Ry's Git Tutorial - 2

Remotes

clone

使用git clone将本地的my-git-repo复制成marys-repo

cd /path/to/my-git-repo
cd ..
git clone my-git-repo marys-repo
cd marys-repo

配置本地仓库, 让别人知道写代码的是谁(git log时能看到author)

git config user.name "Mary"
git config user.email mary.example@rypress.com

查看本地仓库配置 **cat .git/config**
查看全局配置 **cat ~/.gitconfig**

Just as branches are anabstraction for the working directory, the staged snapshot, and a commit history, a repository is an abstraction for branches.

在marys-repo执行命令git remote查看远程仓库, 可以看到有个origin
加上-v (verbose)参数可以查看详情
可以看到marys-repo的远程仓库就是my-git-repo
这是因为marys-repo是git clone得来的

注意: marys-repo和my-git-repo是两个相互独立的库

回到my-git-repo
git remote查看不到远程仓库
**git remote add mary ../marys-repo** 将marys-repo添加为远程仓库
git remote add <remote-name> <remote-path>

现在2个库都互为远程仓库

fetch

使用**git branch -r** 查看远程分支(remote branches)
**git fetch mary** Download remote branch information, but do not merge anything.
This will go to the “fetch” location shown in git remote -v and download all of the branches it finds there into our repository.

远程分支仅仅是拷贝到我们仓库的副本,所以不是实时更新的,每次都要手动fetch

Check Out a Remote Branch

git checkout mary/master 切换到mary的分支查看她做了什么更改, 此时是处于detached HEAD状态
git log master..mary/master --stat
git log mary/master..master --stat 查看两个分支的异同

Merge Mary’s Changes

git checkout master
git merge mary/master 将mary的分支合并到我们的分支
此时mary的commit变成了我们master分支的一部分

Push a Dummy Branch

fetching imports remote branches, while pushing exports local branches to another repository
git branch dummy
git push mary dummy
创建dummy分支,把它push给远程仓库mary
在marys-repo查看分支 git branch, 可以看到dummy分支

给别人的仓库push分支会制造混乱, 如果那个分支不存在,就会凭空多出一个分支, 所以永远不要这么做! you should never push into another developer’s repository.

Push a New Tag

git push分支的时候不会把分支上的tag带过去, 需要手动push
git tag -a v2.0 -m "An even stabler version of the website"
git push mary master

git push mary v2.0手动push tag

The remotes listed in git remote are merely bookmarks for a full path to anotherrepository.
That said, it’s important to note that remotes are for people, whereas branches are for topics.

Centralized Workflows

Create a Bare Repository (Central)

cd /path/to/my-git-repo
cd ..
**git init --bare central-repo.git**
该命令生成了一个.git文件夹, 内容和其他仓库的.git文件夹里的一样
—bare 告诉Git我们不要working directory
A central repository is only supposed to act as a storage facility—not a development environment.

Update Remotes (Mary and You)

将central-repo.git分别添加到Mary和我的远程仓库
cd marys-repo
git remote rm origin 移除仓库
git remote add origin ../central-repo.git

cd ../my-git-repo
git remote add origin ../central-repo.git
git remote rm mary

Push the Master Branch (You)

目前的中心仓库是空的,将我们的master分支push到中心仓库
cd my-git-repo
git push origin master
git log
会发现中心仓库已经拥有了master分支的所有commits

Add News Update (You)

在my-git-repo创建新的分支, 做一些修改, 提交

git checkout -b news-item
git add news-3.html index.html
git status
git commit -m "Add 3rd news item"

Publish the News Item (You)

如果是一个人开发, Publish意思是将分支和master分支合并
在Centralized Workflow, publish意思是先合并到master, 再push到中心库

git checkout master
git merge news-item
git branch -d news-item
git push origin master

Update CSS Styles (Mary)

Mary生成了一个新的分支, 做了2次commit
在push到中心库前, 用git rebase将2个commit合并成了一个commit
千万不要在推送到中心库之后再rebase, 一定要在之前做
Never, ever rebase commits that have been pushed to a shared repository.
If you need to change a public commit, use the **git revert** command
而且也不要将其他分支push到中心库,因为其他人不知道那是什么,出发你们约定好了开发这个分支

Publish CSS Changes (Mary)

git checkout master
git merge css-edits
git branch -d css-edits
git push origin master

Pull in Changes (Mary)

git fetch origin 先更新本地的远程仓库
git log master..origin/master
git log origin/master..master 查看差异

可以理解为mary的master分支和远程的master分支分叉了
使用git rebase将mary的master与origin/master合并, 使mary的最新commit在最前面
git rebase origin/master
git push origin master

Pull in Changes (You)

