git introduction

Git IntroductionFast Version Control

Who am I

•Gareth Hall

•Lead Developer and Hyundai New Zealand

•Director at Communica (http://communica.co.nz)

What is git?

•Git is a distribute version control system developed by Junio Hamano & Linus Torvalds.

•Git does not use a centralised server.

•Git runs on major operating system like OS X, Windows, Unix & Linux

Why it’s named git?

•Quoting Linus: “I’m egotistical, and I name all my projects after myself. First Linux, now git”

•Def: git - British slang for “pig headed, they are always correct , argumentative”

What does git do?

•Git tracks changes to content.

Advantages of git• Everything is local (almost)

• Fast

• Every clone / branch is a backup

• Work offline

• No single point of failure

• Lightweight

• Branching is cheap and merging is easy

• Many different workflows possible

• Distributed

• Every file and commit is checksummed

• Staging area

• Free and open source

Three States

Individual Workflow

Collaborative Workflow

Gitflow 1

Gitflow II

Basic CommandsSyntax: git <subcmd>

git init•Create an empty git repository or reinitialize an existing one

#:>git init

Initialized empty Git repository in /Users/garethhall/Sites/git_intro/.git/

git status• Show the working tree status

#:>git status

# On branch master

#

# Initial commit

#

# Untracked files:

# (use "git add <file>..." to include in what will be committed)

#

# includes/

# index.php

nothing added to commit but untracked files present (use "git add" to track)

git add

•Add file contents to the index

•git add .

•git add <filename> <filenname>

git status#:>git add .

#:>git status

# On branch master

#

# Initial commit

#

# Changes to be committed:

# (use "git rm --cached <file>..." to unstage)

#

# new file: includes/helpers.php

# new file: index.php

#

git commit•Record changes to the repository

#:>git commit -m "first commit"

[master (root-commit) 5f8a8d4] first commit

2 files changed, 48 insertions(+)

create mode 100644 includes/helpers.php

create mode 100644 index.php

git log•Show commit logs

#:>git log

commit 5f8a8d486ae1656b51194186c0dfb97ae1ec9835

Author: Gareth Hall <gareth@communica.co.nz>

Date: Sat Feb 16 14:43:40 2013 +1300

first commit

Edit files

#:>git status

# On branch master

# Changes not staged for commit:

# (use "git add <file>..." to update what will be committed)

# (use "git checkout -- <file>..." to discard changes in working directory)

#

# modified: includes/helpers.php

# modified: index.php

#

no changes added to commit (use "git add" and/or "git commit -a")

#:>git add index.php

#:>git status

# On branch master

# Changes to be committed:

# (use "git reset HEAD <file>..." to unstage)

#

# modified: index.php

#

# Changes not staged for commit:

# (use "git add <file>..." to update what will be committed)

# (use "git checkout -- <file>..." to discard changes in working directory)

#

# modified: includes/helpers.php

#

• #:>git commit -m "Changed output to table"

[master fffacb4] Changed output to table

1 file changed, 10 insertions(+), 2 deletions(-)

#:>git status

# On branch master

# Changes not staged for commit:

# (use "git add <file>..." to update what will be committed)

# (use "git checkout -- <file>..." to discard changes in working directory)

#

# modified: includes/helpers.php

#

no changes added to commit (use "git add" and/or "git commit -a")

#:>git log

commit fffacb43627c5a44850b4b1543dc359f5d95edd6

Author: Gareth Hall <gareth@communica.co.nz>

Date: Sat Feb 16 16:10:45 2013 +1300

Changed output to table

commit 5f8a8d486ae1656b51194186c0dfb97ae1ec9835

Author: Gareth Hall <gareth@communica.co.nz>

Date: Sat Feb 16 14:43:40 2013 +1300

first commit

#:>git diff includes/helpers.phpdiff --git a/includes/helpers.php b/includes/helpers.phpindex 5c9a1fe..002256c 100644--- a/includes/helpers.php+++ b/includes/helpers.php@@ -1,5 +1,4 @@ <?php- /** * Pretty Print Helper * @@ -28,6 +27,12 @@ function dd($data, $die = false) { echo '<pre>'; var_dump($data);- echo '</pre>';- $die ? die() : null;-}\ No newline at end of file+ echo '</pre>';+ $die ? die() : null;+}++function logger($user_id, $message)+{+ $log_entry = $user_id . ',' . $message;+ return file_put_contents('log.log', $log_entry) ? true : false;+}

git diff

#:>git add .#:>git commit -m "Added logger"

[master 817dee6] Added logger 1 file changed, 9 insertions(+), 4 deletions(-)

