簡單介紹git

1. Git Introduction
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2. 為什麼要做版本控制？？
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3. LocalVersion Control Systems
• 在自己電腦裡，建立⼀一
個版本資料庫
• 最簡單的作法
Problem:如何協作？？
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4. CentralizedVersion Control Systems
• Server上，會儲存所有的
版本及記錄
• Checkout & Commit
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5. DistributedVersion Control Systems
• 大家都有完整的資料庫
• 大家都能獨立工作
• Server壞了只要拿到⼀一份
完整的資料庫便可復原
• Git, Mecurial(hg),
bazaar(bzr)
Problem:相較於Centralized
混亂。
提供好的Branch機制解決
此問題。
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6. https://help.github.com/articles/set-up-git
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7. Set up Git
https://help.github.com/articles/set-up-git
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8. $ git config --global user.name "Your Name Here"
# Sets the default name for git to use when you commit
$ git config --global user.email "your_email@youremail.com"
# Sets the default email for git to use when you commit
$ git credential-osxkeychain
# Test for the cred helper
Usage: git credential-osxkeychain <get|store|erase>
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9. $ git credential-osxkeychain
# Test for the cred helper
git: 'credential-osxkeychain' is not a git command. See 'git
--help'.
$ curl -s -O http://github-media-downloads.s3.amazonaws.com/
osx/git-credential-osxkeychain
# Download the helper
$ chmod u+x git-credential-osxkeychain
# Fix the permissions on the file so it can be run
$ sudo mv git-credential-osxkeychain /usr/local/git/bin
# Move the file so git can access it
# Password: [enter your password]
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10. $ git config --global credential.helper osxkeychain
# Set git to use the osxkeychain credential helper
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11. Get a Github account
https://github.com/
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12. https://help.github.com/articles/generating-ssh-keys
Generate SSH Keys
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13. $ cd ~/.ssh
$ ls
config id_rsa id_rsa.pub known_hosts
$ mkdir key_backup
$ cp id_rsa* key_backup
$ rm id_rsa*
$ ssh-keygen -t rsa -C "your_email@youremail.com"
# Creates a new ssh key using the provided email
Generating public/private rsa key pair.
Enter file in which to save the key (/Users/you/.ssh/id_rsa):
[Press enter]
Enter passphrase (empty for no passphrase): [Type a
passphrase]
Enter same passphrase again: [Type passphrase again]
Your identification has been saved in /Users/you/.ssh/id_rsa.
Your public key has been saved in /Users/you/.ssh/id_rsa.pub.
The key fingerprint is:
01:0f:f4:3b:ca:85:d6:17:a1:7d:f0:68:9d:f0:a2:db
your_email@youremail.com
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14. $ pbcopy < ~/.ssh/id_rsa.pub
# Copies the contents of the id_rsa.pub file to your clipboard
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15. $ ssh -T git@github.com
# Attempts to ssh to github
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)?
Hi username! You've successfully authenticated, but GitHub
does not provide shell access.
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16. Create a Repo
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17. 17

