Sunday, January 22, 2017

Using GitHub on Visual Studio Code


GitHub

Well known online Repository, commonly used for open source projects. Which has Source code view, Web editing (even TFS does not support this), Wiki and defect tracking system. There are couple of most commonly used flow for production roll out.


Git Commands

These are some of commands commonly used in GitHub. Most commands are integrated with Visual Code itself.
  • Fork
  • Origin
  • Checkout
  • Fetch
  • Pull
  • Push
  • Merge
  • MergeTool
  • PullRequest

Fork, is to create a personal branch
Command: git fork https://github.com/<<orgnization>>/<<project>>.git
GitHub UI:   Click on Fork button on a repository, which will prompt “Where should we fork this repository” with profile and repository. Click username or profile to create personal branch. If there is fork available for the profile it will display personal branch and the repository branch.

Set Origin, is to set working directory for development
Command: git remote add origin https://github.com/<<organization>>/<<project>>.git

Pull, to get latest version from a branch
Command: git checkout –q
-q is to keep quite on
checkout git fetch
git pull

Push, to push changes to remote from local
Command: git commit –all –m
--all – is used to take all the changes or developer can specify a file name
-m is the description for the commit change
– f is to set commit description on a file git push

Merge, if there is no conflict on check-in git merge will be able to merge all changes between branches. If there is any conflict, we have to fix those conflict and push it again. Git Hub doesn’t have any UI merging tool to fix a conflict, GitHub appends the conflict with arrow notation which highlights what came-in and what was checked-in. From this developer can fix them manually. There are lots of merge tools available in market like kdiff3, IntelliJ IDEA and lot more.
Visual Studio can also be used a merge tool. Unfortunately Visual Studio Code does not support merging.

We can use Visual Studio 2015 to do merging in UI. Once conflicts are resolved locally, perform push command to push the changes to remote, which helps merge fork/branch to desired branch.


How to set Visual Studio 2015 as merge tool?

  • Open VS 2015, install GitHub Extension
  • Open Team Explore, Click on Settings
  • Click on Global Settings to define
    • User Name 
    • Email Address 
    • Merge Tool

    Or do the changes in Git .gitconfig file by adding these lines

    [user]
    name = xxx
    email = xxxx@xxx.xxx
    [merge]
    tool = vsdiffmerge
    [mergetool]
    prompt = true
    [mergetool "vsdiffmerge"]
    cmd = \"C:\\Program Files (x86)\\Microsoft Visual Studio 14.0\\Common7\\IDE\\vsdiffmerge.exe\" \"$REMOTE\" \"$LOCAL\" \"$BASE\" \"$MERGED\" //m trustexitcode = true
    [mergetool "vsdiffmerge"]
    keepbackup = false
    [diff]
    tool = vsdiffmerge
    [difftool]
    prompt = true
    [difftool "vsdiffmerge"]
    cmd = \"C:\\Program Files (x86)\\Microsoft Visual Studio 14.0\\Common7\\IDE\\vsdiffmerge.exe\" \"$LOCAL\" \"$REMOTE\" //t
    [difftool "vsdiffmerge"]
    keepbackup = false

    User name and email are defined which can be used as a default attributes for git commit and git push



    Setting up Development Environment using Visual Studio Code

    • Visual Studio Code by default supports GitHub integration
    • Fork a branch
    • Create a folder in local path, open the folder in Visual Studio Code and Initialize GitHub

    • Execute git origin to set working directory (Use personal branch instead of remote branch)
    • Reopen Visual Studio Code by default VS Code will be opened with master branch in VS Code which will be displayed on Task bar.
    • Click “master” Git Icon from task bar, which helps to checkout a branch to local folder.
    • Click “sync” on git repository to get latest version from remote.


    Check-in changes

    • After making necessary changes click on Git which show changes performed.
    • Click on Tick mark which help commit changes with label for the changes
    • Click on “sync” icon or push link from "..." icon to push and pull changes to remote.


    How to merge conflicts on pull request

    • Open folder from which check-in is performed.
    • Open command prompt (Please do not use Visual Studio Code for executing this as merge tool. Launch is not supported from VS Code)
    • Pull repository files from where conflict is happening, for e.g.,
    • git pull https://github.com/<<organization&gt&gt/<<project>>.git <<branch>>
    • On completion of pull request, conflicts will be available in working folder.
    • Execute merge, “git mergetool” which will launch for Visual Studio 2015 to resolve conflict.
    • Execute push, “git push” which will push the changes to remote.


    This will help to fix merge conflict on a pull request from personal branch or a branch to desired branch.


    Development Process in GitHub

    GitHub flow

    In this flow Master Branch, which always act as a production branch that keeps the production copy always. Feature Branch for the development branch There are two ways of committing changes.

    • Check-in without any code review (Most people doesn’t prefer for this)
      • Make necessary changes on branch
    • Check-in with code review, forking or branching is required before merging. This is done by protecting a branch
      • Branching is not recommended, as everyone can be able to see the branch and any one can check-in on the branch
      • Fork is a personal branch which will be visible only to you.
      • Make necessary changes on your fork.
    • Commit Changes
    • Pull Request, If code changes is done in personal branch, merge changes to feature branch
    • Once a branch is ready to be deployed, deploy the branch, if there is any issue in production then rollback production with master, and else merge branch changes to master. 
    • For more information: https://guides.github.com/introduction/flow/


    Git Flow

    In this flow there will be set of physical branch like

    • Master(Production Branch)
    • Development Branch
    • Feature Branch
    • Release Branch
    • Hot Fix Branch
    This flow is most commonly used in enterprise application development. Install “Gitflow/Git-flow-cheatsheet” application which will provide high level operation for Vincent Driessen's branching model. Create required set of Physical branches.

    How this works

    • Development is done at Development and Feature Branch
    • Once testing is done on a development/feature branch, source code will be merged to release branch.
    • Release ready validation is performed on release branch.
    • Changes on release branch will be merged into development branch.
    • Once release branch is ready to be deployed, deploy the release branch in production.
    • Merge Release branch with hotfix, if there is any issue in production, then rollback change with master.
    • If there is any issue in production after rollout, do the changes in hotfix branch and move changes to production from hotfix.
    • Merge changes from hotfix to development and release branch.
    • Once hotfix branch is stable, changes will be merged to master.
    • For more information https://github.com/nvie/gitflow http://danielkummer.github.io/git-flow-cheatsheet/


    Protect GitHub Branch

    • Open GitHub
    • Select Repository for which protection is to be defined.
    • Select Settings
    • Select Branches
    • In Protected Branches, select a branch to which protection is to be defined.
    • Check "Protect this branch", which helps to define protection policy for the branch
    • Require pull request review before merging 
    • Restrict the list of user can merge the changes 
    • Require status check, this can help to check status from external service before merge.
    • Enterprise edition Protection options
    • Open Source edition Protection options