Refactor to make pagination reusable

The responses we get to paginated queries from the API are fairly
consistent, so we should be able to reuse the code that takes JSON
from the API and turns it into Python objects. This commits factors out
that code so that it is reusable (by inheriting from it).

app/models/__init__.py

@@ -41,3 +41,22 @@ class ModelList(SerialisedModelCollection):
 
     def __init__(self, *args):
         self.items = self.client_method(*args)
+
+
+class PaginatedModelList(ModelList):
+
+    response_key = 'data'
+
+    def __init__(self, *args, page=None, **kwargs):
+        try:
+            self.current_page = int(page)
+        except TypeError:
+            self.current_page = 1
+        response = self.client_method(
+            *args,
+            **kwargs,
+            page=self.current_page,
+        )
+        self.items = response[self.response_key]
+        self.prev_page = response.get('links', {}).get('prev', None)
+        self.next_page = response.get('links', {}).get('next', None)

app/models/job.py

@@ -9,7 +9,7 @@ from notifications_utils.letter_timings import (
 from notifications_utils.timezones import utc_string_to_aware_gmt_datetime
 from werkzeug.utils import cached_property
 
-from app.models import JSONModel, ModelList
+from app.models import JSONModel, ModelList, PaginatedModelList
 from app.notify_client.job_api_client import job_api_client
 from app.notify_client.notification_api_client import notification_api_client
 from app.notify_client.service_api_client import service_api_client
@@ -25,6 +25,7 @@ class Job(JSONModel):
     ALLOWED_PROPERTIES = {
         'id',
         'service',
+        'template_name',
         'template_version',
         'original_file_name',
         'created_at',
@@ -230,20 +231,12 @@ class ScheduledJobs(ImmediateJobs):
     client_method = job_api_client.get_scheduled_jobs
 
 
-class PaginatedJobs(ImmediateJobs):
-
+class PaginatedJobs(PaginatedModelList, ImmediateJobs):
     client_method = job_api_client.get_page_of_jobs
 
-    def __init__(self, service_id, page=None):
-        try:
-            self.current_page = int(page)
-        except TypeError:
-            self.current_page = 1
-        response = self.client_method(service_id, page=self.current_page)
-        self.items = response['data']
-        self.prev_page = response.get('links', {}).get('prev', None)
-        self.next_page = response.get('links', {}).get('next', None)
+    def __init__(self, service_id, *, page=None):
+        super().__init__(service_id, page=page)
 
 
-class PaginatedUploads(PaginatedJobs):
+class PaginatedUploads(PaginatedModelList, ImmediateJobs):
     client_method = job_api_client.get_uploads