How to have branch specific variables in GIT and python

Question

I have 2 different branches, master and test. Those branches are exact replicas except for the database string which is different for master and test. Everytime I merge test to master, the database string in the master gets replaced by the test database string.

I have heard about using branch specific variables, so I don't need to worry about the database string getting changes on merge as .env variables will take care of it.

Please let me know how do I do that.

Where are your environment variables stored? You should be able to have separate files to store the environment variables for each branch. — adamgy, Jul 10 '20 at 20:01
This sounds like you don't need separate branches, but could read the database string from some environment specific configuration. This would avoid any merge problems. — MrBean Bremen, Jul 10 '20 at 21:06
How to I make env files and access thier value in code? Can you provide with an example? — Farhaan Patel, Jul 10 '20 at 21:14
`python-dotenv` is great for automatically setting env variables with a .env file. — Merlin, Jan 11 '23 at 01:04

score 1 · Accepted Answer · answered Jul 11 '20 at 02:40

as .env variables will take care of it.

You could generate the right .env file.
And rename the current .env into .env.master and .env.test

In each branch, you would then generate .env, with the right content in it, from one of those files, depending on the current execution environment.

The generation script will determine the name of the checked out branch with:

branch=$(git rev-parse --symbolic --abbrev-ref HEAD)

Finally, you would register (in a .gitattributes declaration) a content filter driver.

^{(image from "Customizing Git - Git Attributes", from "Pro Git book")}

The smudge script, associated the .env.branch file, would generate (automatically, on git checkout or git switch) the actual .env file by looking values in the right .env.branch value file.
The generated actual .env file remains ignored (by the .gitignore).

See a complete example at "git smudge/clean filter between branches".

How to have branch specific variables in GIT and python

1 Answers1