Git in context

Before we start

Download git

Register on github

What's git?

Distributed Version Control System

Centralized

Distributed

Why git?

Faster commits
Working offline
More security
Everybody likes it!

Why git?

Source: RebelLabs 2013

Git vs Subversion

Subversion (and many others) store differences between files

Git stores a snapshop of the situation of each file

Source: Pro git

Brief introduction

Source: Greenido

Brief introduction

Source: Atlassian

Now hands on ...

Working locally

Set up

Open a terminal
Type
```
git help  
```
Create a new folder "gitTest" and access it
Type
```
git init 
```
Open .git folder

Working locally

Configure

Type
```
git config 
```

Type

git config --global user.name "yourName" git config --global user.email "yourMail"

Type
```
git config --list 
```

Working locally

git upload steps

Working locally

Staging a file

On project folder create a file "yourname.txt"
Type
```
git status 
```
Type
```
git add "yourname.txt" 
```
Type
```
git status -v
```

Working locally

Commiting a file

Type

git commit -m "added initial file" git status

Modify your file
type
```
git status  
```
Do another commit
```
git commit -a -m "Modified file" 
```
Type
```
git log 
```

Working locally

Unstaging a file

Modify your file
Type
```
git add *.txt
```
Type
```
git status 
```
Type
```
git reset HEAD 
```
Type
```
git status 
```

Working locally

getting a file back to HEAD

Open the file
Type
```
git status 
git checkout -- "filename" 
```
Type
```
git status 
```
Open file again

Working locally

- reset HEAD~: Returns the staging area to last commit but does not modify the files.
- reset --soft HEAD~:Undoes the commit but does not modify the files.

- reset --hard HEAD~: Undoes the commit and modifies the files to last commit.

Uncommiting a file

Create a new file "secondFile.txt"
Commit it (you know how)
Type
```
git log --oneline --decorate 
```

Type

git reset --soft HEAD~
git log --oneline --decorate
git status

Working locally

Adding to a commit

Type

git commit --amend -m "modified initial and added second"

Type
```
git status 
```
Type
```
git log --oneline -p
```

Branching

What it is?

Switching of timelines

Branching

Creating a branch

Type
```
git branch develop
```
Type
```
git branch 
```
Type
```
git checkout develop
```
Type
```
git branch   
```

Branching

Working on a branch

Create a new file release.txt
commit it
Type
```
git log --decorate
```
Type command ls / dir
Type
```
git checkout master
git log  --decorate
```
Type command ls / dir

Branching

Merging a branch

Add commit of one branch to the other
Two possible scenario:

There were no commits on the other branch
The other branch also had commits

Branching

Fast-forward Merging

Verify you're on master branch
Type
```
 git merge develop
```
Type
```
 git log --decorate
```

Branching

Recursive Merging

Type
```
git checkout -b featureX
```
Add a file to it and commit
Go to develop branch
Modify "release.txt" file and commit
Type
```
git merge featureX 
```
If a vi screen appears, don't panic. just :wq!

Type

git log --graph --oneline --decorate --all

Branching

Merge conflict

Occurs in a recursive merge when a file has been modified on two branches
Git will stop the merging and wait until resolution.
Process:

Modify file
Stage file
Commit change

Branching

Solving a merge conflict

Go to branch featureX
Edit and commit file feature.txt
Go to branch develop and do the same
Type
```
git merge featureX
```
Open and modify file
Type
```
git add -all
 git commit
```

Branching

Deleting a branch

Type
```
git branch -d featureX 
```
Type
```
 git branch 
```
Type
```
git log --decorate
```

Branching

Source: Atlassian

Rebase

Move all changes on one branch that are not on the other to a temporary stack.
Apply all the changes of the other branch on the first branch
Apply all the changes of the temporary stack.

Rebase is another way of merging. What it does is :

Do not merge the upstream develop with your feature branch; rebase your branch on top of the upstream develop.

