Don’t strip HTML when saving templates

Right now we strip HTML from templates at the point of saving them. This
also converts stuff like ampersands to their entity form (eg &) and
this is what we save in the database.

This is a bad idea when you’re sending a text message or a letter, in
which an HTML entity makes no sense. But we still need to encode HTML in
the body of HTML emails.

The right place to do this is when rendering the templates. The code to
do this is now in utils. So this commit:
- pull in this new utils code
- removes the old
- adds some integration tests to make sure that everything is working
  as expected (more thorough unit tests are happening in utils)

app/template/rest.py

@@ -4,7 +4,6 @@ from flask import (
     request,
     current_app
 )
-import bleach
 
 from app.dao.templates_dao import (
     dao_update_template,
@@ -41,7 +40,6 @@ def create_template(service_id):
     fetched_service = dao_fetch_service_by_id(service_id=service_id)
     new_template = template_schema.load(request.get_json()).data
     new_template.service = fetched_service
-    new_template.content = _strip_html(new_template.content)
     over_limit = _content_count_greater_than_limit(new_template.content, new_template.template_type)
     if over_limit:
         char_count_limit = current_app.config.get('SMS_CHAR_COUNT_LIMIT')
@@ -60,7 +58,6 @@ def update_template(service_id, template_id):
     current_data = dict(template_schema.dump(fetched_template).data.items())
     updated_template = dict(template_schema.dump(fetched_template).data.items())
     updated_template.update(request.get_json())
-    updated_template['content'] = _strip_html(updated_template['content'])
     # Check if there is a change to make.
     if _template_has_not_changed(current_data, updated_template):
         return jsonify(data=updated_template), 200
@@ -137,10 +134,6 @@ def get_template_versions(service_id, template_id):
     return jsonify(data=data)
 
 
-def _strip_html(content):
-    return bleach.clean(content, tags=[], strip=True)
-
-
 def _template_has_not_changed(current_data, updated_template):
     return all(
         current_data[key] == updated_template[key]