🔖 Added article on git remote add set-url

Author: Bernard `Guyzmo` Pratz

content/code/on/git:_how_to_setup_one_remote_with_multiple_url.markdown

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+---
+type: post
+categories: code
+tags: [ code, python, tip, git ]
+title: "A tip for git, discover multiple URL remote"
+date: 2016-12-30T20:28:42+02:00
+summary: "While I was developing git-repo I stumbled upon a little known feature that
+has been introduced in git 2.7: the possibility to have a remote with multiple
+URLs. After the break I'll tell you what this is about…"
+lang: english
+logo: /img/gitlogo-black.png 
+header_background: /img/gitdark-bg.png 
+tweet: 814917694436868097
+aliases: /code/on/git:_how_to_setup_one_url_with_multiple_remotes
+---
+
+While I was developing [git-repo] I stumbled upon a little known feature that
+has been introduced in git 2.7: the possibility to have a remote with multiple
+URLs.
+
+# Why would I need that?
+
+What's great with git is that it's a decentralized version control system. What that
+means is that, even if most of the time you'll work with only one remote repository (in a
+very centralised way), sometimes you'll be happy to be able to have many remotes to
+work with.
+
+An use case I had in a former work setup was to have an internal repository (that will
+feature the open code, as well as some custom features in branches for our paying customers),
+an external repository (because opensource is ♥), a production repository (for deployment
+purposes, but it's not anymore a use case thanks to CI integrations that [does automatic
+deployment](https://about.gitlab.com/gitlab-ci/)).
+
+Another use case, which was the one I ran into when developing [git-repo], is working
+with several repository services at once. You've got gitlab, github, bitbucket, gogs…
+And when you're working with all of them you got to create a remote for each, and
+push your changesets to each of them everytime:
+
+``` bash
+git remote add github https://github.com/guyzmo/git-repo
+git remote add gitlab https://gitlab.com/guyzmo/git-repo
+git remote add bitbucket https://bitbucket.org/guyzmo/git-repo
+git remote add home https://gitlab.myserver.com/guyzmo/git-repo
+git remote add gogs https://gogs.myserver.com/guyzmo/git-repo
+```
+
+it's a bit boring and redundant to do so, but at least that's a task you do only
+once (and you can do it faster with [a great editor](http://vim.org) on the `.git/config` file).
+
+But each time you want to push to your projects, you got to push to each of them:
+
+``` bash
+git push github master
+git push gitlab master
+git push bitbucket master
+git push home master
+git push gogs master
+```
+
+And as you're as lazy as anybody, you'll end up only pushing to one, maybe two
+of the remotes, usually `github` and `home`…
+
+# The multiple URL remote comes to help
+
+…But you don't really have to! You can work with multiple remotes nicely, by creating
+a new remote that contains all the other remotes URLs:
+
+``` bash
+git remote add all https://github.com/guyzmo/git-repo
+git remote add all set-url --add https://gitlab.com/guyzmo/git-repo
+git remote add all set-url --add https://bitbucket.org/guyzmo/git-repo
+git remote add all set-url --add https://gitlab.myserver.com/guyzmo/git-repo
+git remote add all set-url --add https://gogs.myserver.com/guyzmo/git-repo
+```
+
+then, when it's time to push your code, you just need to run:
+
+``` bash
+git push all master
+```
+
+The only drawback is that it makes little sense to pull from a remote with multiple URL,
+and when looking at your index, you'll see that the `all/master` ref is updated, but
+not the other refs (`github/master`, `gitlab/master`…). So if you want to keep all the
+remotes updated you've got to run:
+
+``` bash
+git fetch --all
+```
+
+which will sync back all the refs that have been updated when you pushed through the all
+remote. So instead of 4/5 or more commands to repeat, you end up with only two commands.
+
+And you can make it simpler using an alias such as:
+
+``` bash
+git config alias.pushall "!pushall() { git push all $* && git fetch --all ; }; pushall"
+```
+
+# And how is it being used in [git-repo]?
+
+When I worked on [git-repo], I figured that's a great feature to take advantage of. So
+I've implemented a customized version of the `git remote add`, that's being used under
+the hood by `git <target> create`, `git <target> clone`, git <target> fork`…
+
+This is the `git <target> add` command, and it works as follows:
+
+``` bash
+git hub add <user>/<repo> [<name>] [--tracking=<branch>] [-a]
+```
+
+there you can add to the list of remotes the repository as identified by the repo slug
+(`<user>/<repo>`, a full URL to the repo works as well, as long as it matches the targetted
+service provider). Then you can give a custom name to the repo and specify the branch you
+want to track (with `--tracking`). The `-a/--alone` parameter is to prevent from adding
+the URL to the `all` remote.
+
+``` bash
+% git hub add foobar/project foobar --tracking=devel
+Successfully added `foobar/project` as remote named `foobar`
+% git remote
+all
+foobar
+github
+% git remote get-url --all all
+git@github.com:guyzmo/clait
+git@github.com:foobar/project
+```
+
+As a nice to have idea I'd like to implement would be to make the `add` command so it is possible
+to handle `remote add` with just any repository, something that's like:
+
+``` bash
+% git <target> add user@10.0.0.1:./repository.git local_machine --tracking=devel
+Successfully added `user@10.0.0.1:./repository.git` as remote named `local_machine`
+```
+
+At the time of writing this article, the feature [has been implemented](https://github.com/guyzmo/git-repo/compare/devel...features/repo_add_cmd?expand=1),
+and will be merged to one of the future versions of [git-repo].
+
+[git-repo]:https://github.com/guyzmo/git-repo