Merge pull request #1237 from alphagov/multi-page-previews

Show all pages of a letter in the app

app/main/views/templates.py

@@ -8,6 +8,7 @@ from flask import (
     url_for,
     flash,
     abort,
+    json,
 )
 from flask_login import login_required, current_user
 from dateutil.parser import parse
@@ -72,15 +73,21 @@ def choose_template(service_id):
     admin_override=True, any_=True
 )
 def view_template(service_id, template_id):
+    template = service_api_client.get_service_template(service_id, template_id)['data']
+    page_count = None
+    if template['template_type'] == 'letter':
+        page_count, _, _ = TemplatePreview.from_database_object(template, filetype='json')
+        page_count = json.loads(page_count.decode('utf-8'))['count']
     return render_template(
         'views/templates/template.html',
         template=get_template(
-            service_api_client.get_service_template(service_id, template_id)['data'],
+            template,
             current_service,
             expand_emails=True,
             letter_preview_url=url_for('.view_template', service_id=service_id, template_id=template_id),
             show_recipient=True,
-        )
+            page_count=page_count,
+        ),
     )
 
 
@@ -92,7 +99,7 @@ def view_letter_template_preview(service_id, template_id, filetype):
         abort(404)
 
     db_template = service_api_client.get_service_template(service_id, template_id)['data']
-    return TemplatePreview.from_database_object(db_template, filetype)
+    return TemplatePreview.from_database_object(db_template, filetype, page=request.args.get('page'))
 
 
 def _view_template_version(service_id, template_id, version, letters_as_pdf=False):

app/template_previews.py

@@ -6,7 +6,7 @@ from app import current_service
 
 class TemplatePreview:
     @classmethod
-    def from_database_object(cls, template, filetype, values=None):
+    def from_database_object(cls, template, filetype, values=None, page=None):
         data = {
             'letter_contact_block': current_service['letter_contact_block'],
             'template': template,
@@ -14,16 +14,21 @@ class TemplatePreview:
             'dvla_org_id': current_service['dvla_organisation'],
         }
         resp = requests.post(
-            '{}/preview.{}'.format(current_app.config['TEMPLATE_PREVIEW_API_HOST'], filetype),
+            '{}/preview.{}{}'.format(
+                current_app.config['TEMPLATE_PREVIEW_API_HOST'],
+                filetype,
+                '?page={}'.format(page) if page else '',
+            ),
             json=data,
             headers={'Authorization': 'Token {}'.format(current_app.config['TEMPLATE_PREVIEW_API_KEY'])}
         )
         return (resp.content, resp.status_code, resp.headers.items())
 
     @classmethod
-    def from_utils_template(cls, template, filetype):
+    def from_utils_template(cls, template, filetype, page=None):
         return cls.from_database_object(
             template._template,
             filetype,
-            template.values
+            template.values,
+            page=page,
         )

app/utils.py

@@ -255,6 +255,7 @@ def get_template(
     show_recipient=False,
     expand_emails=False,
     letter_preview_url=None,
+    page_count=1,
 ):
     if 'email' == template['template_type']:
         return EmailPreviewTemplate(
@@ -276,6 +277,7 @@ def get_template(
             return LetterPDFLinkTemplate(
                 template,
                 preview_url=letter_preview_url,
+                page_count=int(page_count),
             )
         else:
             return LetterPreviewTemplate(

requirements.txt

@@ -28,5 +28,4 @@ notifications-python-client>=3.1,<3.2
 awscli>=1.11,<1.12
 awscli-cwlogs>=1.4,<1.5
 
-git+https://github.com/alphagov/notifications-utils.git@15.0.4#egg=notifications-utils==15.0.4
-
+git+https://github.com/alphagov/notifications-utils.git@16.0.0#egg=notifications-utils==16.0.0

tests/app/test_template_previews.py

@@ -1,30 +1,61 @@
+import pytest
+
+from functools import partial
 from unittest.mock import Mock
 from notifications_utils.template import LetterPreviewTemplate
 
 from app.template_previews import TemplatePreview
 
 
-def test_from_utils_template_calls_through(mocker, mock_get_service_letter_template):
+@pytest.mark.parametrize('partial_call, expected_page_argument', [
+    (partial(TemplatePreview.from_utils_template), None),
+    (partial(TemplatePreview.from_utils_template, page=99), 99),
+])
+def test_from_utils_template_calls_through(
+    mocker,
+    mock_get_service_letter_template,
+    partial_call,
+    expected_page_argument,
+):
     mock_from_db = mocker.patch('app.template_previews.TemplatePreview.from_database_object')
     template = LetterPreviewTemplate(mock_get_service_letter_template(None, None)['data'])
 
-    ret = TemplatePreview.from_utils_template(template, 'foo')
+    ret = partial_call(template, 'foo')
 
     assert ret == mock_from_db.return_value
-    mock_from_db.assert_called_once_with(template._template, 'foo', template.values)
+    mock_from_db.assert_called_once_with(template._template, 'foo', template.values, page=expected_page_argument)
 
 
-def test_from_database_object_makes_request(mocker, client):
+@pytest.mark.parametrize('partial_call, expected_url', [
+    (
+        partial(TemplatePreview.from_database_object, filetype='bar'),
+        'http://localhost:6013/preview.bar',
+    ),
+    (
+        partial(TemplatePreview.from_database_object, filetype='baz'),
+        'http://localhost:6013/preview.baz',
+    ),
+    (
+        partial(TemplatePreview.from_database_object, filetype='bar', page=99),
+        'http://localhost:6013/preview.bar?page=99',
+    ),
+])
+def test_from_database_object_makes_request(
+    mocker,
+    client,
+    partial_call,
+    expected_url,
+):
     resp = Mock(content='a', status_code='b', headers={'c': 'd'})
     request_mock = mocker.patch('app.template_previews.requests.post', return_value=resp)
     mocker.patch('app.template_previews.current_service', __getitem__=Mock(return_value='123'))
 
-    ret = TemplatePreview.from_database_object(template='foo', filetype='bar')
+    ret = partial_call(template='foo')
 
     assert ret[0] == 'a'
     assert ret[1] == 'b'
     assert list(ret[2]) == [('c', 'd')]
-    url = 'http://localhost:6013/preview.bar'
+
     data = {
         'letter_contact_block': '123',
         'template': 'foo',
@@ -33,4 +64,4 @@ def test_from_database_object_makes_request(mocker, client):
     }
     headers = {'Authorization': 'Token my-secret-key'}
 
-    request_mock.assert_called_once_with(url, json=data, headers=headers)
+    request_mock.assert_called_once_with(expected_url, json=data, headers=headers)