Store all data about uploaded letters in the S3 metadata

We had been storing whether or not a file was valid in the S3 metadata,
but using the query string of the URL to store the original filename
and the page count. This meant that if you tried to view the preview
letter page without the query string you would see a `500`. It was
possible for this to happen if you were signed out of Notify while on
the preview page - you would be redirected back to the preview page but
without the query string, causing an error.

tests/app/main/views/test_uploads.py

@@ -33,6 +33,8 @@ def test_post_upload_letter_redirects_for_valid_file(mocker, client_request):
         return_value=Mock(content='The sanitised content', json=lambda: {'file': 'VGhlIHNhbml0aXNlZCBjb250ZW50'})
     )
     mock_s3 = mocker.patch('app.main.views.uploads.upload_letter_to_s3')
+    mocker.patch('app.main.views.uploads.get_letter_metadata', return_value={
+        'filename': 'tests/test_pdf_files/one_page_pdf.pdf', 'page_count': '1', 'status': 'valid'})
     mocker.patch('app.main.views.uploads.service_api_client.get_precompiled_template')
 
     with open('tests/test_pdf_files/one_page_pdf.pdf', 'rb') as file:
@@ -46,14 +48,15 @@ def test_post_upload_letter_redirects_for_valid_file(mocker, client_request):
 
     mock_s3.assert_called_once_with(
         b'The sanitised content',
-        'service-{}/fake-uuid.pdf'.format(SERVICE_ONE_ID),
-        'valid',
+        file_location='service-{}/fake-uuid.pdf'.format(SERVICE_ONE_ID),
+        status='valid',
+        page_count=1,
+        filename='tests/test_pdf_files/one_page_pdf.pdf'
     )
 
     assert page.find('h1').text == 'tests/test_pdf_files/one_page_pdf.pdf'
     assert not page.find(id='validation-error-message')
 
-    assert page.find('input', {'type': 'hidden', 'name': 'filename', 'value': 'tests/test_pdf_files/one_page_pdf.pdf'})
     assert page.find('input', {'type': 'hidden', 'name': 'file_id', 'value': 'fake-uuid'})
     assert page.find('button', {'type': 'submit'}).text == 'Send 1 letter'
 
@@ -73,6 +76,8 @@ def test_post_upload_letter_shows_letter_preview_for_valid_file(mocker, client_r
     )
     mocker.patch('app.main.views.uploads.upload_letter_to_s3')
     mocker.patch('app.main.views.uploads.pdf_page_count', return_value=3)
+    mocker.patch('app.main.views.uploads.get_letter_metadata', return_value={
+        'filename': 'tests/test_pdf_files/one_page_pdf.pdf', 'page_count': '3', 'status': 'valid'})
     mocker.patch('app.main.views.uploads.service_api_client.get_precompiled_template', return_value=letter_template)
 
     with open('tests/test_pdf_files/one_page_pdf.pdf', 'rb') as file:
@@ -170,6 +175,8 @@ def test_post_upload_letter_with_invalid_file(mocker, client_request):
     mock_sanitise_response.raise_for_status.side_effect = RequestException(response=Mock(status_code=400))
     mocker.patch('app.main.views.uploads.sanitise_letter', return_value=mock_sanitise_response)
     mocker.patch('app.main.views.uploads.service_api_client.get_precompiled_template')
+    mocker.patch('app.main.views.uploads.get_letter_metadata', return_value={
+        'filename': 'tests/test_pdf_files/one_page_pdf.pdf', 'page_count': '1', 'status': 'invalid'})
 
     with open('tests/test_pdf_files/one_page_pdf.pdf', 'rb') as file:
         file_contents = file.read()
@@ -184,8 +191,10 @@ def test_post_upload_letter_with_invalid_file(mocker, client_request):
 
         mock_s3.assert_called_once_with(
             file_contents,
-            'service-{}/fake-uuid.pdf'.format(SERVICE_ONE_ID),
-            'invalid',
+            file_location='service-{}/fake-uuid.pdf'.format(SERVICE_ONE_ID),
+            status='invalid',
+            page_count=1,
+            filename='tests/test_pdf_files/one_page_pdf.pdf'
         )
 
