Setup multiple git identities & git user informations

/!\ Be very carrefull in your setup : any misconfiguration make all the git config to fail silently !

Setup multiple git ssh identities for git

• Generate your SSH keys as per your git provider documentation.
• Add each public SSH keys to your git providers acounts.
• In your ~/.ssh/config, set each ssh key for each repository as in this exemple:

    Host github.com
    	HostName github.com
    	User git
    	IdentityFile ~/.ssh/github_private_key
    Host gitlab.com
    	Hostname gitlab.com
    	User git
    	IdentityFile ~/.ssh/gitlab_private_key

Setup dynamic git user mail & name depending on folder

/!\ Require git 2.13+ for conditionnal include support.

• In your ~/.gitconfig, remove the [user] block and add the following (adapt this exemple to your needs) :

    [includeIf "gitdir:~/code/personal/"]
    	path = .gitconfig-personal
    [includeIf "gitdir:~/code/professional/"]
    	path = .gitconfig-professional

• In your ~/.gitconfig-personal, add your personnal user informations:

    [user]
    	email = [email protected]     # note we use the noreply github mail
    	name = personal_username

• In your ~/.gitconfig-professional, add your professional user informations:

    [user]
    	email = [email protected]
    	name = professional_username

• Done !
• Now each repository will use custom user info depending on the top-level folder.