Using git in Xcode 4

更新日期: 2011/02/18
參考資料:
1. Version Control System with XCode 4 and Git Tutorial | Smart Apps
   http://www.smartapps.co/2011/01/version-control-system-with-xcode-4-and-git-tutorial/

2. Help.GitHub - Generating SSH keys (OSX)
   http://help.github.com/mac-key-setup/

3. Help.GitHub - Working with SSH key passphrases
   http://help.github.com/working-with-key-passphrases/

4. gist: 830465 - gitignore file for Xcode Projects- GitHub
   https://gist.github.com/830465

5. Sample .gitignore files for various projects
   http://sujee.net/tech/articles/gitignore/


一. 環境:
     1. Mac OS X: 10.6.6 Snow Leopard
     2. Xcode: 4.0 GM (Golden Master)
     3. Git: 1.7.4-x86_64-leopard


二. set up a remote depositor(貯藏所):
    A. 在 Github.com 註冊一個賬號: Sign up for GitHub - GitHub
        說明: free for public repositories; paid for private repositories.
  
    B. 建立一個新的 remote Repository:
       進入 Create a New Repository , 建立一個新的 Repository:
       說明: 在此 Project Name 為: git_repository, 會與 四. 所建立的
                local repository 同名(可以用產品名稱來命名).
               

      按下 Create Repository 後, 會出現相關步驟的說明, 這邊先參考, 之後就會作到.

     備註: 二個超連結
             Importing a Subversion Repo? Click here

             When you're done: Continue
             // https://github.com/your-account/git_repository

    C. Generating SSH keys on OS X:
       1. 打開終端機, 先檢查 ssh key 目錄是否存在:
          $ cd ~/.ssh
          $ ls
         
          說明: a. 此目錄下, 如果已有存在的 keypair (預設為: id_rsa, id_rsa.pub),
                       且想要使用的話, 就不必再產生一次.

                   b. 或者除了移除之前的 keypair 外, 也可以作備份:
                      $ mkdir key_backup
                      $ cp id_rsa* key_backup
                      $ rm -rf id_rsa*
 
                   c. ssh 預設會使用 ~/.ssh 目錄下, 名稱為以下的 keys:
                      id_rsa, id_dsa 或 identity.

       2. 產生 RSA keypair:
          $ ssh-keygen -t rsa -C "lanli0210@gmail.com"

          Generating public/private rsa key pair.

          Enter file in which to save the key (/Users/lanli/.ssh/id_rsa):
          // 直接按 enter, 使用預設值即可
        
          Enter passphrase (empty for no passphrase):  // 輸入 passphrase
          Enter same passphrase again:                         // 再次輸入 passphrase

          Your identification has been saved in /Users/lanli/.ssh/id_rsa.
          Your public key has been saved in /Users/lanli/.ssh/id_rsa.pub.
         
          The key fingerprint is:
          bf:96:7d:8a:16:f7:a7:93:b6:08:23:34:77:c0:b1:fe lanli0210@gmail.com
         
          The key's randomart image is:
          +--[ RSA 2048]----+
          |          .      |
          |         . o     |
          |          +      |
          |         . .     |
          |        S o .    |
          |       . +.o.    |
          |        . +=E. . |
          |         .+=..* .|
          |         oo o+o= |
          +-----------------+
         
          說明:  1. 這時用 ls 就可以看到二個檔案: id_rsa 與 id_rsa.pub
                    2. 如果不使用預設的 key names 或要將 keys 存放在別的目錄,
                       則需要執行: ssh-add path/to/my_key 讓 ssh 知道 keys 在哪裡.

    D. Adding the key to your GitHub account:
       1. 打開 Browser 進入: git hub account page
       2. 先點選左邊 "SSH Public Keys", 再點 "add another public key"
       3. 先從終端機 copy public key: id_rsa.pub 的內容到 clipboard(剪貼板):
          $ cat ~/.ssh/id_rsa.pub | pbcopy
          說明: 如此以確保 key 的內容不會包含換行或空白.

       4. 在 Key 的欄位內貼上 public key 的內容: command + v

      

       5. 如果 Title 欄位留白未輸入的話, 預設會使用 key comment (your email)
          當作 Title.
       6. 接著按下: "Add key" 結果如下, 產生了一個 public key.

    E. 測試 key 是否正常運作: 用 ssh 連到 github.com
       $ ssh git@github.com
      
         The authenticity of host 'github.com (207.97.227.239)' can't be established.
         RSA key fingerprint is 16:27:ac:a5:76:28:2d:36:63:1b:56:4d:eb:df:a6:48.
         Are you sure you want to continue connecting (yes/no)? yes

         Warning: Permanently added 'github.com,207.97.227.239' (RSA) to the list of known hosts.
        
         接著, 輸入密碼:

         Identity added: /Users/lanli/.ssh/id_rsa (/Users/lanli/.ssh/id_rsa)
         PTY allocation request failed on channel 0
         Hi lanli! You've successfully authenticated, but GitHub does not provide shell access. Connection to github.com closed.

         說明: 有出現上方的 You've successfully authenticated 就代表成功了.


三. 用 Xcode 4 建立一個 Workspace (選擇性):
     A. 特點: 1. 方便組織多個專案.
                   2. 可以在同一個地方幫多個專案 commit changes.
                   3. Xcode 4 Workspace 允許在單一個地方儲存: 你所有的
                      projects, documents, folders, schemes 的 links(連結),
                      它並沒有控制住實際的資料; 只是一種參照到
                      projects, folders, various documents 的自由集合.

