,
+            indent=4,
+            separators=(",", ": "),
+            cls=json.JSONEncoderForHTML,
+        )
+    except ValueError:
+        # result was not JSON, return anyway
+        return output

ckanext/dcat/plugins/__init__.py

@@ -19,6 +19,7 @@
                                 dcat_datasets_list,
                                 dcat_auth,
                                 )
+from ckanext.dcat import helpers
 from ckanext.dcat import utils
 from ckanext.dcat.validators import dcat_validators
 
@@ -81,7 +82,7 @@ def i18n_directory(self):
     # IConfigurer
 
     def update_config(self, config):
-        p.toolkit.add_template_directory(config, '../templates')
+        p.toolkit.add_template_directory(config, '../templates/dcat')
 
         # Check catalog URI on startup to emit a warning if necessary
         utils.catalog_uri()
@@ -102,9 +103,8 @@ def update_config(self, config):
 
     def get_helpers(self):
         return {
-            'helper_available': utils.helper_available,
-            'dcat_get_endpoint': utils.get_endpoint,
-            'dcat_endpoints_enabled': utils.endpoints_enabled,
+            'dcat_get_endpoint': helpers.get_endpoint,
+            'dcat_endpoints_enabled': helpers.endpoints_enabled,
         }
 
     # IActions
@@ -243,11 +243,18 @@ def get_auth_functions(self):
 
 
 class StructuredDataPlugin(p.SingletonPlugin):
+
+    p.implements(p.IConfigurer, inherit=True)
     p.implements(p.ITemplateHelpers, inherit=True)
 
+    # IConfigurer
+
+    def update_config(self, config):
+        p.toolkit.add_template_directory(config, '../templates/structured_data')
+
     # ITemplateHelpers
 
     def get_helpers(self):
         return {
-            'structured_data': utils.structured_data,
+            'structured_data': helpers.structured_data,
         }

ckanext/dcat/templates/package/read_base.html → ckanext/dcat/templates/dcat/package/read_base.html

@@ -12,20 +12,3 @@
       {% endwith %}
     {% endif %}
 {% endblock -%}
-{% block scripts %}
-  {{ super() }}
-  {% block structured_data %}
-    {#
-    h.structured_data is defined in the 'structured_data' plugin,
-    you have to activate the plugin (or implement the method yourself)
-    to make use of this feature.
-    More information about structured data:
-    https://developers.google.com/search/docs/guides/intro-structured-data
-    #}
-      {% if h.helper_available('structured_data') %}
-          <script type="application/ld+json">
-           {{ h.structured_data(pkg.id)|safe }}
-          </script>
-      {% endif %}
-  {% endblock %}
-{% endblock %}

ckanext/dcat/templates/structured_data/package/read_base.html

@@ -0,0 +1,13 @@
+{% ckan_extends %}
+
+{% block scripts %}
+
+  {{ super() }}
+
+  {% block structured_data %}
+    <!-- Structured data -->
+    <script type="application/ld+json">
+      {{ h.structured_data(pkg) | safe }}
+    </script>
+  {% endblock %}
+{% endblock %}

ckanext/dcat/utils.py

@@ -37,7 +37,6 @@
 DCAT_CLEAN_TAGS = 'ckanext.dcat.clean_tags'
 
 DEFAULT_CATALOG_ENDPOINT = '/catalog.{_format}'
-ENABLE_RDF_ENDPOINTS_CONFIG = 'ckanext.dcat.enable_rdf_endpoints'
 ENABLE_CONTENT_NEGOTIATION_CONFIG = 'ckanext.dcat.enable_content_negotiation'
 
 
@@ -95,43 +94,6 @@ def field_labels():
         'created': _('Created'),
     }
 
-def helper_available(helper_name):
-    '''
-    Checks if a given helper name is available on `h`
-    '''
-    try:
-        getattr(h, helper_name)
-    except (AttributeError, HelperError):
-        return False
-    return True
-
-def structured_data(dataset_id, profiles=None, _format='jsonld'):
-    '''
-    Returns a string containing the structured data of the given
-    dataset id and using the given profiles (if no profiles are supplied
-    the default profiles are used).
-
-    This string can be used in the frontend.
-    '''
-    if not profiles:
-        profiles = ['schemaorg']
-
-    data = toolkit.get_action('dcat_dataset_show')(
-        {},
-        {
-            'id': dataset_id,
-            'profiles': profiles,
-            'format': _format,
-        }
-    )
-    # parse result again to prevent UnicodeDecodeError and add formatting
-    try:
-        json_data = json.loads(data)
-        return json.dumps(json_data, sort_keys=True,
-                          indent=4, separators=(',', ': '), cls=json.JSONEncoderForHTML)
-    except ValueError:
-        # result was not JSON, return anyway
-        return data
 
 def catalog_uri():
     '''
@@ -459,11 +421,3 @@ def read_catalog_page(_format):
     response.headers['Content-type'] = CONTENT_TYPES[_format]
 
     return response
-
-
-def endpoints_enabled():
-    return toolkit.asbool(config.get(ENABLE_RDF_ENDPOINTS_CONFIG, True))
-
-
-def get_endpoint(_type='dataset'):
-    return 'dcat.read_dataset' if _type == 'dataset' else 'dcat.read_catalog'

docs/google-dataset-search.md

@@ -2,18 +2,22 @@
 
 The `structured_data` plugin will add the necessary markup to dataset pages in order to get your datasets indexed by [Google Dataset Search](https://toolbox.google.com/datasetsearch). This markup is a [structured data](https://developers.google.com/search/docs/guides/intro-structured-data) JSON-LD snippet that uses the [schema.org](https://schema.org) vocabulary to describe the dataset.
 
-    ckan.plugins = dcat structured_data
+    ckan.plugins = structured_data
 
-By default this uses the `schemaorg` profile (see [Profiles](profiles.md#profiles)) to serialize the dataset to JSON-LD, which is then added to the dataset detail page.
-To change the schema, you have to override the Jinja template block called `structured_data` in [`templates/package/read_base.html`](https://github.com/ckan/ckanext-dcat/blob/master/ckanext/dcat/templates/package/read_base.html) and call the template helper function with different parameters:
+You don't need to load the `dcat` plugin to use the `structured_data` plugin, but you can load them both to enable both functionalities.
+
+The plugin uses the `schemaorg` profile by default (see [Profiles](profiles.md#profiles)) to serialize the dataset to JSON-LD, which is then added to the dataset detail page.
+
+To use a custom profile, you have to override the Jinja template block called `structured_data` in [`templates/package/read_base.html`](https://github.com/ckan/ckanext-dcat/blob/master/ckanext/dcat/templates/structured_data/package/read_base.html) and call the template helper function with different parameters:
 
     {% block structured_data %}
       <script type="application/ld+json">
-      {{ h.structured_data(pkg.id, ['my_custom_schema'])|safe }}
+      {{ h.structured_data(pkg, ['my_custom_schema']) | safe }}
       </script>
     {% endblock %}
 
-Example output of structured data in JSON-LD:
+
+Below is an example of the structured data in JSON-LD embedded in the dataset page source:
 
 ```html
     <script type="application/ld+json">