GIT & GIT workflow MODELs

AS CATALYSTS OF SOFTWARE DEVELOPMENT

@lemiorhan

Lemİ Orhan ERGİN
lemiorhanergin.com

@lemiorhan
Lemİ Orhan Ergİn
CSM, PSM1

2013

Principal Software Engineer at Sony

2001

has worked in Tüsside, BYM, GittiGidiyor/eBay
and Sony as lead developer, technical leader,
technical coordinator and scrum master

2009
2
2005

using Git, but not an expert

agile
0.5M

experienced in agile transformation and
building agile culture in teams & organisations

organisational level SVN to GIT migration
projects experienced so far
doing code reviews as a daily habit

total number of views of his presentations
I love
git
I love
git
because…

I used SVN for a while
Local branching is cheap
Everything is local
Distributed
Ruby on Rails with full history
and branches weight 13Mb.

Small and efficient
It weights 115Mb in SVN
Any workflow
Each object is compressed by
zlib and transferred over wire
Lightening Fast
one by one
Huge community
More than 3M people˝
More than 5M repositories˝
GitHub… Thanks God!
Raised $100 million on July'12
git data model is

hot

It is a directed acyclic graph
Objects (blob, tree, commit, tag) are immutable
References (branch, remote) always change
Stop comparing SVN with GIT
It is not a magical version of SVN. Try to understand what it's actually doing.
“

It's a stupid content tracker. 

It tracks files and folders.

I really really designed it coming at the
problem from the viewpoint of a file
system person, I actually have
absolutely zero interest in creating a
traditional SCM system.
LINUS TOVALDS

”
git

changed the way we think of

merging
branching
workflows
git is a tool for designing vcs workflows
main branches
supporting branches
Feature development
release development
hot fixes in production

git
workflow
model
main branches

main branches are permanent branches
which are created at the very beginning
and n

ever
d

elete
d!
main branches

OPTıONAL
development

It reflects the latest
delivered development
changes for the next
release

Automatic nightly
builds

test & QA

STAGING & UAT

MASTER
Production
main branches

OPTıONAL
development

test & QA

It reflects the code which
is deployed to test/qa
environment for testing

Automatic nightly
builds

Automatically
deployed to test/qa
servers every night

STAGING & UAT

MASTER
Production
main branches

OPTıONAL
development

test & QA

STAGING & UAT

It reflects the code which
is deployed to staging/uat
environment for testing

Automatic nightly
builds

Automatically
deployed to staging
servers every night
Automatically
deployed to test/qa
servers every night

MASTER
Production
main branches

OPTıONAL
development

test & QA

STAGING & UAT

MASTER
Production

It reflects the code which
is deployed to production

Automatic nightly
builds

Automatically
deployed to staging
servers every night
Automatically
deployed to test/qa
servers every night

Automatically
deployed to
production servers
on demand
supporting branches

feature branches
HOTFIX branches
release branches
These have limited life time
and will be removed eventually
supporting branches

feature branches
HOTFIX branches
release branches
These have specific purpose

and strict rules for originating and target branches
Feature development

All feature branches should be created from

The development branch
the n

ext r
eleas
e bra

nch
Feature development

take a new feature branch

regardless of the feature size
you ca
comm n fix v
in dev on issue ery mino
elopm s direc r
like f ent b tly
ixing ranch
typos ,
Feature development

Ne

Feature 1

Feature 2

2

Feature 2 is
completed and ready for
the next release

Feature 3

xt

development Rel
ea
se
Ne

Feature development

Feature 1

Feature 1 is being
developed

Feature 2

2
1

Feature 3

xt

development Rel
ea
se
Feature development

Ne

Feature 1

Feature 2

Feature 3

xt

development Rel
ea
se

2
1
D

Feature 2 is completed and
merged back to master
Ne

Feature development

Feature 1

Feature 1 gets the
commits in Feature 2

Feature 2

Feature 3

development Rel
ea
se

2
1
D
1

xt
Ne

Feature development

Feature 1

Pulls all the commits
from other features and
resolve conflicts

Feature 2

Feature 3

development Rel
ea
se

2
1
D
1
1

xt

D
Feature development

Ne

Feature 1

Feature 2

Feature 3

xt

development Rel
ea
se

2
1
D
1

D

1
3

Feature 3 is created from
development. It has commits
of Feature 2
Feature development

