Customize a geonode project model

In this section, we will patch the ResourceBase of GeoNode and update the templates in order to add one more field to the Metadata Schema.

We will add a custom_md field to the ResourceBase model and modify the templates in order to show the new field both into the Metadata Wizard and the Layer Details page.

Activate the virtualenv

We should already be working in the right directory, and with the proper venv activated. If not, run:

workon my_geonode
cd /opt/geonode-project/my_geonode/

• Update the GeoNode ResourceBase model

vim /opt/geonode/geonode/base/models.py

{% raw %}

diff --git a/geonode/base/models.py b/geonode/base/models.py
index e2a5a409c..922c67db4 100644
--- a/geonode/base/models.py
+++ b/geonode/base/models.py
@@ -706,6 +706,7 @@ class ResourceBase(PolymorphicModel, PermissionLevelMixin, ItemBase):
     data_quality_statement_help_text = _(
         'general explanation of the data producer\'s knowledge about the lineage of a'
         ' layer')
+    custom_md_help_text = _('a custom metadata field')
     # internal fields
     uuid = models.CharField(max_length=36)
     title = models.CharField(_('title'), max_length=255, help_text=_(
@@ -959,6 +960,13 @@ class ResourceBase(PolymorphicModel, PermissionLevelMixin, ItemBase):
     __is_approved = False
     __is_published = False
 
+
+    custom_md = models.TextField(
+        _("Custom Md"),
+        blank=True,
+        null=True,
+        help_text=custom_md_help_text)
+
     objects = ResourceBaseManager()
 
     class Meta:

{% endraw %}

• Add the new field to the DB

./manage_dev.sh makemigrations
./manage_dev.sh migrate

• Add the new field to templates

mkdir my_geonode/templates/layouts/
cp /opt/geonode/geonode/layers/templates/layouts/panels.html my_geonode/templates/layouts/panels.html

vim my_geonode/templates/layouts/panels.html

{% raw %}

--- /opt/geonode/geonode/layers/templates/layouts/panels.html	2021-09-01 14:22:59.778823091 +0100
+++ my_geonode/templates/layouts/panels.html	2021-09-10 15:48:39.691395977 +0100
@@ -317,6 +317,10 @@
                                 </div>
                                 {% endblock thumbnail %}
                                 <div class="col-lg-4">
+                                    <div id="req_item">
+                                      <span><label for="{{ layer_form.custom_md|id }}">{{ layer_form.custom_md.label }}</label></span>
+                                      {{ layer_form.custom_md }}
+                                    </div>
                                     {% block layer_title %}
                                     <div id="req_item">
                                       <span><label for="{{ layer_form.title|id }}">{{ layer_form.title.label }}</label></span>

{% endraw %}

• Let’s check the changes

./paver_dev.sh start_django

• Update the custom_md text field to a rich HTML one

vim /opt/geonode/geonode/base/forms.py

{% raw %}

diff --git a/geonode/base/forms.py b/geonode/base/forms.py
index 48a0ef7f1..e0284988c 100644
--- a/geonode/base/forms.py
+++ b/geonode/base/forms.py
@@ -416,6 +416,10 @@ class ResourceBaseForm(TranslationModelForm):
         label=_("Data quality statement"),
         required=False,
         widget=TinyMCE())
+    custom_md = forms.CharField(
+        label=_("Custom Md"),
+        required=True,
+        widget=TinyMCE())
 
     owner = forms.ModelChoiceField(
         empty_label=_("Owner"),

{% endraw %}

Update the Layers Details Templates

• Copy the default GeoNode layer_details template

mkdir my_geonode/templates/layers
cp /opt/geonode/geonode/layers/templates/layers/layer_detail.html my_geonode/templates/layers/layer_detail.html

• Add the new field to the layer_details template

vim my_geonode/templates/layers/layer_detail.html

mkdir my_geonode/templates/base
cp /opt/geonode/geonode/base/templates/base/resourcebase_info_panel.html my_geonode/templates/base/resourcebase_info_panel.html

vim my_geonode/templates/base/resourcebase_info_panel.html

cp /opt/geonode/geonode/base/templates/base/_resourcebase_info_panel.html my_geonode/templates/base/_resourcebase_info_panel.html

vim my_geonode/templates/base/_resourcebase_info_panel.html

{% raw %}

--- /opt/geonode/geonode/base/templates/base/_resourcebase_info_panel.html	2021-07-14 14:38:25.391987680 +0100
+++ my_geonode/templates/base/_resourcebase_info_panel.html	2021-09-13 09:47:42.768337828 +0100
@@ -31,6 +31,11 @@
     <dd itemprop="description">{{ resource.abstract|safe }}</dd>
     {% endif %}
 
+    {% if resource.custom_md %}
+    <dt>{% trans "Custom Metadata" %}</dt>
+    <dd itemprop="description">{{ resource.custom_md|safe }}</dd>
+    {% endif %}
+
     {% if resource.date %}
     {% if resource.date_type == 'creation' %}
     <dt>{% trans "Creation Date" %}</dt>

{% endraw %}

API REST (v2)

• Let’s add the new custom_md field to the REST API of GeoNode

  The APIs are reachable through the endpoint: http://localhost:8000/api/v2/

  Looking at the http://localhost:8000/api/v2/resources you will notice that the new field we just added is not visible

  

• Modify the GeoNode base rest api endpoints in order to add the new field

vim /opt/geonode/geonode/base/api/serializers.py

{% raw %}

diff --git a/geonode/base/api/serializers.py b/geonode/base/api/serializers.py
index c1a5e8679..909aca07e 100644
--- a/geonode/base/api/serializers.py
+++ b/geonode/base/api/serializers.py
@@ -293,6 +293,7 @@ class ResourceBaseSerializer(BaseDynamicModelSerializer):
         self.fields['raw_data_quality_statement'] = serializers.CharField(read_only=True)
         self.fields['metadata_only'] = serializers.BooleanField()
         self.fields['processed'] = serializers.BooleanField(read_only=True)
+        self.fields['custom_md'] = serializers.CharField()
 
         self.fields['embed_url'] = EmbedUrlField()
         self.fields['thumbnail_url'] = ThumbnailUrlField()
@@ -325,7 +326,8 @@ class ResourceBaseSerializer(BaseDynamicModelSerializer):
             'popular_count', 'share_count', 'rating', 'featured', 'is_published', 'is_approved',
             'detail_url', 'embed_url', 'created', 'last_updated',
             'raw_abstract', 'raw_purpose', 'raw_constraints_other',
-            'raw_supplemental_information', 'raw_data_quality_statement', 'metadata_only', 'processed'
+            'raw_supplemental_information', 'raw_data_quality_statement', 'metadata_only', 'processed',
+            'custom_md'
             # TODO
             # csw_typename, csw_schema, csw_mdsource, csw_insert_date, csw_type, csw_anytext, csw_wkt_geometry,
             # metadata_uploaded, metadata_uploaded_preserve, metadata_xml,

{% endraw %}

• http://localhost:8000/api/v2/resources?filter{custom_md.isnull}=False

  

• More info about dynamic-rest filtering options can be found at: https://github.com/AltSchool/dynamic-rest#filtering

Next Section: Save changes to GitHub