Move letter length check to utils repo so template-preview can use it, too

Update requirements

app/main/views/send.py

@@ -15,8 +15,9 @@ from flask import (
 )
 from flask_login import current_user
 from notifications_python_client.errors import HTTPError
-from notifications_utils import SMS_CHAR_COUNT_LIMIT
+from notifications_utils import LETTER_MAX_PAGE_COUNT, SMS_CHAR_COUNT_LIMIT
 from notifications_utils.columns import Columns
+from notifications_utils.pdf import is_letter_too_long
 from notifications_utils.recipients import (
     RecipientCSV,
     first_column_headings,
@@ -48,14 +49,12 @@ from app.s3_client.s3_csv_client import (
 )
 from app.template_previews import TemplatePreview, get_page_count_for_letter
 from app.utils import (
-    LETTER_MAX_PAGES,
     PermanentRedirect,
     Spreadsheet,
     email_or_sms_not_enabled,
     get_errors_for_csv,
     get_help_argument,
     get_template,
-    is_letter_too_long,
     should_skip_template_page,
     unicode_truncate,
     user_has_permissions,
@@ -596,7 +595,7 @@ def _check_messages(service_id, template_id, upload_id, preview_row, letters_as_
             service_id, template.id, db_template['version'], request.args.get('original_file_name', '')
         ),
         letter_too_long=is_letter_too_long(page_count),
-        letter_max_pages=LETTER_MAX_PAGES,
+        letter_max_pages=LETTER_MAX_PAGE_COUNT,
     )
 
 
@@ -890,7 +889,7 @@ def _check_notification(service_id, template_id, exception=None):
         back_link=back_link,
         help=get_help_argument(),
         letter_too_long=is_letter_too_long(page_count),
-        letter_max_pages=LETTER_MAX_PAGES,
+        letter_max_pages=LETTER_MAX_PAGE_COUNT,
         **(get_template_error_dict(exception) if exception else {}),
     )
 

app/main/views/templates.py

@@ -6,7 +6,9 @@ from flask import abort, flash, redirect, render_template, request, url_for
 from flask_login import current_user
 from markupsafe import Markup
 from notifications_python_client.errors import HTTPError
+from notifications_utils import LETTER_MAX_PAGE_COUNT
 from notifications_utils.formatters import nl2br
+from notifications_utils.pdf import is_letter_too_long
 from notifications_utils.recipients import first_column_headings
 
 from app import (
@@ -31,10 +33,8 @@ from app.models.service import Service
 from app.models.template_list import TemplateList, TemplateLists
 from app.template_previews import TemplatePreview, get_page_count_for_letter
 from app.utils import (
-    LETTER_MAX_PAGES,
     email_or_sms_not_enabled,
     get_template,
-    is_letter_too_long,
     should_skip_template_page,
     user_has_permissions,
     user_is_platform_admin,
@@ -77,7 +77,7 @@ def view_template(service_id, template_id):
         template_postage=template["postage"],
         user_has_template_permission=user_has_template_permission,
         letter_too_long=is_letter_too_long(get_page_count_for_letter(template)),
-        letter_max_pages=LETTER_MAX_PAGES,
+        letter_max_pages=LETTER_MAX_PAGE_COUNT,
     )
 
 

app/main/views/uploads.py

@@ -26,12 +26,7 @@ from app.s3_client.s3_letter_upload_client import (
     upload_letter_to_s3,
 )
 from app.template_previews import TemplatePreview, sanitise_letter
-from app.utils import (
-    LETTER_MAX_PAGES,
-    get_template,
-    is_letter_too_long,
-    user_has_permissions,
-)
+from app.utils import get_template, user_has_permissions
 
 MAX_FILE_UPLOAD_SIZE = 2 * 1024 * 1024  # 2MB
 
@@ -83,10 +78,7 @@ def upload_letter(service_id):
             else:
                 raise ex
         else:
-            if is_letter_too_long(page_count):
-                status = 'invalid'
-            else:
-                status = 'valid'
+            status = 'valid'
             file_contents = base64.b64decode(response.json()['file'].encode())
             upload_letter_to_s3(
                 file_contents,
@@ -117,7 +109,6 @@ def uploaded_letter_preview(service_id, file_id):
     metadata = get_letter_metadata(service_id, file_id)
     original_filename = metadata.get('filename')
     page_count = metadata.get('page_count')
-    letter_too_long = is_letter_too_long(int(page_count))
     status = metadata.get('status')
 
     template_dict = service_api_client.get_precompiled_template(service_id)
@@ -139,8 +130,6 @@ def uploaded_letter_preview(service_id, file_id):
         template=template,
         status=status,
         file_id=file_id,
-        letter_too_long=letter_too_long,
-        letter_max_pages=LETTER_MAX_PAGES,
     )