How to get website metrics from Google Analytics with Flask Python

If you don’t know what Google Analytics does, it is a powerful tool created by Google which uses some scripts to determine all sorts of information about the users accessing your app. This app can be a website, mobile app, script or others that can track information such as location, the number of page loads, browser type, device type etc.

I’m going to show you how to retrieve those metrics from Google Analytics into your Flask app. The purpose of this task would be if you would like to process this data even further or just to display it on your app by making a custom interface/admin panel.

Steps

1. Creating a simple Flask app

(You can skip this step if you’re implementing it on a website you’ve already made)

Create a main.py file with the basic flask structure
Create a virtual environment and install the requirements
pip freeze the requirements into a text file
Upload your files to a hosting provider

2. Creating a Google Analytics property

(You can skip this step if you had already done this.)

Go to here > Admin > Create property
Give it a suggestive name and fill in the other requested information about your app, click on advanced options and toggle “Create a Universal Analytics property”, input the URL and select “Create a Universal Analytics property only”

3. Link the Google Analytics property to your website

From the “Tracking Info” > “Tracking Code” section of the property copy the “Global Site Tag (gtag.js)” script
Place the script in the head of your html file (place it in layout.html if you want tracking across every page)
Upload the changes to the server
Make sure the Realtime Users are updating when you access your website.

! Keep in mind that it will take longer for the analytics for the past few days to show up

4. Set up the Analytics Reporting API on Google Cloud Platform

Open the GCP Console
On Home > Dashboard click on Create project and give it a suggestive name
Go to APIs & Services > Library, search for “Google Analytics Reporting API” and click on Enable
Open the Service page, select your project, click on Create service account and input a name and a description(the next two steps are not needed)
After you created your service account click the three dots icon then Manage keys
Click on Add Key and select JSON(a JSON file will be downloaded)
Place the downloaded file into your python project

5. Add the GCP Service Account to the Google Analytics account

From the previously downloaded JSON file copy the “client email” field (it should look something like this serviceaccount@gcpprojectid.iam.gserviceaccount.com)
On the Google Analytics > Admin page > View User Management(under the view section) click on the “+” button and Add user. Paste the email address that you copied and make sure “Read & Analyze” is checked

6. Retrieve the data from the API using python and Flask

Make sure that you are running the python app in virtual environment.

Install the necessary libraries inside the virtual environment and add them to the requirements file

pip install google-api-python-client
pip install oauth2client
pip freeze > requirements.txt

Flask app that retrieves the number of visitors from the past 30 days and displays them on a page.
Replace KEY_FILE_LOCATION with the name of the JSON file we downloaded previously and VIEW_ID with the one found in Admin > Property > View > View settings. The function get_visitors() can be changed to get other types of metrics such as browser type, country or others. You can find more info about this in the Google Analytics Response API documentation

A basic structure of layout.html

<!DOCTYPE html>
<html>
    <head>
         <title>Visitors</title>
    </head>
    <body>
         <h1>The number of visitors from the past 30 days: <span style="color: Cyan">{{ visitors }}</span></h1>
    </body>
</html>