#:>git log --oneline --decorate

817dee6 (HEAD, master) Added loggerfffacb4 Changed output to table5f8a8d4 first commit

git show• Show various types of objects

#:>git show fffacb4

commit fffacb43627c5a44850b4b1543dc359f5d95edd6Author: Gareth Hall <gareth@communica.co.nz>Date: Sat Feb 16 16:10:45 2013 +1300

Changed output to table

diff --git a/index.php b/index.phpindex f1f4a05..df11b0b 100644--- a/index.php+++ b/index.php@@ -10,6 +10,14 @@ if (($xml = @simplexml_load_file('https://www.bnz.co.nz/XMLFeed/portal/fcs/xml') } } -pp($bnz_rates, true);-+print '<table border="1">';+ print '<tr>';+ print '<th>Code</th><th>Rate</th>';+ print '</tr>';+ foreach ($bnz_rates as $code => $rate){+ print '<tr>';+ print '<th>' . $code . '</th><th>' . $rate . '</th>';+ print '</tr>';+ }+print '</table>';

git branch•List, create, or delete branches

#:>git branch outputHelper

#:>git branch

* master

outputHelper

git checkout•Checkout a branch or paths to the working tree

#:>git checkout outputHelper

Switched to branch 'outputHelper'

#:>git branch

master

* outputHelper

Develop new Feature

#:>git status

# On branch outputHelper

# Changes not staged for commit:

# (use "git add <file>..." to update what will be committed)

# (use "git checkout -- <file>..." to discard changes in working directory)

#

# modified: includes/helpers.php

# modified: index.php

#

# Untracked files:

# (use "git add <file>..." to include in what will be committed)

#

# includes/.DS_Store

# includes/output_helper.php

no changes added to commit (use "git add" and/or "git commit -a")

#:>git add includes/helpers.php

#:>git commit -m 'Added doc block to logger function'

[outputHelper df78fc4] Added doc block to logger function

1 file changed, 8 insertions(+)

#:>git commit -a -m 'Refactored with new table output helper'

[outputHelper 51da4b7] Refactored with new table output helper

3 files changed, 38 insertions(+), 11 deletions(-)

create mode 100644 includes/.DS_Store

create mode 100644 includes/output_helper.php

#:>git log --oneline --decorate --graph

* 51da4b7 (HEAD, outputHelper) Refactored with new table output helper

* df78fc4 Added doc block to logger function

* 817dee6 (master) Added logger

* fffacb4 Changed output to table

* 5f8a8d4 first commit

#:>git checkout master

Switched to branch 'master'

#:>git log --oneline --decorate --graph

* 817dee6 (HEAD, master) Added logger

* fffacb4 Changed output to table

* 5f8a8d4 first commit

git merge• Join two or more development histories together

#:>git merge outputHelper

Updating 817dee6..51da4b7

Fast-forward

includes/.DS_Store | Bin 0 -> 6148 bytes

includes/helpers.php | 8 ++++++++

includes/output_helper.php | 36 ++++++++++++++++++++++++++++++++++++

index.php | 13 ++-----------

4 files changed, 46 insertions(+), 11 deletions(-)

create mode 100644 includes/.DS_Store

create mode 100644 includes/output_helper.php

#:>git log --oneline --decorate --graph

* 51da4b7 (HEAD, outputHelper, master) Refactored with new table output helper

* df78fc4 Added doc block to logger function

* 817dee6 Added logger

* fffacb4 Changed output to table

* 5f8a8d4 first commit

git reset

•Reset current HEAD to the specified state

git push

•Update remote refs along with associated objects

git fetch

•Download objects and refs from another repository

git merge

•Join two or more development histories together

git pull

•Fetch from and merge with another repository or a local branch

•fetch + merge

How in Drupal?

•Add all of Drupal to git

•Use the Features module to move configuration

•UUID Features to move content (alpha!)

Git Hosting Service

•Bitbucket (htt://bitbucket.org)

•Github (http://github.com)

•Run your own

•Gitosis

•Gitolite

Deployment

•Shell Access

•Continous Integration

•I don’t have shell access

•Setup your server as a remote

Deployment with shell

Continous Intergration

•Heroku (http://heroku.com)

•Pagoda (http://pagodabox.com)

•Bamboo (http://atlassian.com/software/bamboo)

I don’t have shell•Deploy (http://www.deployhq.com)

Server as Remote•Will need to use git hooks

Git Hooks

Git Hooks• #>vim post-receive

• #!/bin/sh

• cd ..

• GIT_DIR='.git'

• umask 002 && git reset --hard

Git GUI’s

Resources•Git (http://git-scm.com)

•Wiki (http://en.wikipedia.org/wiki/Git_(software))

•Git Essentials (https://tutsplus.com/course/git-essentials/)

•Change Management and Version Control (http://buildamodule.com)

Visual Version Control

Gource (http://code.google.com/p/gource/)

Questions