2-5-HowToUseGitIgnore.txt

2-4 How to Use a .gitignore

Ok so let's say there's a file that you need locally and you don't want it in remote

This happens pretty often, actually!

There are some filetypes that really shouldn't be in a repo
like video - it's too big!
so that's one reason you might use a .gitignore

You'll remember too that for free accounts, your repos are public
that means that every line of code in there is accessible by anyone with an internet connection

There are lots of programming tasks that require passwords, though
if you're using an API for anything, for example
you usually have to send some kind of token/ key to the service with your API calls
Or, if you're sending an email with your script
you need to authenticate to the email server

You don't want those passwords on the open web!

the way to deal with that is:
locally, you have a file named something like: credentials_all.txt
that file stores all your passwords and API access tokens
your script parses it when it needs to use a password for something

that file is then added to the .gitignore

and it never ends up in the remote repo
it also means that changes to this file aren't tracked!
but, you manage this file manually, so that's ok usually

As always, I'm following the official GitHub documentation for this, available here:
https://docs.github.com/en/github/authenticating-to-github/connecting-to-github-with-ssh

additionally, I'm using a flavor of Arch Linux
so the exact commands may or may not be suitable for your Windows or Mac environment
but the doc linked above has you covered

1. how to create a .gitignore file
go to your repository's local folder in your file browser
click "show hidden files"
go into the .git folder in terminal
in terminal, type: touch .gitignore
or, in your favorite text editor: open a new file and save as .gitignore

in this .gitgnore file, type: credentials_all.txt

add, commit, and push your changes
you should see that everything but credentials_all.txt is in your remote repo


2. how to add a class of files to .gitignore
.gitignore supports wildcards!
I mentioned before that you generally don't want video in your repos
to exclude all .mov files from your repo you would type: *.mov
and you can do that for any filetype

or you can exclude files in a folder with: dont_push_me/
that's a relative path to the main repo directory
so to exclude just a subdirectory you can use: really/dont_push_me


3. how to remove a file that's already been tracked
But Brendan, you're saying,
"I already pushed my password to remote, what can I do?"
and that's a good question!

you'll recall that git saves the changes, so if you just re-do the code and delete your password
it's still available in an older commit, so people can still access it

let's remove it for good!

first, if you made a rule for it in .gitignore, you gotta remove the rule
if you committed your changes, you gotta undo them

once the rule is gone,
in terminal, type: git rm --cached credentials_all.txt

add and commit your changes
re-add the rule
add and commit those changes
and push everything to remote

that file should be gone forever