Ne

Feature 1

Feature 2

Feature 3

xt

development Rel
ea
se

2
1
D
1

D

1
3
D

Feature 1 is completed and
merged back to master
Feature development

Ne

Feature 1

Feature 2

Feature 3

development Rel
ea
se

2
1
D
1

D

1
3
D

3

Feature 3 gets the
commits of Feature 1

xt
Feature development

Ne

Feature 1

Feature 2

Feature 3

development Rel
ea
se

2
1
D
1

D

1
3
D

3
3

Feature 3 pull updates
frequently

xt

D
Feature development

Ne

Feature 1

Feature 2

Feature 3

xt

development Rel
ea
se

2
1
D
1

D

1
3
D

3
3

D
D

Typo is fixed directly in
development branch
Feature development

Ne

Feature 1

Feature 2

Feature 3

development Rel
ea
se

2
1
D
1

D

1
3
D

3

Feature 3 pulls commit
about fixing the typo

3
3

xt

D
D
Feature development

Ne

Feature 1

Feature 2

Feature 3

xt

development Rel
ea
se

2
1
D
1

D

1
3
D

3
3

D
D

3
D

Feature 3 is completed
and merged back to master.
It has commits of all 3
features now.
release development

Release branch is created when

all features are ready for the next release
some
featu times w
re fre e call
eze it as
release development

Release branch is deleted when

the release completes
we w
code, ill tag t
branc no need he releas
to ke ed
h..
ep th
e
release development

el

N

t
ex

s
ea

e

R development

F
D
F
D

Completed features are
merged with development

release

MASTER
Production
release development

el

N

t
ex

s
ea

e

R development

F
D
F
D

D

All features are ready for
the next release

release

MASTER
Production
release development

el

N

t
ex

s
ea

e

R development

release

MASTER
Production

F
D
F
D

Start a release branch
when features are freezed

D
R
release development

el

N

t
ex

s
ea

e

R development

release

MASTER
Production

F
D
F
D

D
R

Only fixes are allowed
R
D
R

Bug fixes are
continuously merged back
to development brach

D
release development

el

N

t
ex

s
ea

e

R development

release

MASTER
Production

F
D
F
D

D
R
R
D
R
D
R

Release is ready now
release development

el

N

t
ex

s
ea

e

R development

release

F
D
F
D

D
R
R
D
R

Latest fixes are merged
back to development branch

D
R
D

MASTER
Production
release development

el

N

t
ex

s
ea

e

R development

release

MASTER
Production

F
D
F
D

D
R
R
D
R
D

Merge release branch
with master branch

and get a new tag

R
D
M
hot fixes in production

Fix branches are required because every fix should be

well tested and verified

it me
to rol ans, you
done i lback w may nee
n the hat yo d
fix
u’ve
hot fixes in production

el

N

t
ex

s
ea

e

R development

Hot-FIX

MASTER
Production

Hot fix is required! A
new branch is created from
production branch
M
hot fixes in production

el

N

t
ex

s
ea

e

R development

Hot-FIX

MASTER
Production

M

Fix is developed, tested and
verified. Ready to go.
H
hot fixes in production

el

N

t
ex

s
ea

e

R development

Hot-FIX

MASTER
Production

M

H

D

Hot fixes are merged back
to development branch
hot fixes in production

el

N

t
ex

s
ea

e

R development

Hot-FIX

MASTER
Production

M

H

Hot fix is merged with
production branch and
production branch is tagged

D
M
ALL FLOWS IN THE MODEL

This graphic is taken from Vincent
Driessen’s article called 

“a successful git branching model”
feature development
1

creatE permanent branches
If these does not exist

➜ git:(master)  git checkout -b development
Switched to a new branch 'development'

➜ git:(development)  git push origin development
Total 0 (delta 0), reused 0 (delta 0)
To UberProject.git
 * [new branch]   development -> development

➜ git:(development)  git branch -a
* development
  master
  remotes/origin/development
  remotes/origin/master 

it cre
branc ates de
v
pushe h from m elopme
s to r aste nt
emot r and
e
2

Pull to update

local development branch
be sure you run tests directly afterwards

➜ git:(master) git fetch origin
From UberProject
 * [new branch]   development -> origin/development

➜ git:(master) git checkout development
Branch development set up to track remote branch development from origin.
Switched to a new branch ‘development'

➜ git:(development) git pull
remote: Counting objects: 19, done.
remote: Compressing objects: 100% (8/8), done.
remote: Total 17 (delta 2), reused 0 (delta 0)
Unpacking objects: 100% (17/17), done.
From UberProject
  3eb8b34..c827c84  development -> origin/development
Updating 3eb8b34..c827c84
Fast-forward
 grails-app/controllers/org/example/BookController.groovy |  6 ++++++
 grails-app/domain/org/example/Book.groovy   |  7 +++++++
 test/unit/org/example/BookControllerTests.groovy   | 17 +++++++++++++++++
 test/unit/org/example/BookTests.groovy   | 17 +++++++++++++++++
 4 files changed, 47 insertions(+)
 create mode 100644 grails-app/controllers/org/example/BookController.groovy
 create mode 100644 grails-app/domain/org/example/Book.groovy
 create mode 100644 test/unit/org/example/BookControllerTests.groovy
 create mode 100644 test/unit/org/example/BookTests.groovy 
3

create a feature branch

from development

with a name having story id and descriptive title

➜ git:(development)  git checkout -b feature-1185-add-commenting
Switched to a new branch 'feature-1185-add-commenting' 