最后回到自己的仓库,从central repo获取mary的更新

cd ../my-git-repo
git fetch origin
git log master..origin/master --stat
git log origin/master..master --stat
git merge origin/master

Distributed Workflows

centralized workflows的缺点是任何人都可以push snapshots到中心库

Bitbucket

https://bitbucket.org/
在Bitbucket注册一个账号
注册的邮箱要和本地的git config —global的一致

在Bitbucket上新建一个public repo
这就相当于 git init --bare
注意: 什么都不要勾,不要选yes,只要一个空库

Push to the Public Repository (You)

cd /path/to/my-git-repo
git remote rm origin
git remote add origin https://<username>@bitbucket.org/<username>/my-git-repo.git
git push origin master

这里是用https方式添加的远程仓库, push时要输密码,可以改用SSH方式

Clone the Repository (John)

John想要帮助我们修改项目
先将远程仓库克隆到本地 ( GitHub或Bitbucket可以先Fork )
**git clone http://bitbucket.org/<username>/my-git-repo.git johns-repo** 注意克隆时可以重命名
**cd johns-repo**
设置用户信息
git config user.name "John"
git config user.email john.example@rypress.com

Add the Pink Page (John)

git add pink.html index.html
git status
git commit -m "Add pink page"

Publish the Pink Page (John)

John需要把他贡献的代码推送到我们的公共仓库
但事实上他也无法直接推送, 因为https要密码, SSH需要密钥
Instead, he’ll create his own Bitbucket repository that we can pull contributions from.

John在Bitbucket创建了一个仓库, 把pink page分支推送上去

git remote add john-public https://<username>@bitbucket.org/<username>/johns-repo.git
git push john-public pink-page

现在john只需要告诉我们他的仓库的链接( GitHub或Bitbucket可以直接pull request )

http://bitbucket.org/<username>/johns-repo.git

是http协议的, 允许任何人fetch, 但不可以push

View John’s Contributions (You)

cd ../my-git-repo
git remote add john http://bitbucket.org/<username>/johns-repo.git
git fetch john
git branch -r
git log master..john/pink-page --stat
git checkout john/pink-page

Never blindly merge content from a third-party contributor.

Integrate John’s Contributions (You)

如果赞同john的更改,将他的代码合并到master

git checkout master
git merge john/pink-page

Publish John’s Contributions (You)

将合并后的代码推送到public repo
git push origin master

Update Mary’s Repository (Mary)

注意, Mary添加的也是http协议的公开地址

cd ../marys-repo
git remote rm origin
git remote add origin http://bitbucket.org/<username>/my-git-repo.git
git checkout master
git fetch origin
git rebase origin/master

Update John’s Repository (John)

John不该用本地的pink-page分支合并到master, 而应该用public repo里发布的代码
所以要先fetch, 再合并

cd ../johns-repo
git checkout master
git fetch origin
git rebase origin/master

Patch Workflows

之前的工作流都是建立在分支基础上的
我们也可以使用commit级别的工作流
it’s also possible to communicate directly on the commit level using a patch.
A patch file represents a single set of changes (i.e., a commit) that can be applied to any branch, in any order.

Change the Pink Page (Mary)

git checkout -b pink-page 创建一个分支, 并做一些修改
git commit -a -m "Change pink to a manly color" 提交修改

Create a Patch (Mary)

**git format-patch master**
这个命令的意思是为所有在当前分支,但是不在master分支的commit创建patch
执行命令后, 生成了一个.patch文件, 内容就像是一封邮件

一个patch是一个完整的commit, 有几个commit就会生成几个patch文件

Mail the Patches (Mary)

Mary需要把生成的patch文件,通过邮件等方式发送给项目管理员
项目管理员把这些patch文件放到项目中

Apply the Patches (You)

我们把mary的patch文件放在my-git-repo中
使用git am命令将patch文件生成commit

cd ../my-git-repo
git checkout -b patch-integration
git am < 0001-Change-pink-to-a-manly-color.patch
git log master..HEAD --stat
git am < 0002-Add-a-pink-block-of-color.patch
git log master..HEAD --stat

Integrate the Patches (You)

git checkout master
git merge patch-integration
git branch -d patch-integration
git clean -f
git push origin master

Update Mary’s Repository (Mary)

应当始终用“official” repository 来更新本地master, 因为官方库可能还整合了其他人的代码

cd ../marys-repo
git checkout master
git fetch origin
git rebase origin/master
git branch -D pink-page
git clean -f

As a programmer, you’re most likely to use patches when you want to fix a bug in someone else’s project. After fixing it, you can send them a patch of the resulting commit. For this kind of one-time-fix, it’s much more convenient for you to generate a patch than to set up a public Git repository.