rrs: default python2/3 environments for new maintenance plan layer branches

It's a bit of a pain to have to set the two python environment fields on
every record in order to have things set correctly, and it can easily
get forgotten, so try to set them automatically by default (assuming
reasonable naming).

Note that this does introduce an annoying behaviour whereby if you click
"Add another Maintenance plan layer branch" and then decide you don't
want it, the admin form will insist you fill in the fields unless you
clear out the python2/3 environment fields. I'm not sure how to fix
that, so I'm leaving it as-is for now.

Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com>

layerindex/models.py

@@ -47,6 +47,20 @@ class PythonEnvironment(models.Model):
             cmd = self.python_command
         return cmd
 
+    @staticmethod
+    def get_default_python2_environment():
+        for env in PythonEnvironment.objects.all().order_by('id'):
+            if env.name.replace(' ', '').lower().startswith(('python2', 'py2')):
+                return env
+        return None
+
+    @staticmethod
+    def get_default_python3_environment():
+        for env in PythonEnvironment.objects.all().order_by('id'):
+            if env.name.replace(' ', '').lower().startswith(('python3', 'py3')):
+                return env
+        return None
+
     def __str__(self):
         return self.name
 

rrs/admin.py

@@ -4,16 +4,46 @@
 #
 # Licensed under the MIT license, see COPYING.MIT for details
 
+from django.utils.functional import curry
+
 from django.contrib import admin
 from django.contrib.admin import DateFieldListFilter
+from django.forms.models import BaseInlineFormSet
 
 from rrs.models import Release, Milestone, Maintainer, RecipeMaintainerHistory, \
         RecipeMaintainer, RecipeDistro, RecipeUpgrade, RecipeUpstream, \
         RecipeUpstreamHistory, MaintenancePlan, MaintenancePlanLayerBranch, \
         RecipeMaintenanceLink
 
+class MaintenancePlanLayerBranchFormSet(BaseInlineFormSet):
+    def __init__(self, *args, **kwargs):
+        from layerindex.models import PythonEnvironment
+        initialfields = {}
+        py2env = PythonEnvironment.get_default_python2_environment()
+        if py2env:
+            initialfields['python2_environment'] = py2env.id
+        py3env = PythonEnvironment.get_default_python3_environment()
+        if py3env:
+            initialfields['python3_environment'] = py3env.id
+        if initialfields:
+            kwargs['initial'] = [initialfields]
+        super(MaintenancePlanLayerBranchFormSet, self).__init__(*args, **kwargs)
+
+    @property
+    def empty_form(self):
+        from layerindex.models import PythonEnvironment
+        form = super(MaintenancePlanLayerBranchFormSet, self).empty_form
+        py2env = PythonEnvironment.get_default_python2_environment()
+        if py2env:
+            form.fields['python2_environment'].initial = py2env
+        py3env = PythonEnvironment.get_default_python3_environment()
+        if py3env:
+            form.fields['python3_environment'].initial = py3env
+        return form
+
 class MaintenancePlanLayerBranchInline(admin.StackedInline):
     model = MaintenancePlanLayerBranch
+    formset = MaintenancePlanLayerBranchFormSet
     readonly_fields = ['upgrade_date', 'upgrade_rev']
     min_num = 1
     extra = 0