➜ git:(feature-1185-add-commenting)  

the t
hints itle shou
about ld giv
what e
’s in

it
4

work in your feature branch
commit early and often

Be careful!
“push early it does not mean
and often”

➜ git:(feature-1185-add-commenting) vi web-app/WEB-INF/applicationContext.xml
➜ git:(feature-1185-add-commenting) ✗ git add .
➜ git:(feature-1185-add-commenting) ✗ git commit -m "added comment for applicationContext.xml"
[feature-1185-add-commenting b6f68cc] added comment for applicationContext.xml
 1 file changed, 2 insertions(+), 1 deletion(-)

!

➜ git:(feature-1185-add-commenting) vi web-app/WEB-INF/sitemesh.xml
➜ git:(feature-1185-add-commenting) ✗ git add .
➜ git:(feature-1185-add-commenting) ✗ git commit -m "added comment for sitemesh.xml"
[feature-1185-add-commenting 0e74f89] added comment for sitemesh.xml
 1 file changed, 3 insertions(+), 1 deletion(-)

!

➜ git:(feature-1185-add-commenting) vi .application.properties
➜ git:(feature-1185-add-commenting) ✗ git add .
➜ git:(feature-1185-add-commenting) ✗ git commit -m "increased the application version"
[feature-1185-add-commenting 7ce1f07] increased the application version
 1 file changed, 1 insertion(+), 1 deletion(-)
5

rebase frequently

to incorporate upstream changes
to prevent your branch from diverging significantly

➜  git:(feature-1185-add-commenting) git fetch origin development
From UberProject
 * branch   development -> FETCH_HEAD

➜  git:(feature-1185-add-commenting) git rebase origin/development
First, rewinding head to replay your work on top of it...
Fast-forwarded feature-1185-add-commenting to origin/development. 
5

rebase frequently

to incorporate upstream changes
to prevent your branch from diverging significantly

➜  git:(feature-988-add-shelf-controller) git checkout development
Switched to branch 'development'
Your branch is behind 'origin/development' by 2 commits, and can be fast-forwarded.
  (use "git pull" to update your local branch)

➜  git:(development) git pull
Updating 4559eba..d55ee12
Fast-forward
 application.properties   |  2 + grails-app/domain/org/example/Shelf.groovy |  7 +++++++
 test/unit/org/example/ShelfTests.groovy   | 17 +++++++++++++++++
 web-app/WEB-INF/applicationContext.xml   |  3 ++ web-app/WEB-INF/sitemesh.xml   |  4 +++ 5 files changed, 30 insertions(+), 3 deletions(-)
 create mode 100644 grails-app/domain/org/example/Shelf.groovy
 create mode 100644 test/unit/org/example/ShelfTests.groovy

➜  git:(development) git checkout feature-1185-add-commenting
Switched to branch 'feature-988-add-shelf-controller'

➜  git:(feature-988-add-shelf-controller) git merge development
Updating 7761c9c..d55ee12
Fast-forward
 application.properties   | 2 + web-app/WEB-INF/applicationContext.xml | 3 ++ web-app/WEB-INF/sitemesh.xml   | 4 +++ 3 files changed, 6 insertions(+), 3 deletions(-) 

ing
th s
me tep 

e sara s onal
th xt iti
oes h e add mit
t d wit an com
i
and erge
m
6

Interactive rebase

to squash your commits

be sure that we only deal with the local commits
➜  git:(feature-1185-add-commenting) git rebase -i origin/development

git will display an editor with a list of the commits to be modified
pick 4559eba updated application version
pick d1706ae added comments for applicationContext.xml
pick d3c2734 added comments for sitemesh.xml

Now we need to tell git what to do. keep the first one as it is and change the others as “squash”
pick 4559eba updated application version
squash d1706ae added comments for applicationContext.xml
squash d3c2734 added comments for sitemesh.xml

Git squashes the commits together to one commit and opens a new editor to enter commit message
updated application version, added comments to
applicationContext.xml and siteMesh.xml files

Now the last 3 commits are squashed into one commit with a special commit message
7

merge your changes

with development branch
It’s time to merge the completed work

➜  git:(feature-1185-add-commenting) git checkout development
Switched to branch 'development'
Your branch is behind 'origin/development' by 3 commits, and can be fast-forwarded.
  (use "git pull" to update your local branch)

➜  git:(development) git pull
Updating c827c84..7761c9c
Fast-forward
 application.properties   |  2 + grails-app/controllers/org/example/ShelfController.groovy |  6 ++++++
 grails-app/domain/org/example/Shelf.groovy   |  7 +++++++
 test/unit/org/example/ShelfControllerTests.groovy   | 17 +++++++++++++++++
 test/unit/org/example/ShelfTests.groovy   | 17 +++++++++++++++++
 5 files changed, 48 insertions(+), 1 deletion(-)
 create mode 100644 grails-app/controllers/org/example/ShelfController.groovy
 create mode 100644 grails-app/domain/org/example/Shelf.groovy
 create mode 100644 test/unit/org/example/ShelfControllerTests.groovy
 create mode 100644 test/unit/org/example/ShelfTests.groovy

some
we m one push
erge, ed bef
damm ore
it!

