Flask: How to prevent Google Analytics JS to run in dev environment?

Question

When signing up with google analytics there is a piece of js script that needs to be inserted in the base.html

<script>
      (function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){
      (i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new Date();a=s.createElement(o),
      m=s.getElementsByTagName(o)[0];a.async=1;a.src=g;m.parentNode.insertBefore(a,m)
      })(window,document,'script','//www.google-analytics.com/analytics.js','ga');

      ga('create', 'xxx', 'example.com');
      ga('send', 'pageview');

    </script>

Problem with having it always there is, that development machines would submit unnecessary data that is not from real users. I was wondering if there is a way to ask if flask is in the debug mode, and hence do not load this script in first place.

How can I check for debug mode in the template?

Answer 1

If you are not using it already you should create one file called config.py and then load it into your Flask app, by doing something like this:

import config
app = flask.Flask(__name__)
app.config.from_object(config)

Then in the config.py file you can write:

# Running on App Enginge
PRODUCTION = os.environ.get('SERVER_SOFTWARE', '').startswith('Google App Engine') 
# Running Localy
DEVELOPMENT = not PRODUCTION
# You decide when is DEBUG mode, usually when running locally
DEBUG = DEVELOPMENT

And then in your template you can use these values like this:

{% if not config.DEBUG %}
  <script>
    ...
  </script>
{% endif %}

You could also exclude the admin users of your application to affect the analytics since they are most likely going to abuse them anyway. If you implemented the current_user the Flask way then your template should be change to:

{% if not current_user.admin and not config.DEBUG %}
  <script>
    ...
  </script>
{% endif %}

Among other things, all of the above (config.py, main.py, analytics.html) above are used in my gae-init project.