I implemented a continuous integration pipeline using Jenkins, but as final step I want Jenkins to deploy/upload the signed APK file to Google Play Store and AndroidPit. I l
First go to Google Play Console in a browser, open the page for your app, and look for the option to allow a new email address to upload APKs. If it's not there, it probably means you are not the administrator of that Play Store account and you need to ask the person who is the administrator to add it for you (on a per-app basis). To find out what email address to add, go to Google Developer Service Accounts and create a JSON key for any of your existing Google developer service accounts, or create a new service account with a JSON key. Note the email address associated with the service account for which you have created (or will create) the JSON key. It will most likely be something at gserviceaccount.com. This is the email address that must be given permission to upload APKs by someone who has admin access to your Play account.
After that has been done, download Madison Dickson's updated version of Marta Rodriguez's script via wget https://gist.githubusercontent.com/mix3d/665f4ab329b4482297a2f425ebba402c/raw/0949385dd6c80d0701170746b1bd5fd479303412/basic_upload_apks_service_account.py and install dependencies via pip install google-api-python-client (or sudo pip install google-api-python-client as appropriate).
Then in the automated script you can use (for example) python basic_upload_apks_service_account.py -t beta -p org.example.MyApp -s JSON_file_I_made.json -a MyApp.apk (assuming your JSON file, your APK, and basic_upload_apks_service_account.py are all in the current directory and the pip install has been done on that machine or container).
I strongly recommend uploading to beta (hence -t beta in the above) rather than directly to production. Just in case something breaks and it somehow gets as far as the APK upload. I think the final press of "rollout to production" should always be done by a human. But if you really want to do that automatically as well, you can use -t production instead.