➜  git:(development) git merge feature-1185-add-commenting
Updating 7761c9c..d55ee12
Fast-forward
 application.properties   | 2 + web-app/WEB-INF/applicationContext.xml | 3 ++ web-app/WEB-INF/sitemesh.xml   | 4 +++ 3 files changed, 6 insertions(+), 3 deletions(-)
8

push your changes to the upstream

➜  git:(feature-1185-add-commenting) git push origin development
Counting objects: 13, done.
Delta compression using up to 4 threads.
Compressing objects: 100% (7/7), done.
Writing objects: 100% (7/7), 759 bytes | 0 bytes/s, done.
Total 7 (delta 4), reused 0 (delta 0)
To UberProject.git
   7761c9c..d55ee12  development -> development 
tıps forand git branching model
efficient usage
of git
1

Learn git Command Line by heart, stop using GUI
GUI is
to do extrem
stuff ely m
like m essy w
erging hen y
and b ou need
ranch
ing.
2

Only few people should be authorised

for merging development branch to master branch
for do
durin ing a th
g mer e last
ge by revie
techn w
ical le
ads
3

check-in others code at least once a day
It’s b
when etter to
ever
c
possibheck-in
le
4

ensure that all tests are passing

before pushing to upstream
5

never rebase shared commits
rebas
no one e only th
have e bran
check ch w
ed in here
yet
6

do not push half-baked, untested, incomplete, 

not-compiling, to-be-fixed, not-ready-to-deploy code to git
push
code i to remot
s read e wh
y to d enever
eploy the
7

Have meaningful distinguishing comments for commits
includ

e bug

or sto

ry ids

too
8

                        
Never use -­‐m  <message> flag to git commit and
                    
Follow Commit message best practices
characters or less. That is summary.
• First line is 50line
• Then a blanktext should be wrapped at 72 characters.
• Remaining description
That is detailed
9
Squash commits of your completed story into one
before pushing to upstream
we ar
inter e not int
nals o eres
f stor ted in
ies
10

Squash commits of bug fix into one and exactly one commit
that completely represents that bug fix
Half o

f bug
fix is
usele
ss
11

Never bundle logically different components
in the same commit
think

about

rolling

back

too
12

Commit often, perfect later, publish once
13

Use .gitıgnore in order not to send irrelevant files
never
packa push irr
IDE or ges, com elevant
OS re piled binar
lated files, ies,
files temp
file

s,
14

Always review code before Committing it
check
stagi what y
ng are ou se
nt to
a
15
Clean up unused and out-of-date suPpoRTing branches
and n
remotever del
e bra ete un
nches merg
ed
16

do not reset without stashing or committing & tagging
no one

want
s to l

ose co

de, uh

?
references
and good to reads
“A successful git branching model”

http://nvie.com/posts/a-successful-git-branching-model

“A git workflow for agile teams”

http://reinh.com/blog/2009/03/02/a-git-workflow-for-agile-teams.html

“merge or rebase”

http://blog.sourcetreeapp.com/2012/08/21/merge-or-rebase/

“git pull --rebase by default”

http://d.strelau.net/post/47338904/git-pull-rebase-by-default

“a rebase workflow for git”

http://www.randyfay.com/node/91

“A DEEP DIVE INTO THE MYSTERIES OF REVISION CONTROL”

http://blog.experimentalworks.net/2009/03/merge-vs-rebase-a-deep-dive-into-the-mysteries-of-revision-control
references
and good to reads
“GIT BEST Practices”

http://sethrobertson.github.io/GitBestPractices

“GIT BEST Practices: Workflow Guidelines”

http://www.lullabot.com/blog/article/git-best-practices-workflow-guidelines

“5 useful tips for a better commit message”

http://robots.thoughtbot.com/5-useful-tips-for-a-better-commit-message

“Proper git commit messages and elegant git history”

http://ablogaboutcode.com/2011/03/23/proper-git-commit-messages-and-an-elegant-git-history

“branch per feature”

http://dymitruk.com/blog/2012/02/05/branch-per-feature/

ımages

http://www.flickr.com/photos/ableman/1209643278
http://www.flickr.com/photos/ibnhusin/3883416540
http://www.flickr.com/photos/mylor/314975954/
http://www.ccjdigital.com/files/2010/08/highways.jpg
http://www.flickr.com/photos/librariesrock/4275765000
http://15pictures.com/wp-content/gallery/15-pictures-adriana-lima/adriana-lima-1.jpg
@lemiorhan
@lemiorhan
@lemiorhan
agilistanbul.com

