customizing django admin ChangeForm template / adding custom content

Question

I'm able to insert (lame) static text onto the change form admin page, but I'd really like it to use the context of the current object being edited!

For instance, I want to format on the MyObject change form a URL to include the ID from a ForeignKey connected object (obj) as a link.

My admin objects:

class MyObjectChangeForm(forms.ModelForm):
    class Meta:
        model = MyObject
        fields = ('field1', 'obj',)

class MyObjectAdmin(admin.ModelAdmin):
    form = MyObjectChangeForm
    list_display = ('field1', 'obj')
    def render_change_form(self, request, context, *args, **kwargs):
        self.change_form_template = 'admin/my_change_form.html'
        extra = {'lame_static_text': "something static",}
        context.update(extra)
        return super(MyObjectAdmin, self).render_change_form(request,
            context, *args, **kwargs)

My template templates/admin/my_change_form.html:

{% extends "admin/change_form.html" %}

{% block form_top %}
    {{ lame_static_text }}
    <a href="http://example.com/abc/{{ adminform.data.obj.id }}?"/>View Website</a>
{% endblock %}

The {{adminform.data.obj.id}} call obviously doesn't work, but I'd like something along those lines.

How do I insert dynamic context from the current object into the admin change form?

Answer 1

Add your extra context in change_view

class MyObjectAdmin(admin.ModelAdmin):

    # A template for a very customized change view:
    change_form_template = 'admin/my_change_form.html'

    def get_dynamic_info(self):
        # ...
        pass

    def change_view(self, request, object_id, form_url='', extra_context=None):
        extra_context = extra_context or {}
        extra_context['osm_data'] = self.get_dynamic_info()
        return super(MyObjectAdmin, self).change_view(
            request, object_id, form_url, extra_context=extra_context,
        )

Answer 2

I believe the magic variable you seek is 'original', this contains the python object the change form is editing:

<a href="http://example.com/abc/{{ original.id }}?"/>View Website</a>