18. 18

19. $ mkdir ~/Hello-World
# Creates a directory for your project called "Hello-World"
in your user directory
$ cd ~/Hello-World
# Changes the current working directory to your newly
created directory
$ git init
# Sets up the necessary Git files
Initialized empty Git repository in /Users/you/Hello-
World/.git/
$ touch README
# Creates a file called "README" in your Hello-World
directory
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20. $ git add README
# Stages your README file, adding it to the list of files to
be committed
$ git commit -m 'first commit'
# Commits your files, adding the message "first commit"
$ git remote add origin https://github.com/username/Hello-
World.git
# Creates a remote named "origin" pointing at your GitHub
repo
$ git push origin master
# Sends your commits in the "master" branch to GitHub
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21. Fork A Repo
$ git clone git@github.com:oboegrace/git-101.git
https://help.github.com/articles/fork-a-repo
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22. Git Basics
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23. Snapshots, Not Differences
SVN
Git
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24. Nearly Every Operation is Local
• 不只有⼀一份完整的資料
庫
• 閱讀版本歷史、提交
變更這些動作都可以
在本機進行
• 不需網路連線也可以工
作
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25. Git Has Integrity
• 使用 Checksum 來確保檔案的完整性
• 設計上只會增加資料，因此可以輕鬆復
原
• 在本機的檔案管理中，增添了Staging的
觀念
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26. TheThree States of Git
• Committed
• Data is safely stored in your local database.
• Modified
• You have changed the file but have not committed it to your
database yet.
• Staged
• You have marked a modified file in its current version to go
into your next commit snapshot.
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27. The basic workflow of Git
1. You modify files in your
working directory.
2. You stage the files,
adding snapshots of
them to your staging
area.
3. You do a commit, which
takes the files as they
are in the staging area
and stores that snapshot
permanently to your Git
directory.
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28. Using Git
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29. Installing Git
• Installing on Mac
• http://code.google.com/p/git-osx-installer
• Installing on Windows
• http://code.google.com/p/msysgit
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30. Initializing a Repository in an Existing Directory
• Repository就是⼀一份版本控制中心的版本
資料庫
• $ git init
• 資訊會放在.git資料夾裡
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31. Initial Commit
• Add files
• And commit it!
$ touch README
$ git add .
$ git commit -m 'Initial commit'
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32. Cloning an Existing Repository
$ git clone git://github.com/schacon/grit.git
Checking the Status ofYour Files
$ git status
# On branch master
nothing to commit (working directory clean)
Ignoring Files
$ cat .gitignore
*.[oa]
*~
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33. CommittingYour Changes
$ git commit
Removing Files
$ git rm grit.gemspec
rm 'grit.gemspec'
$ git status
# On branch master
#
# Changes to be committed:
# (use "git reset HEAD <file>..." to unstage)
#
# deleted: grit.gemspec
#
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34. ChangingYour Last Commit
$ git commit --amend
Unstaging a Staged File
$ git reset HEAD aFile
Unmodifying a Modified File
$ git checkout -- aFile
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35. Working with Remotes
• Branch 和 Remote 之間的互動
• 預設的 Branch 叫 Master
• 預設的 Remote 叫 Origin
• $ git pull origin :
$ git fetch origin
$ git merge origin/master
• $ git push origin master
push
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36. What a Branch Is
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37. Single commit repository data.
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38. Git object data for multiple commits.
Branch pointing into the commit data’s history.
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39. $ git branch testing
git branch <new_branch_name> 建立本地 local branch
git branch 列出目前有那些 branch 以及目前在那個 branch
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40. $ git checkout testing
This moves HEAD to point to the testing branch
此時如果commit...
git checkout <branch_name> 切換 branch
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41. 41

42. $ git checkout master
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43. $ git commit -a -m 'made other changes'
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44. http://learn.github.com/p/branching.html
Practice Branching and Merging
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45. 如何重新變回⼀一條?
• Merge
• 把岔開來的分支在往後合起來
• 通常的建議方式
• Rebase
• 把岔開來的分支裝回去主線
• 還沒Push出去的東西才可以Rebase!
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46. Basic Branching and Merging
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47. 有緊急的Bug，開了一個 hotfix branch 處理好了。
現在要怎麼處理 master?
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48. $ git checkout master
$ git merge hotfix
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49. 此時處理完iss53，那該如何Merge?
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50. $ git checkout master
$ git merge iss53
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51. Basic Merge Conflicts
• git status ⼀一下看是哪個檔案出問題
• 到出問題的檔案找問題，手動解決
• 再檢查 git status 後，用 git commit 手動
Merge (會自動生成 Merge 的 Commit Message)
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52. Rebase
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53. 除了Merge以外，我有沒有其他的辦法可以處理
掉 experiment branch?
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54. $ git checkout experiment
$ git rebase master
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55. $ git checkout master
$ git merge experiment
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56. $ git clone git@github.com:oboegrace/git-101.git
Let’s practice it!
1. Set up git https://help.github.com/articles/set-up-git
2. Generate SSH Keys https://help.github.com/articles/generating-ssh-keys
3. Create a repo https://help.github.com/articles/create-a-repo
4. Fork a repo https://help.github.com/articles/fork-a-repo
5. Be social https://help.github.com/articles/be-social
6. Normal Workflow http://learn.github.com/p/normal.html
7. Branching and merging http://learn.github.com/p/branching.html
8. Distributed Git http://learn.github.com/p/remotes.html
9. Git history http://learn.github.com/p/log.html
10.Git reference http://gitref.org/
Reference
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