Lemİ orhan ergİn
lemiorhan@agilistanbul.com

lemiorhanergin.com

Principal Software Engineer @ Sony
Founder & Author @ agilistanbul.com

Git and Git Workflow Models as Catalysts of Software Development

  • 1.
    GIT & GITworkflow MODELs AS CATALYSTS OF SOFTWARE DEVELOPMENT @lemiorhan Lemİ Orhan ERGİN lemiorhanergin.com @lemiorhan
  • 2.
    Lemİ Orhan Ergİn CSM,PSM1 2013 Principal Software Engineer at Sony 2001 has worked in Tüsside, BYM, GittiGidiyor/eBay and Sony as lead developer, technical leader, technical coordinator and scrum master 2009 2 2005 using Git, but not an expert agile 0.5M experienced in agile transformation and building agile culture in teams & organisations organisational level SVN to GIT migration projects experienced so far doing code reviews as a daily habit total number of views of his presentations
  • 3.
  • 4.
    I love git because… I usedSVN for a while Local branching is cheap Everything is local Distributed Ruby on Rails with full history and branches weight 13Mb.
 Small and efficient It weights 115Mb in SVN Any workflow Each object is compressed by zlib and transferred over wire Lightening Fast one by one Huge community More than 3M people˝ More than 5M repositories˝ GitHub… Thanks God! Raised $100 million on July'12
  • 5.
    git data modelis hot It is a directed acyclic graph Objects (blob, tree, commit, tag) are immutable References (branch, remote) always change
  • 6.
    Stop comparing SVNwith GIT It is not a magical version of SVN. Try to understand what it's actually doing.
  • 7.
    “ It's a stupidcontent tracker. 
 It tracks files and folders. I really really designed it coming at the problem from the viewpoint of a file system person, I actually have absolutely zero interest in creating a traditional SCM system. LINUS TOVALDS ”
  • 8.
    git changed the waywe think of merging branching workflows
  • 9.
    git is atool for designing vcs workflows
  • 10.
    main branches supporting branches Featuredevelopment release development hot fixes in production git workflow model
  • 11.
    main branches main branchesare permanent branches which are created at the very beginning and n ever d elete d!
  • 12.
    main branches OPTıONAL development It reflectsthe latest delivered development changes for the next release Automatic nightly builds test & QA STAGING & UAT MASTER Production
  • 13.
    main branches OPTıONAL development test &QA It reflects the code which is deployed to test/qa environment for testing Automatic nightly builds Automatically deployed to test/qa servers every night STAGING & UAT MASTER Production
  • 14.
    main branches OPTıONAL development test &QA STAGING & UAT It reflects the code which is deployed to staging/uat environment for testing Automatic nightly builds Automatically deployed to staging servers every night Automatically deployed to test/qa servers every night MASTER Production
  • 15.
    main branches OPTıONAL development test &QA STAGING & UAT MASTER Production It reflects the code which is deployed to production Automatic nightly builds Automatically deployed to staging servers every night Automatically deployed to test/qa servers every night Automatically deployed to production servers on demand
  • 16.
    supporting branches feature branches HOTFIXbranches release branches These have limited life time and will be removed eventually
  • 17.
    supporting branches feature branches HOTFIXbranches release branches These have specific purpose and strict rules for originating and target branches
  • 18.
    Feature development All featurebranches should be created from The development branch the n ext r eleas e bra nch
  • 19.
    Feature development take anew feature branch regardless of the feature size you ca comm n fix v in dev on issue ery mino elopm s direc r like f ent b tly ixing ranch typos ,
  • 20.
    Feature development Ne Feature 1 Feature2 2 Feature 2 is completed and ready for the next release Feature 3 xt development Rel ea se
  • 21.
    Ne Feature development Feature 1 Feature1 is being developed Feature 2 2 1 Feature 3 xt development Rel ea se
  • 22.
    Feature development Ne Feature 1 Feature2 Feature 3 xt development Rel ea se 2 1 D Feature 2 is completed and merged back to master
  • 23.
    Ne Feature development Feature 1 Feature1 gets the commits in Feature 2 Feature 2 Feature 3 development Rel ea se 2 1 D 1 xt
  • 24.
    Ne Feature development Feature 1 Pullsall the commits from other features and resolve conflicts Feature 2 Feature 3 development Rel ea se 2 1 D 1 1 xt D
  • 25.
    Feature development Ne Feature 1 Feature2 Feature 3 xt development Rel ea se 2 1 D 1 D 1 3 Feature 3 is created from development. It has commits of Feature 2