Never rebase shared commits. Rebase only the branch where no one have checked in yet

Rebase vs. Merging

Branching

Rebasing

Branching

Create branch featureXX
Add and commit a new file on it
Checkout to develop, modify and commit a file
Type
```
git rebase featureXX
```

Type

git log --graph --oneline --decorate --all
git branch -d featureXX

Branching

Rebase conflict

Changes on the same file also generate conflict just like merge
To solve the problem:

Edit manually the conflict
git add <file>
git rebase --continue

Going remote!

What is a remote and what I do with it?

A central repository where different developers can upload and download their commits from their local repository.

Going remote!

Creating a remote (on github)

Go to github
On your profile, new repository
Name it git-workshop
Copy the HTTPS url !!!

Going remote!

Adding a remote

Type
```
git remote add origin URL 
```
Type
```
git remote -v  
```

Going remote!

Pushing to remote

Type
```
git push -u origin develop
```
Enter your github name and pass
Go to github and watch commit log

Going remote!

Cloning a repository

Go up on your folders (cd .. )

Type

git clone https://github.com/bgorriz/git-workshop.git

Go to git-workshop folder
Type
```
git remote -v 
```
Type
```
git remote show origin
```
Type
```
git log --oneline --decorate 
```

Going remote!

Pulling from remote

Type
```
git pull 
```
Type
```
git log --decorate
```

Going remote!

What pull does

It is just :

git fetch : Downloads remote commits and creates a new branch on the local repository with those changes named origin/develop
git merge origin/develop: Same as we did at branching

Going remote!

Recursive merge on pull

Copy "yourname".txt to this folder
Commit your changes
Push your changes (you should receive an error)
Type
```
git pull 
```
Type
```
git log  
```
Now really push your changes

Going remote!

Merge conflict

Modify bgorriz.txt and commit
Push your change!
If you pull, there is a conflict merging.
Solving conflict:

Edit file
git commit -a

Now a recursive merging occurs

Remote branching

Why?

You may need other people to work on a feature.

You may want different timelines with certain commits on remote.

Remote branching

Creating a remote branch

Go back to gitTest
Go to master branch
Type
```
git push -u origin master
```
Modify the file and commit
Type
```
git push 
```
Go to github and watch branches

Remote branching

pulling a remote branch

Type
```
git branch 
```
Type
```
git pull
```
Type
```
git checkout  -b master origin/master 
```
Type
```
git remote show origin 
```

Remote branching

Removing a remote branch

Type
```
git push origin:branchName 
```
Type
```
git branch -d branchName 
```

Tagging

What is a tag?

A reference to a certain commit
Points to a important status of the repository
Generally, marks a release version

Git has two ways of tagging:

Lightweight: A pointer to a specific commit
Annotated: A full object stored in the Git database

Tagging

Creating an annotated tag

Go to master branch
Type
```
git tag -a v0.0.1 -m "version 0.0.1" 
```
Type
```
git tag 
```

Tagging

Pushing a tag

Type
```
git push origin --tags 
```
Type
```
git checkout  v0.0.1 
```

Tagging

Signed tagging

GPG can be used to sign the tag. You need a private key.
Use -s instead of -a
```
git tag -s v0.0.1 -m "tag message" 
```
To verify the tag type
```
git tag -v "tagname" 
```
You will need the signer public key.

Stashing

What is it ?

Store some file in a temporary area.

Stashing

Stash a file

Modify yourname.txt file
Type
```
git diff 

git status  
```
Type
```
git stash save 
```
Type
```
git diff

git status  
```

Stashing

Apply a stash

Type
```
git stash list 
```
Type
```
git stash  apply 
```
Type
```
git diff

git stash list  
```
Type
```
git stash drop

 git stash list  
```

reflog

What is it ?

Git keeps track of updates to the tip of branches using a mechanism called reflog. This allows you to go back to changesets even though they are not referenced by any branch or tag.

Source:  cambrico

reflog

Typical use

Restore deleted commits
Restore deleted branches

reflog

Restoring a commit

Create a new file and commit it
Type
```
git reset --hard HEAD~
```
type
```
git log 
git reflog
```
Type
```
 git reset --hard "sha"
```

reflog

Restoring a branch

Create a new branch and commit a file
Go back to develop
Type
```
git branch -D "branchname"
```
type
```
git log 
git reflog
```

Type

 git branch "branchname" "sha"
git checkout "branchname"
git log

Gitignore

What is it?

