Make sure project updates run in default EE (#9172)

* Make sure project updates run in default EE

* Remove project execution_environment field from collection

awx/api/serializers.py

@@ -1394,7 +1394,7 @@ class ProjectSerializer(UnifiedJobTemplateSerializer, ProjectOptionsSerializer):
 
     class Meta:
         model = Project
-        fields = ('*', 'organization', 'scm_update_on_launch',
+        fields = ('*', '-execution_environment', 'organization', 'scm_update_on_launch',
                   'scm_update_cache_timeout', 'allow_override', 'custom_virtualenv', 'default_environment') + \
                  ('last_update_failed', 'last_updated')  # Backwards compatibility
 

awx/main/models/mixins.py

@@ -455,12 +455,17 @@ class ExecutionEnvironmentMixin(models.Model):
         help_text=_('The container image to be used for execution.'),
     )
 
+    def get_execution_environment_default(self):
+        from awx.main.models.execution_environments import ExecutionEnvironment
+
+        if settings.DEFAULT_EXECUTION_ENVIRONMENT is not None:
+            return settings.DEFAULT_EXECUTION_ENVIRONMENT
+        return ExecutionEnvironment.objects.filter(organization=None, managed_by_tower=True).first()
+
     def resolve_execution_environment(self):
         """
         Return the execution environment that should be used when creating a new job.
         """
-        from awx.main.models.execution_environments import ExecutionEnvironment
-
         if self.execution_environment is not None:
             return self.execution_environment
         if getattr(self, 'project_id', None) and self.project.default_environment is not None:
@@ -470,9 +475,8 @@ class ExecutionEnvironmentMixin(models.Model):
         if getattr(self, 'inventory', None) and self.inventory.organization is not None:
             if self.inventory.organization.default_environment is not None:
                 return self.inventory.organization.default_environment
-        if settings.DEFAULT_EXECUTION_ENVIRONMENT is not None:
-            return settings.DEFAULT_EXECUTION_ENVIRONMENT
-        return ExecutionEnvironment.objects.filter(organization=None, managed_by_tower=True).first()
+
+        return self.get_execution_environment_default()
 
 
 class CustomVirtualEnvMixin(models.Model):

awx/main/models/projects.py

@@ -187,6 +187,14 @@ class ProjectOptions(models.Model):
                 pass
         return cred
 
+    def resolve_execution_environment(self):
+        """
+        Project updates, themselves, will use the default execution environment.
+        Jobs using the project can use the default_environment, but the project updates
+        are not flexible enough to allow customizing the image they use.
+        """
+        return self.get_execution_environment_default()
+
     def get_project_path(self, check_if_exists=True):
         local_path = os.path.basename(self.local_path)
         if local_path and not local_path.startswith('.'):