title: Caching your GitHub credentials output: html_document: toc: true

toc_depth: 4

Why do we want to cache credentials?

You need to get Git to remember your GitHub username and password, so that every time you push, you do NOT have to authenticate yourself interactively.

You only have to set this up once every couple of months or once per computer.

You will know you have truly succeeded once you have at least one successful push to GitHub in which you are NOT challenged for your user name and password.

Get a test repository

You need a functioning test Git repository. One that exists locally and remotely on GitHub, with the local repo tracking the remote.

If you have just verified that you can interact with GitHub from your local computer, that test repo will be perfect.

If you are testing that you can work with GitHub from RStudio, that test repo will be perfect.

You may proceed when

  • You have a test repo.
  • You know where it lives on your local computer. Example:
    • /home/jenny/tmp/myrepo
  • You know where it lives on GitHub. Example:
    • https://github.com/jennybc/myrepo

  • You know local is tracking remote. In a shell with working directory set to the local Git repo, enter these commands:

    jenny@2015-mbp myrepo $ git remote -v
origin    https://github.com/jennybc/myrepo (fetch)
origin    https://github.com/jennybc/myrepo (push)

jenny@2015-mbp myrepo $ git branch -vv
* master b8e03e3 [origin/master] line added locally

We want to see that fetch and push are set to remote URLs that point to your GitHub repo. We also want to see that your local master branch has your GitHub master branch as upstream remote. Gibberish? Just check that your output looks similar to mine.

Verify that your Git is new enough to have a credential helper

In a shell, enter git --version and verify that you have 1.7.10 or newer. If you don't, update Git.

Turn on the credential helper

Windows

In the shell, enter git config --global credential.helper wincred

Windows, plan B

If that doesn't seem to work, install an external credential helper.

  • Download the git-credential-winstore.exe application.

  • Run it! It should work if Git is in your PATH environment variable. If not, go to the directory where you downloaded the application and run the following: git-credential-winstore -i "C:\Program Files (x86)\Git\bin\git.exe"

Mac

Find out if the credential helper is already installed. In the shell, enter git credential-osxkeychain. You should see something like this: Usage: git credential-osxkeychain <get|store|erase>. If you do not, follow steps 2 and 3 on the github help.

Once you've confirmed you have the credential helper, enter git config --global credential.helper osxkeychain

Linux

In the shell, enter git config --global credential.helper 'cache --timeout=10000000' to store your password for ten million seconds (that's 16 weeks, enough for a full term).

Trigger a username / password challenge

Change a file in your local repo and commit it. Do that however you wish. Here are shell commands that will work:

echo "adding a line" >> README.md
git add -A
git commit -m "A commit from my local computer"

Now push!

git push -u origin master

One last time you will be asked for your username and password, which hopefully will be cached.

Now push AGAIN.

git push

You should NOT be asked for your username and password, instead you should see Everything up-to-date.

Rejoice and close the shell. From now on your "Push" button in RStudio will just work.

More options

  • Above we are connecting to GitHub via HTTPS. The alternative is SSH. We follow GitHub's advice, which is to prefer HTTPS over SSH, but both are perfectly valid.

Go back to the index for the all the Git stuff.