A file tha specifies intentionally untracked files that Git should ignore.

Files already tracked by Git are not affected !!

Gitignore

gitignore.io

Creating the file

Gitignore

Untracking a file

Type

git rm --chaced filename

Practical case

Before we continue

Install git flow

Scenario

International project with a distributed developer team.
Bdigital team is in management.
Use of git flow to manage development.

Git flow

What git flow is

A set git extensions to provide high-level repository operations.
An implementation of Vincent Driessen's branching model.

What git flow is not

A different VCS apart from git .
A closed software management tool.

Source: K:\ENGINYERIA SOFTWARE\PUBLIC

git flow

Permanent branches

Master branch containing production-ready code

should always reflect a production-ready state.

Develop (aka Integration, i.e. nightly builds) containing the main development

It reflects the latest delivered development changes for the next release.
It should not contain highly experimental code but should rather be considered as an "integration branch".
Work happens on the develop branch. Small changes are direct commits here.

git flow

Temporary branches

Feature branch used to develop new features,fixes or experiments for the upcoming or a distant future

Would exist as long as the feature, fix or experiment is in development.

Release branch used to prepare a new production release as well as to keep a record of the different releases that took us to a certain production version
Hotfix branch used when a critical bug is found in a production release.

git flow

naming conventions

Tags:

develop: dev-major.minor.patch_yyyymmdd (i.e. dev-1.2.07_20140110)
master: v-major.minor.patch_yyyymmdd (i.e. v-1.2_20140110)

Temporal branches:

feature: fix|feature|exp-RedmineOrJiraIssueNumber_yyyymmdd
release: rc-major.minor.patch_yyyymmdd
hotfix: hotfix-RedmineOrJiraIssueNum_date

git flow

Creating a project

create a folder gitFlowTest
Type
```
git flow init 
```
leave everything by default
Type
```
git branch 
```

git flow

Creating git flow project from existing one

create a git project gitFlowTest
Add remote repository
```
git@github.com:bgorriz/gitflowTest.git
```
Add some commits to master

Type

git config push.default current
git flow init
git push -u origin develop
git remote

git flow

Cloning a project

Type

git clone git@github.com:bgorriz/gitflowTest.git

Enter the project folder
Type
```
git flow feature 
```

Type

git config push.default current
 git flow init -d
git remote show origin

git flow

Developing a feature

Team in charge of feature

Type

```
git flow feature start "convention"
```

Type

```
git branch
```

Make some commits
Type

```
git log --oneline
```

git flow

Publishing a feature

Team in charge of feature:

Type

```
git flow feature publish "covention"
```

Go to github and look branches

git flow

Pulling a feature

Second team :

Type

git flow feature track "convention"
git remote show origin
git log --oneline

Create another file ,commit and push it

git flow

Finishing a feature

First team:

Commit final change
Type

git pull --rebase 
git flow feature finish  -F "convention"

Type
```
git branch 
git log 
git push
```

git flow

Finishing a feature

Second team:

Type

git checkout develop
git branch -d feature/"convention"
git pull --rebase

Type
```
git branch 
git log
```

git flow

Starting a release

Type:

git flow release start rc-1.0.0_20140121
git branch

git flow

Fixing a release

Add file to branch and commit
Optional: publish the release for team working just as we did with feature

git flow

Finishing a release

Type

git flow release finish rc-1.0.0_20140122
git push 
git push --tags

Go to branch develop

Type

git status
git pull --rebase
git push
git log

git flow

hotfixes

Type

git flow hotfix start hotfix-002_20140122
git branch

Modify some files and commit

Type

git flow hotfix finish hotfix-002_20140122
git branch
git pull --tags

Also

git revert
git alias
git clean
git blame
git bisect
git cherrypick
git submodules
....

More info

Official Pro git documentation
Git cheat sheet 1 2 3
Code school Git courses
git flow cheat sheet
When in git ...

Danke schön

Git in context

By Borja Gorriz Hernando

Git in context

Presentacio d'introduccio al sistema de control de versions GIT

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