     assert page.find('h1').text == 'tests/test_pdf_files/one_page_pdf.pdf'
@@ -209,6 +218,8 @@ def test_post_upload_letter_shows_letter_preview_for_invalid_file(mocker, client
     mock_sanitise_response.raise_for_status.side_effect = RequestException(response=Mock(status_code=400))
     mocker.patch('app.main.views.uploads.sanitise_letter', return_value=mock_sanitise_response)
     mocker.patch('app.main.views.uploads.service_api_client.get_precompiled_template', return_value=letter_template)
+    mocker.patch('app.main.views.uploads.get_letter_metadata', return_value={
+        'filename': 'tests/test_pdf_files/one_page_pdf.pdf', 'page_count': '1', 'status': 'invalid'})
 
     with open('tests/test_pdf_files/one_page_pdf.pdf', 'rb') as file:
         page = client_request.post(
@@ -253,6 +264,8 @@ def test_post_upload_letter_does_not_upload_to_s3_if_template_preview_raises_unk
 
 def test_uploaded_letter_preview(mocker, client_request):
     mocker.patch('app.main.views.uploads.service_api_client')
+    mocker.patch('app.main.views.uploads.get_letter_metadata', return_value={
+        'filename': 'my_letter.pdf', 'page_count': '1', 'status': 'valid'})
 
     page = client_request.get(
         'main.uploaded_letter_preview',
@@ -268,8 +281,11 @@ def test_uploaded_letter_preview(mocker, client_request):
 
 
 def test_send_uploaded_letter_sends_letter_and_redirects_to_notification_page(mocker, service_one, client_request):
-    mocker.patch('app.main.views.uploads.get_letter_pdf_and_metadata', return_value=('file', {'status': 'valid'}))
+    metadata = {'filename': 'my_file.pdf', 'page_count': '1', 'status': 'valid'}
+
+    mocker.patch('app.main.views.uploads.get_letter_pdf_and_metadata', return_value=('file', metadata))
     mock_send = mocker.patch('app.main.views.uploads.notification_api_client.send_precompiled_letter')
+    mocker.patch('app.main.views.uploads.get_letter_metadata', return_value=metadata)
 
     service_one['permissions'] = ['letter', 'upload_letters']
     file_id = 'abcd-1234'
@@ -315,8 +331,11 @@ def test_send_uploaded_letter_when_service_does_not_have_correct_permissions(
 
 
 def test_send_uploaded_letter_when_metadata_states_pdf_is_invalid(mocker, service_one, client_request):
-    mocker.patch('app.main.views.uploads.get_letter_pdf_and_metadata', return_value=('file', {'status': 'invalid'}))
     mock_send = mocker.patch('app.main.views.uploads.notification_api_client.send_precompiled_letter')
+    mocker.patch(
+        'app.main.views.uploads.get_letter_metadata',
+        return_value={'filename': 'my_file.pdf', 'page_count': '3', 'status': 'invalid'}
+    )
 
     service_one['permissions'] = ['letter', 'upload_letters']
     file_id = 'abcd-1234'

tests/app/s3_client/test_s3_letter_upload_client.py

@@ -6,12 +6,17 @@ from app.s3_client.s3_letter_upload_client import upload_letter_to_s3
 def test_upload_letter_to_s3(mocker):
     s3_mock = mocker.patch('app.s3_client.s3_letter_upload_client.utils_s3upload')
 
-    upload_letter_to_s3('pdf_data', 'service_id/upload_id.pdf', 'valid')
+    upload_letter_to_s3(
+        'pdf_data',
+        file_location='service_id/upload_id.pdf',
+        status='valid',
+        page_count=3,
+        filename='my_doc')
 
     s3_mock.assert_called_once_with(
         bucket_name=current_app.config['TRANSIENT_UPLOADED_LETTERS'],
         file_location='service_id/upload_id.pdf',
         filedata='pdf_data',
-        metadata={'status': 'valid'},
+        metadata={'status': 'valid', 'page_count': '3', 'filename': 'my_doc'},
         region=current_app.config['AWS_REGION']
     )