Git Quickstart

Revision Control for Rock Stars

Introductions

How would you know this course was valuable a week from now?

Course Outline

• Getting Setup• Git: The Big Picture• Everyday Git• Branching• Merging & Rebasing• Other Random Gitness• Putting It All Together• Where to from here?

Outcomes & Compentencies

• Install and Configure Git for Windows• Create local and shared Git repos• Add, Remove & Commit Files to repos• View History of Files / Work with Diffs & Blames• Branch, Tag and Merge & Rebase Branches

(with Conflicts)• Back out of trouble & drama• Be able to Push, Pull, Fetch, Clone, Diff &

Branch Remote Repos• Formulating Team Workflows with Git

Philosophy

• “One must learn by doing the thing; for though you think you know it, you have no certainty, until you try.” Sophocles

• “Where there are no oxen, the manger is clean, but abundant crops come by the strength of an ox.” Jewish Proverb.

• Experiment. Go Crazy. Type like a madman.

MODULE 0: GIT - THE BIG PICTURE

What? When? Why?

Git: The Big Picture

Use Cases

• Individual Developer• Local Workgroup• Distributed Workgroup• Offline Usages

Git vs Svn vs CVS vs ?

• Snapshots, not diffs• Blobs• Everything is local• Everything is fast

What’s This “Commit” Thing?

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File1.txtFile2.txt

File3.txtFile1.txt

File4.txt

Git WorkflowWorkin

g Directo

ryStaging

Area (Index)

Repository

Add

Commit

Checkout

1. GETTING SETUPGetting things installed…

GUIs or Commandline or IDE?

• Git Bash• Posh Git (Powershell)• GitHub for Windows• Tortoise Git• Eclipse Git / IntelliJ Git / Visual Studio

Git Plugin / etc

Download Git for Windows

Installation Options

The Magic Path Dialog

Checkout Conventions

Commandline Once-off Magic

• git config --global user.name “Glen Smith”

• git config --global user.email “glen@bytecode.com.au”

• git config -l [--global]• git help config

MODULE 2: EVERYDAY GITThings you’ll use every single day…

Everyday Git: Getting Committed

• git init .• git init myproject

• git status

• echo This is a sample file > sample.txt

Adding and Committing

• git add .• git add myfile.txt myotherfile.txt• git add “**.txt”• git status• git commit -m “My first commit!”• git commit• git commit -am “Add all files and

commit. I live on the edge”

Formatting Commits

• set GIT_EDITOR=notepad• git config --global core.editor

“notepad“

• First line for short form.• Second line blank.• Third line for a long description of the

commit

Diff & Blame

• git diff• git blame /path/to/my/file.txt• git gui blame /path/to/my/file.txt• git whatchanged /path/to/my/file.txt • gitk /path/to/my/file.txt

Viewing History

• git log • git log --oneline• git log --oneline -3• git log -p• git log --since “last week” --until “2

days ago”• gitk

What’s with the SHA1?

Deleting and Renaming Files

• git rm badfile.txt

• git mv oldname.txt newname.txt

• git clean -n (dry run)• git clean -f (force)

Ignoring Files

• .gitignore• Ignore file(s), directories, patterns

(one per line)• Great for ignoring files and

directories in your project• Specially good for build artefacts and

generated binaries

Unstaging a File

• git reset HEAD myfile.txt• git checkout myfile.txt• git rm –cached myfile (only pre first

commit)

Amending A Commit

• (stage the files you want)• git commit --amend

The Reflog

• git reflog• git checkout <your-commit-sha1>• git checkout master

MODULE 3: BRANCHING & TAGGING

Working with Lines of Development

Our Story So Far…

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What could you use branches for?

• Bug fixes• Experimental features• Release branches• Integration Branches (CI)

In Reality…

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Developer Branches for

an experimental

feature..

Merges his Changes back to the master

Branching

• git branch• git branch mynewbranch• git checkout mynewbranch• git checkout -b

mynewcheckedoutbranch• git branch -d deletethatbranch

Stashing

• git stash• git stash list• git stash apply• git stash pop• git stash clear

Merging

• git merge branchname• git log master..dev

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Merge creates a new commit with two parents

Handling Conflicts

• git status• git checkout --ours myfile.txt• git checkout --theirs theirfile.txt

Helpful Branch Tools

• gitk• git log --graph --oneline

Tagging

• git tag 1.0• git tag -f 1.0• git tag -a 1.0• git tag

Working with Remotes

• mkdir ourrepo.git• cd ourrepo.git• git init --bare• git clone file://c:/data/shared/ourrepo.git (or)• git remote add origin file://

c:/data/shared/ourrepo.git• git push origin master• git remote -v

Pushing, Fetching, Pulling

• git pull• git fetch• git push• git push --tags• git log master..origin/master

Remote Branches

• git push origin mybranch• git push origin• git branch -r• git checkout -b mybranch

origin/mybranch

• git config --global push.default matching

• git config --global push.default simple

Deleting Remotes

• git branch -r • git push origin :mybranch• git push origin --delete mybranch• git remote prune

MODULE 4: MERGING AND REBASING

Back in the Day..

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Developer Branches for

an experimental

feature..

Merges his Changes back to the master

Enter The Rebase…

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Warning!

• ONLY rebase on a local repo, never rewrite shared history

• If you’ve pushed your changes, live with it

• You can use git revert to develop compensating commits

Rebase Essentials

• git checkout mybranch• git rebase master• git checkout master• git merge mybranch

And when there are conflicts?

• git rebase --abort• git rebase --skip• git rebase --continue

Rewrite History with Rebase

• git rebase -i <parent-of-the-commit-to-start-from>

• (entries will appear from oldest to newest)

MODULE 5: OTHER RANDOM GITNESS

Stuff that doesn’t fit elsewhere…

Git Aliases

• git config --global alias.co checkout• git config --global alias.ll “log --

oneline –graph” • git config -l• git config --unset alias.ll

Soft and Hard Resets

• Provide a way of moving HEAD in your current branch

• Hard resets throw away working tree• Soft resets preserve working

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Normally HEAD would point to here

Deployment Options

• Create a bare repo on the shared drive and use file: protocol

• Host it on a shared Unix host and use the ssh: protocol

• Run a local git daemon!

Submodules

• git submodule add <your-git-submodule-repo>

• git submodule init• git submodule update

Git Revert

Git Bundle

MODULE 6: PUTTING IT ALL TOGETHER

Choosing a Team Workflow

1. Master is always golden (merge from CI/Dev branch)

2. Branch off master approaching release

3. Release Branch Centric4. <Your Strategy Here>

Git(hub) Flows

• Anything in master is deployable• To work on something new, create a

new named branch off master and push it remotely

• After signoff, merge it to master (via a Jenkins job!)

The Monster Exercise

MODULE 7: WHERE TO FROM HERE?

Now you know the basics…

Useful Books & Videos

Useful Sites

• http://refcardz.dzone.com/refcardz/getting-started-git

• http://git-scm.com/book

• http://stackoverflow.com/questions/tagged/git

• http://try.github.com

Please Help Us Improve

• Please fill in a feedback card telling us how we can improve this experience

• We’d love a testimonial too

Thanks for Coming!

• Go forth and Git!