     B.步驟: 打開 Xcode 4 > File > New > New Workspace
                 瀏覽要存放的位置後, 然後給個名稱.
                 (在此: 路徑為 /Lanli/RD ; 名稱為: Xcode4projects )

四. 建立 Local Repository:

     A. 下載並安裝 Git: http://git-scm.com/download
         在此採用版本: git-1.7.4-x86_64-leopard

     B. 打開終端機, 告訴 Git 你的 user name 跟 email:
        $ git config --global user.name "Lanli Chen"
        $ git config --global user.email lanli0210@gmail.com

     C. 建立一個新的 local repository:
        說明: 1. 之後的 projects 也會建在此目錄下.
                 2. 可將產品名稱當成 repository 的目錄名稱;
                     此目錄下再建立多個與該產品相關的專案.

        $ mkdir /Lanli/RD/git_repository
        $ cd /Lanli/RD/git_repository
        $ git init    
          // msg: Initialized empty Git repository in /Lanli/RD/git_repository/.git/

        $ touch README
        $ git add README
        $ git commit -m 'first commit'

        [master (root-commit) 3dbca1d] first commit
        0 files changed, 0 insertions(+), 0 deletions(-)
        create mode 100644 README
       
        說明: 1. 查看 git 的用法 -> git --help
                 2. git 的 online manual: Git User's Manual

五. git 環境設定:
     (僅供參考, Xcode 4 的環境已不太相同, 並且個別專案目錄下也要設定)

     A. .gitignore 檔設定
         $ cd /Lanli/RD/git_repository
         $ touch .gitignore
         $ vi .gitignore
         加入以下的內容:

# Mac OS X Finder and whatnot
.DS_Store
# Sparkle distribution Private Key (Don't check me in!)
dsa_priv.pem
# XCode (and ancestors) per-user config (very noisy, and not relevant)
*.mode1
*.mode1v3
*.mode2v3
*.perspective
*.perspectivev3
*.pbxuser
# Generated files
VersionX-revision.h
# build products
build/
*.[oa]
# Other source repository archive directories (protects when importing)
.hg
.svn
CVS
# automatic backup files
*~.nib
*.swp
*~
*(Autosaved).rtfd/
Backup[ ]of[ ]*.pages/
Backup[ ]of[ ]*.key/
Backup[ ]of[ ]*.numbers/

         存檔並退出.

     B. .gitattributes 檔設定
         $ cd /Lanli/RD/git_repository
         $ touch .gitattributes
         $ vi .gitattributes
         加入以下的內容:

*.pbxproj -crlf -diff -merge

         存檔並退出.

         說明: The line in .gitattributes treats your Xcode project file as a binary. This prevents Git from trying to fix newlines, show it in diffs, and excludes it from merges. Note that you will still see it shown as a conflict in merges, although the file won't have changed. Simply commit it and things should be good.

六. 加入 Projects:

     A. 用 Xcode 新增一個(或多個) projects 放在 C. 建立的 local repository 下:
         Xcode 4 > File > New > New Project
         瀏覽要存放的位置後, 然後給個名稱.
         (在此: 路徑為 /Lanli/RD/git_repository ; 名稱為: helloGit )


     B. 將此專案加入 repository:
        $ cd /Lanli/RD/git_repository
        $ git add helloGit
        $ git commit -m 'helloGit project added'

        [master 0459168] helloGit project added
         18 files changed, 1484 insertions(+), 0 deletions(-)
         create mode 100644 helloGit/helloGit.xcodeproj/project.pbxproj
         create mode 100644 helloGit/helloGit.xcodeproj/xcuserdata/lanli.xcuserdatad/xcschemes/helloGit.xcscheme
         ......

七. 將 project 的 changes push 到 remote Repository:

     A. 語法: git remote add origin git@github.com:username/ProjectName
        $ cd /Lanli/RD/git_repository
        $ git remote add origin git@github.com:lanli/git_repository.git
          // 如果出現訊息: fatal: remote origin already exists.
          // 先執行: git remote rm origin ; 然後再重新 add 一次此步驟.
        $ git push origin master        

         Counting objects: 31, done.
         Delta compression using up to 2 threads.
         Compressing objects: 100% (25/25), done.
         Writing objects: 100% (31/31), 11.42 KiB, done.
         Total 31 (delta 3), reused 0 (delta 0)
         To git@github.com:lanli/git_repository.git
         * [new branch]      master -> master

     B. 接著便可以 refresh account page, 並進入 Public Repositories 內的專案.

 

   
     C. 點進 git_repository 裡看看:

     D. 可再點進 helloGit 裡看看:
        可看到所有從 local repository 所 commits 進來的檔案.

   

八. Xcode 4 的 Remote Repository:

     A. 到 Xcode 4 的 Repositories 設定頁籤:
         Xcode 4 > 右上方 Organizer > 切到 Repositories tab , 會看到 local repository,
         圖中有顯示:
         Location /Lanli/RD/git_repository
         Type Git

     B. 當有修改 source code, 可先執行 local 的 commit:
        select modified file (檔名右方會有一個 M 符號 ) > 右鍵 >
        Source Control > Commit Select Files.

       

     C. 同步更新到 remote repository:
        $ cd /Lanli/RD/git_repository
        $ git push origin master
  
    說明: 更新 remote Repository 的專案後可看到:
            name                                    age                       message
            helloGitViewController.h      5 minutes ago       add comment test

     D. 如果要從 remote repository 取得最新的版本:
        $ cd /Lanli/RD/git_repository
        $ git pull origin master