  • 26.
    Feature development Ne Feature 1 Feature2 Feature 3 xt development Rel ea se 2 1 D 1 D 1 3 D Feature 1 is completed and merged back to master
  • 27.
    Feature development Ne Feature 1 Feature2 Feature 3 development Rel ea se 2 1 D 1 D 1 3 D 3 Feature 3 gets the commits of Feature 1 xt
  • 28.
    Feature development Ne Feature 1 Feature2 Feature 3 development Rel ea se 2 1 D 1 D 1 3 D 3 3 Feature 3 pull updates frequently xt D
  • 29.
    Feature development Ne Feature 1 Feature2 Feature 3 xt development Rel ea se 2 1 D 1 D 1 3 D 3 3 D D Typo is fixed directly in development branch
  • 30.
    Feature development Ne Feature 1 Feature2 Feature 3 development Rel ea se 2 1 D 1 D 1 3 D 3 Feature 3 pulls commit about fixing the typo 3 3 xt D D
  • 31.
    Feature development Ne Feature 1 Feature2 Feature 3 xt development Rel ea se 2 1 D 1 D 1 3 D 3 3 D D 3 D Feature 3 is completed and merged back to master. It has commits of all 3 features now.
  • 32.
    release development Release branchis created when all features are ready for the next release some featu times w re fre e call eze it as
  • 33.
    release development Release branchis deleted when the release completes we w code, ill tag t branc no need he releas to ke ed h.. ep th e
  • 34.
    release development el N t ex s ea e R development F D F D Completedfeatures are merged with development release MASTER Production
  • 35.
    release development el N t ex s ea e R development F D F D D Allfeatures are ready for the next release release MASTER Production
  • 36.
  • 37.
    release development el N t ex s ea e R development release MASTER Production F D F D D R Onlyfixes are allowed R D R Bug fixes are continuously merged back to development brach D
  • 38.
  • 39.
    release development el N t ex s ea e R development release F D F D D R R D R Latestfixes are merged back to development branch D R D MASTER Production
  • 40.
  • 41.
    hot fixes inproduction Fix branches are required because every fix should be well tested and verified it me to rol ans, you done i lback w may nee n the hat yo d fix u’ve
  • 42.
    hot fixes inproduction el N t ex s ea e R development Hot-FIX MASTER Production Hot fix is required! A new branch is created from production branch M
  • 43.
    hot fixes inproduction el N t ex s ea e R development Hot-FIX MASTER Production M Fix is developed, tested and verified. Ready to go. H
  • 44.
    hot fixes inproduction el N t ex s ea e R development Hot-FIX MASTER Production M H D Hot fixes are merged back to development branch
  • 45.
    hot fixes inproduction el N t ex s ea e R development Hot-FIX MASTER Production M H Hot fix is merged with production branch and production branch is tagged D M
  • 46.
    ALL FLOWS INTHE MODEL This graphic is taken from Vincent Driessen’s article called 
 “a successful git branching model”
  • 47.
  • 48.
    1 creatE permanent branches Ifthese does not exist ➜ git:(master)  git checkout -b development Switched to a new branch 'development' ➜ git:(development)  git push origin development Total 0 (delta 0), reused 0 (delta 0) To UberProject.git  * [new branch]   development -> development ➜ git:(development)  git branch -a * development   master   remotes/origin/development   remotes/origin/master  it cre branc ates de v pushe h from m elopme s to r aste nt emot r and e
  • 49.
    2 Pull to update
 localdevelopment branch be sure you run tests directly afterwards ➜ git:(master) git fetch origin From UberProject  * [new branch]   development -> origin/development ➜ git:(master) git checkout development Branch development set up to track remote branch development from origin. Switched to a new branch ‘development' ➜ git:(development) git pull remote: Counting objects: 19, done. remote: Compressing objects: 100% (8/8), done. remote: Total 17 (delta 2), reused 0 (delta 0) Unpacking objects: 100% (17/17), done. From UberProject   3eb8b34..c827c84  development -> origin/development Updating 3eb8b34..c827c84 Fast-forward  grails-app/controllers/org/example/BookController.groovy |  6 ++++++  grails-app/domain/org/example/Book.groovy   |  7 +++++++  test/unit/org/example/BookControllerTests.groovy   | 17 +++++++++++++++++  test/unit/org/example/BookTests.groovy   | 17 +++++++++++++++++  4 files changed, 47 insertions(+)  create mode 100644 grails-app/controllers/org/example/BookController.groovy  create mode 100644 grails-app/domain/org/example/Book.groovy  create mode 100644 test/unit/org/example/BookControllerTests.groovy  create mode 100644 test/unit/org/example/BookTests.groovy 
  • 50.
    3 create a featurebranch
