Git

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Revision as of 23:25, 23 February 2016 by Rambala (talk | contribs) (Updating from the main repository (pull))

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How to use git with the papaprazzi master repo.

The RepositoryStructure page explains the various branches. Most users probably want the latest stable branch (currently v5.6). The master branch is for active development.

Git help and resources

There are tons of tutorials, etc. out there... first check out the git documentation.

FixIt

You can also get help on any Git command by doing git command -h or git help command.

Never used git before? Read (and watch) learn.github.com/p/intro.html.

To get an understanding off the git internals the "Getting Git" video by Scott Chacon is excellent.

More:

Before You Start

Git is not an evolution of SVN (like SVN is from CVS). This may lead to a lot of extra head scratching among migrates. You have been warned.

Basic Git configuration

First tell git your real name and your e-mail address. You should add these before you start using Git:

git config --global user.name "Your Name"
git config --global user.email you@yourdomain.example.com

There is a nice guide of how to set up git for use with github.

Get the code

If you plan to contribute or just to push your own config to github please use Option 1 to create your own account and fork the papaprazzi repo.

Otherwise use Option 2 to directly get the code.


Option 1: Fork paparazzi to your own github repo and clone from there

Set up a Github account

If you want some github awesomeness you have to create an account there and set up git. Do not forget to provide your ssh key and github token, otherwise you will not be able to access your repositories.

Fork paparazzi and clone your new repo

To fork paparazzi, just log in to github, go to the main papaprazzi software repository and click fork at the top of the page. This created the new paparazzi repository on your own github account which you can now clone to your local machine.

When you initially clone a repo to your local machine git gives this remote repo the name origin.

git clone git@github.com:<your github username>/paparazzi.git

Optionally you can give your remote a more descriptive name when cloning by adding the option -o:

git clone -o <name> git@github.com:<your github username>/paparazzi.git

The option -o <name> uses name to keep track of the repository instead of using the remote name origin. You can name the remote for your own paparazzi fork according you your username and the paparazzi master repo upstream to avoid confusion.

Adding remotes

Now you want to add the main repo as a remote with the name upstream to easily pull changes from there:

git remote add upstream git://github.com/paparazzi/paparazzi.git

The above URL provides read-only access, if you are a dev and have write access to the main repo as well you want to use:

git remote add upstream git@github.com:paparazzi/paparazzi.git

Option 2: Directly clone paparazzi without a github account

Clone directly from the master repo (read-only):

git clone git://github.com/paparazzi/paparazzi.git

or if you are behind a firewall with an http proxy available:

git clone https://github.com/paparazzi/paparazzi.git

This will name the remote Paparazzi repository origin. You can add the option -o name to use name (e.g. upstream) to keep track of the paparazzi master repo to avoid confusion.

git clone -o upstream git://github.com/paparazzi/paparazzi.git

Basic git usage

See what's going on

To show the status (modified and staged changes) you can run

git status

To list your branches and the corresponding upstream branch (the one marked with the star is the currently used branch):

git branch -vv

Gitk is your friend if you want to visualize all remotes/branches and history:

gitk --all

Updating from the main repository (pull)

Have a look at the very good short overview of pushing and pulling on gitready.com and the syncing a fork article on github.

To fetch the changes from the stable branch (e.g. currently v5.8) on github and merge them into your local branch run

git pull <remote> v5.8

Where <remote> is the name for the remote to the main Paparazzi repo and is usually upstream or origin depending on your earlier setup.

If you want to use the latest bleeding edge version, checkout out the master (development) branch:

git checkout master

To update it:

git pull upstream master

Publishing your changes

To push your (already locally committed) changes to your own github master branch

git push <remote> <branch>

Where <remote> is the name for the remote to your own github repo and is usually origin or your username (depending on your earlier setup).<br\> And <branch> is the branch you want to push to your remote repository, either master or your topic branch.

Contribute

If you are working on a new feature, you should do all your work in a topic branch which then can be merged back into master when it is ready. If you are just working on a small fix for a specific release, you can do that from the branch for the respective version. Please send us a pull request on github.

I you want to update your branch it is good practice (in most cases) to use git up (git pull --rebase) instead of git pull (See below to define git up as an alias for git pull --rebase). This will rebase your changes ontop of the current master instead of merging. It is very useful to keep the history more readable and make bug searching easier.


So the basic pattern looks something like this:

  1. Fetch the latest versions from the main repo: git fetch or git remote update to update all remotes
  2. Create a new branch of the current master branch:
    git checkout -b new_feature upstream/master
  3. Add and commit changes to the new branch (with a good commit message)
  4. Rebase updates from upstream branch:
    git up upstream/master
  5. Push it to the repo when it is ready
  6. send us a pull request

Advanced Configuration and helpful tools

If you want to inspect your global configuration, have a look at the .gitconfig file in your home directory.

The per repository configuration is stored in the .git/config file in your repository.

Colors and Aliases

You also might want to set some color options and aliases, e.g.:

git config --global color.ui auto     # colors for all
git config --global alias.st status   # make `git st` work
git config --global alias.co checkout # make `git co` work
git config --global alias.ci commit   # make `git ci` work
git config --global alias.br branch   # make `git br` work
git config --global alias.up "pull --rebase"   # make `git up` work similar to svn up
git config --global alias.lg "log --graph --pretty=format:'%Cred%h%Creset -%C(yellow)%d%Creset %s %Cgreen(%cr) %C(bold blue)<%an>%Creset' --abbrev-commit --date=relative"

Line endings

Although you might think you’re immune to CRLF-ended files on mac and linux, you are not. It is possible to download files from an external source that use CRLF, and thus commit them into your repo. You should globally set your config to convert line endings on commit so they are always LF in the repo (or omit the --global for paparazzi only):

git config --global core.autocrlf input

If you are on a windows box by any chance set:

git config --global core.autocrlf true

Magit

If you are an emacs user you might want to have a look at http://philjackson.github.com/magit/

git status in shell

For bash: http://www.gitready.com/advanced/2009/01/23/bash-git-status.html

For zsh: http://www.wunjo.org/zsh-git/