How to automate Github using Cron?

Leverage crontab utility for running sequence of Github commands regularly.

Use Case : Keeping my fork* updated with the upstream*

Technology used : Bash Scripting, Git, SSH, Cron

Initial setup

cd /home/ubuntu
mkdir src && cd src/
git clone --recursive git@github.com:ChaiBapchya/incubator-mxnet.git

Note : Use ssh link instead of https for git clone

SSH vs HTTPS git clone

In order to automate git commands using bash script, we should use SSH over HTTPS. Using SSH is a safer way of providing authentication & permissions to perform git commands.

Setup SSH keys on Github account & machine

First, generate a new SSH key [pair of public and private keys]

Verify the SSH key is correct

$ ssh -T git@github.com
Hi ChaiBapchya! You’ve successfully authenticated, but GitHub does not provide shell access.

Copy the public key

$ cat ~/src/id_rsa.pub

Upload it to Github account following steps mentioned here.

For my use-case, I want to sync my fork & rebase the feature branch.
In order to sync with the upstream, I have to add the upstream repository once. Moreover, to update the feature-branch I need to fetch it once. The name of my feature branch is update_gpu_toolchain

cd incubator-mxnet/
git remote add upstream https://github.com/apache/incubator-mxnet
git fetch origin
git checkout --track origin/update_gpu_toolchain
cd ..

Bash Script

vi cron_rebase_gpu.sh