Handling Multiple Github Accounts on MacOS

The only way I've succeeded so far is to employ SSH.

Assuming you are new to this like me, first I'd like to share with you that your Mac has a SSH config file in a .ssh directory. The config file is where you draw relations of your SSH keys to each GitHub (or Bitbucket) account, and all your SSH keys generated are saved into .ssh directory by default. You can navigate to it by running cd ~/.ssh within your terminal, open the config file with any editor, and it should look something like this:

Host *
 AddKeysToAgent yes
 UseKeyChain yes
 IdentityFile ~/.ssh/id_rsa
 ForwardAgent yes

Assuming you've got 2 github accounts, for work and play, lets get your Mac to "register" them. To do that that you'll need to create SSH key pairs for each account. If you have already setup your Mac to SSH with one of them, or check if you have one, continue on with the following for the second account.

1. Creating the SSH keys. For each SSH key pairs:

run ssh-keygen -t rsa -b 4096 -C "[email protected]"
You'll be prompted: "Enter a file in which to save the key" and the suggested default filename would be id_rsa. This filename will be used for your SSH private and public keys so remember to make it unique, eg. user-1, user-2. This step will generate both the private and public keys, user-1 + user-1.pub , user-2 + user-2.pub respectively.
GitHub has this step in detail. We're not adding the keys to the ssh-agent.

2. Register your keys to the respective GitHub accounts.

Follow these steps to do so.

3. Head back over to the SSH `config` file at `~/.ssh` and amend accordingly to:

#user1 account
Host github.com-user1
   HostName github.com
   User git
   IdentityFile ~/.ssh/github-user1
   IdentitiesOnly yes

#user2 account
Host github.com-user2
   HostName github.com
   User git
   IdentityFile ~/.ssh/github-user2
   IdentitiesOnly yes

Replace user1 or user2 with your GitHub usernames/identification-handlers

4. Go ahead to git clone your respective repository

git clone [email protected]:user1/your-repo-name.git your-repo-name_user1

5. Configure your git identity:

Open up local git config using git config --local -e and add:

[user]
    name = user1
    email = [email protected]

6. Ensure your remote url is in the right format e.g: `[email protected]:user1/your-repo-name.git your-repo-name_user1`

You either run git remote set-url origin [email protected]:user1/your-repo-name.git your-repo-name_user1
Or amend your remote ssh-url in your local git config file:

 [remote "origin"] 
       url = [email protected]:user1/your-repo-name.git
       fetch = +refs/heads/*:refs/remotes/origin/*

Now you can git actions (pull/push/fetch...etc) all you like!

Resources:

Special thanks to @pbuditi for your help!

primayudantra/handling_multiple_github_accounts.md