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Sungkyunkwan University

Tizen/Artik IoT Practice Part 4Open Source Development

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• SCM Tool: Git

– Version Management

– Local & Remote Repository

– Branch Management

• Github Contribution Process

– Issue

– Fork Project

– Pull Request

Contents

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• Working directory– Source code in work– “add” command: adds files/directories to staging

area

• Staging area(index)– Source code to be committed– “commit” command: makes a new version in

repository

• Repository(HEAD)– Source code already committed– Files or directories are stored as content-

addressable objects identifiable by hash value.

Git: Key Concepts

Working Directory

hello.c hello.h

(Local) Repository

Staging Area

Ver.1

hello.h

Ver.2

hello.c hello.h

Commit

Add

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• Add a source code, ‘hello.cpp’1. Add hello.c to staging area

1. $ git add hello.c

2. Make a new version1. $ git commit -m “commit message”

• Add all of the source code1. Add all of the source code

1. $ git add --all

2. Make a new version1. $ git commit -m “commit message”

• Display staging area’s status1. $ git status

Git: Version Management (1/2)

Working Directory

hello.c hello.h

(Local) Repository

Staging Area

Ver.1

hello.h

Ver.2

hello.c hello.h

Commit

Add

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• Display the commit log

1. $ git log

– Each commit’s hash value, author information, date, message

Git: Version Management (2/2)

Working Directory

hello.c hello.h

(Local) Repository

Staging Area

Ver.1

hello.h

Ver.2

hello.c hello.h

Commit

Addcommit 783c82ff64eda9f03401834de906eca77d01f691Author: Gyeonghwan Hong <redcarrottt@gmail.com>Date: Mon Sep 22 10:37:44 2014 +0900

2nd version commit: hello.c is added

commit 712943bb31bf85430e1a027abe197e5b88a26110Author: Gyeonghwan Hong <redcarrottt@gmail.com>Date: Thu Aug 28 12:08:17 2014 +0900

1st version commit: hello.h is added

• Return to a previous version

1. git checkout <commit’s hash value>ex. git checkout 712943bb31bf85430e1a027abe197e5b88a26110

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• “Commit”

– Make a new version on local repository

Git: Local & Remote Repository (1/2)

• “Push”

– Upload commits in local repository to remote repository

• “Pull”

– Download commits in remote repository to local repository

Local PC

Working Directory

hello.c hello.h

(Local) Repository

Staging Area

Ver.1

hello.h

Ver.2

hello.c hello.h

Github Server (Remote)

(Remote) Repository

Ver.1

hello.h

Ver.2

hello.c hello.h

Pull

Push

Commit

Add

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• Upload to remote repository

1. $ git push <remote name> <remote branch>

– ex. $ git push origin master

• Download from remote repository

1. $ git pull

Git: Local & Remote Repository (2/2)

Local PC

Working Directory

hello.c hello.h

(Local) Repository

Staging Area

Ver.1

hello.h

Ver.2

hello.c hello.h

Github Server (Remote)

(Remote) Repository

Ver.1

hello.h

Ver.2

hello.c hello.h

Pull

Push

Commit

Add

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• Check the branch list of local repository

1. $ git branch --list

• Check the branch list of remote repository

1. $ git branch --remote

• Move to another branch

1. $ git checkout <branch name>

– ex. $ git checkout feature_x

Git: Branch Management (1/3)

* masterfeature_x

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• Develop a new feature by making a new branch

1. Make a new branch ‘feature_x’

1. $ git branch feature_x

2. $ git checkout feature_x

2. Edit and commit source code

Git: Branch Management (2/3)

3. Merge ‘feature_x’ branch to original branch

1. $ git checkout master

2. $ git merge feature_x

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• Conflict– When merging feature_y branch to master branch, ‘hello.h’ in

version 2-x and 2-y have different changes each other.

– This situation is called as ‘conflict’.

– The conflict should be resolved by ‘conflict resolution’ process.1. $ git mergetool

Git: Branch Management (3/3)

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• Issue

– Suggestion of new feature, bug fix, enhancement in Github community

– After discussion on the issue with project’s collaborators, project’s direction is determined

• Assign an Issue

– Project collaborators can assign an issue to specific developers.

Github Contribution: 1. Issue

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• Fork Project

– In order to contribute to Project, fork the Github repository to the own repository, then start to implement the new feature.

Github Contribution: 2. Fork Project

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• Fork Project

– Option 1. Clone forked project onto local PC

• $ git clone https://github.com/<your ID>/<repository name>

– Option 2. Add a remote server

• $ git remote add <server name> https://github.com/<your ID>/<repository name>

• $ git pull <server name> <branch name>

Github Contribution: 2. Fork Project

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• Pull Request

– Click “New pull request” button, then create pull request message

Github Contribution: 3. Pull Request

– After the review and vote of maintainers, the pull request is determined to be merged or rejected.