 from development with a name having story id and descriptive title ➜ git:(development)  git checkout -b feature-1185-add-commenting Switched to a new branch 'feature-1185-add-commenting'  ➜ git:(feature-1185-add-commenting)   the t hints itle shou about ld giv what e ’s in it
  • 51.
    4 work in yourfeature branch commit early and often Be careful! “push early it does not mean and often” ➜ git:(feature-1185-add-commenting) vi web-app/WEB-INF/applicationContext.xml ➜ git:(feature-1185-add-commenting) ✗ git add . ➜ git:(feature-1185-add-commenting) ✗ git commit -m "added comment for applicationContext.xml" [feature-1185-add-commenting b6f68cc] added comment for applicationContext.xml  1 file changed, 2 insertions(+), 1 deletion(-) ! ➜ git:(feature-1185-add-commenting) vi web-app/WEB-INF/sitemesh.xml ➜ git:(feature-1185-add-commenting) ✗ git add . ➜ git:(feature-1185-add-commenting) ✗ git commit -m "added comment for sitemesh.xml" [feature-1185-add-commenting 0e74f89] added comment for sitemesh.xml  1 file changed, 3 insertions(+), 1 deletion(-) ! ➜ git:(feature-1185-add-commenting) vi .application.properties ➜ git:(feature-1185-add-commenting) ✗ git add . ➜ git:(feature-1185-add-commenting) ✗ git commit -m "increased the application version" [feature-1185-add-commenting 7ce1f07] increased the application version  1 file changed, 1 insertion(+), 1 deletion(-)
  • 52.
    5 rebase frequently
 to incorporateupstream changes to prevent your branch from diverging significantly ➜  git:(feature-1185-add-commenting) git fetch origin development From UberProject  * branch   development -> FETCH_HEAD ➜  git:(feature-1185-add-commenting) git rebase origin/development First, rewinding head to replay your work on top of it... Fast-forwarded feature-1185-add-commenting to origin/development. 
  • 53.
    5 rebase frequently
 to incorporateupstream changes to prevent your branch from diverging significantly ➜  git:(feature-988-add-shelf-controller) git checkout development Switched to branch 'development' Your branch is behind 'origin/development' by 2 commits, and can be fast-forwarded.   (use "git pull" to update your local branch) ➜  git:(development) git pull Updating 4559eba..d55ee12 Fast-forward  application.properties   |  2 + grails-app/domain/org/example/Shelf.groovy |  7 +++++++  test/unit/org/example/ShelfTests.groovy   | 17 +++++++++++++++++  web-app/WEB-INF/applicationContext.xml   |  3 ++ web-app/WEB-INF/sitemesh.xml   |  4 +++ 5 files changed, 30 insertions(+), 3 deletions(-)  create mode 100644 grails-app/domain/org/example/Shelf.groovy  create mode 100644 test/unit/org/example/ShelfTests.groovy ➜  git:(development) git checkout feature-1185-add-commenting Switched to branch 'feature-988-add-shelf-controller' ➜  git:(feature-988-add-shelf-controller) git merge development Updating 7761c9c..d55ee12 Fast-forward  application.properties   | 2 + web-app/WEB-INF/applicationContext.xml | 3 ++ web-app/WEB-INF/sitemesh.xml   | 4 +++ 3 files changed, 6 insertions(+), 3 deletions(-)  ing th s me tep 
 e sara s onal th xt iti oes h e add mit t d wit an com i and erge m
  • 54.
    6 Interactive rebase
 to squashyour commits be sure that we only deal with the local commits ➜  git:(feature-1185-add-commenting) git rebase -i origin/development git will display an editor with a list of the commits to be modified pick 4559eba updated application version pick d1706ae added comments for applicationContext.xml pick d3c2734 added comments for sitemesh.xml Now we need to tell git what to do. keep the first one as it is and change the others as “squash” pick 4559eba updated application version squash d1706ae added comments for applicationContext.xml squash d3c2734 added comments for sitemesh.xml Git squashes the commits together to one commit and opens a new editor to enter commit message updated application version, added comments to applicationContext.xml and siteMesh.xml files Now the last 3 commits are squashed into one commit with a special commit message
  • 55.
    7 merge your changes
 withdevelopment branch It’s time to merge the completed work ➜  git:(feature-1185-add-commenting) git checkout development Switched to branch 'development' Your branch is behind 'origin/development' by 3 commits, and can be fast-forwarded.   (use "git pull" to update your local branch) ➜  git:(development) git pull Updating c827c84..7761c9c Fast-forward  application.properties   |  2 + grails-app/controllers/org/example/ShelfController.groovy |  6 ++++++  grails-app/domain/org/example/Shelf.groovy   |  7 +++++++  test/unit/org/example/ShelfControllerTests.groovy   | 17 +++++++++++++++++  test/unit/org/example/ShelfTests.groovy   | 17 +++++++++++++++++  5 files changed, 48 insertions(+), 1 deletion(-)  create mode 100644 grails-app/controllers/org/example/ShelfController.groovy  create mode 100644 grails-app/domain/org/example/Shelf.groovy  create mode 100644 test/unit/org/example/ShelfControllerTests.groovy  create mode 100644 test/unit/org/example/ShelfTests.groovy some we m one push erge, ed bef damm ore it! ➜  git:(development) git merge feature-1185-add-commenting Updating 7761c9c..d55ee12 Fast-forward  application.properties   | 2 + web-app/WEB-INF/applicationContext.xml | 3 ++ web-app/WEB-INF/sitemesh.xml   | 4 +++ 3 files changed, 6 insertions(+), 3 deletions(-)
  • 56.
    8 push your changesto the upstream ➜  git:(feature-1185-add-commenting) git push origin development Counting objects: 13, done. Delta compression using up to 4 threads. Compressing objects: 100% (7/7), done. Writing objects: 100% (7/7), 759 bytes | 0 bytes/s, done. Total 7 (delta 4), reused 0 (delta 0) To UberProject.git    7761c9c..d55ee12  development -> development 
  • 57.
    tıps forand gitbranching model efficient usage of git
  • 58.
    1 Learn git CommandLine by heart, stop using GUI GUI is to do extrem stuff ely m like m essy w erging hen y and b ou need ranch ing.
  • 59.
    2 Only few peopleshould be authorised for merging development branch to master branch for do durin ing a th g mer e last ge by revie techn w ical le ads
  • 60.
    3 check-in others codeat least once a day It’s b when etter to ever c possibheck-in le
  • 61.
    4 ensure that alltests are passing
 before pushing to upstream
  • 62.
    5 never rebase sharedcommits rebas no one e only th have e bran check ch w ed in here yet
  • 63.
    6 do not pushhalf-baked, untested, incomplete, 
 not-compiling, to-be-fixed, not-ready-to-deploy code to git push code i to remot s read e wh y to d enever eploy the
  • 64.
    7 Have meaningful distinguishingcomments for commits includ e bug or sto ry ids too
  • 65.
    8                        Never use -­‐m  <message> flag to git commit and                     Follow Commit message best practices characters or less. That is summary. • First line is 50line • Then a blanktext should be wrapped at 72 characters. • Remaining description That is detailed
  • 66.
    9 Squash commits ofyour completed story into one before pushing to upstream we ar inter e not int nals o eres f stor ted in ies
  • 67.
    10 Squash commits ofbug fix into one and exactly one commit that completely represents that bug fix Half o f bug fix is usele ss
  • 68.
    11 Never bundle logicallydifferent components in the same commit think about rolling back too
  • 69.
    12 Commit often, perfectlater, publish once
  • 70.
    13 Use .gitıgnore inorder not to send irrelevant files never packa push irr IDE or ges, com elevant OS re piled binar lated files, ies, files temp file s,
  • 71.
    14 Always review codebefore Committing it check stagi what y ng are ou se nt to a
  • 72.
    15 Clean up unusedand out-of-date suPpoRTing branches and n remotever del e bra ete un nches merg ed
  • 73.
    16 do not resetwithout stashing or committing & tagging no one want s to l ose co de, uh ?
  • 75.
    references and good toreads “A successful git branching model” http://nvie.com/posts/a-successful-git-branching-model “A git workflow for agile teams” http://reinh.com/blog/2009/03/02/a-git-workflow-for-agile-teams.html “merge or rebase” http://blog.sourcetreeapp.com/2012/08/21/merge-or-rebase/ “git pull --rebase by default” http://d.strelau.net/post/47338904/git-pull-rebase-by-default “a rebase workflow for git” http://www.randyfay.com/node/91 “A DEEP DIVE INTO THE MYSTERIES OF REVISION CONTROL” http://blog.experimentalworks.net/2009/03/merge-vs-rebase-a-deep-dive-into-the-mysteries-of-revision-control
  • 76.
    references and good toreads “GIT BEST Practices” http://sethrobertson.github.io/GitBestPractices “GIT BEST Practices: Workflow Guidelines” http://www.lullabot.com/blog/article/git-best-practices-workflow-guidelines “5 useful tips for a better commit message” http://robots.thoughtbot.com/5-useful-tips-for-a-better-commit-message “Proper git commit messages and elegant git history” http://ablogaboutcode.com/2011/03/23/proper-git-commit-messages-and-an-elegant-git-history “branch per feature” http://dymitruk.com/blog/2012/02/05/branch-per-feature/ ımages http://www.flickr.com/photos/ableman/1209643278 http://www.flickr.com/photos/ibnhusin/3883416540 http://www.flickr.com/photos/mylor/314975954/ http://www.ccjdigital.com/files/2010/08/highways.jpg http://www.flickr.com/photos/librariesrock/4275765000 http://15pictures.com/wp-content/gallery/15-pictures-adriana-lima/adriana-lima-1.jpg
  • 77.