git

Thursday, May 23, 13

and why learn it first?what is git?

Thursday, May 23, 13

GIT HELPS US...

•track & undo changes (manage versions)

•collaborate on projects

•share code with others

Thursday, May 23, 13

HOW DOES IT WORK?

•we create a git repository for a given project• this is a folder containing the project, and its entire history

• the history is stored as snapshots (called commits)

•the folder generally contains the latest version• this is called the working directory

•we interact with git using the git command

Thursday, May 23, 13

HOW DOES IT WORK?•git only tracks the files we tell it to

• to track a file, we use git add filename

•each time we want to create a ‘savepoint’, we create a commit

•git only commits the changes we tell it to• to add a modified file to a commit, use git add filename

• this adds changes to the staging area

•to create a commit, use git commit -m “commit message”

Thursday, May 23, 13

Thursday, May 23, 13

GIT DEMO

git  config  -­‐-­‐global  user.name  "Adam  Bray”git  config  -­‐-­‐global  user.email  "adam.bray@yale.edu”

Thursday, May 23, 13

GIT DEMO

#  setup  vagrantcd  ~/path/to/your/codemkdir  assignment3vagrant  init  railsvagrant  upvagrant  ssh

Thursday, May 23, 13

GIT DEMO

#  change  dir  to  shared  foldercd  /vagrant  

mkdir  git-­‐demogit  initgit  status

Thursday, May 23, 13

GIT DEMO

touch  hello.rbsubl  .git  statusgit  add  hello.rbgit  commit  -­‐m  “created  hello  program”git  statusgit  log

Thursday, May 23, 13

GIT DEMO

touch  bye.rbgit  statusgit  add  bye.rbgit  commit  -­‐m  “added  bye  program”git  statusgit  log

Thursday, May 23, 13

github

Thursday, May 23, 13

Thursday, May 23, 13

CREATING A REPO ON GITHUB

•Login to github.com

•create a repository called git-demo

•follow instructions under “Push an existing repository from the command line”

Thursday, May 23, 13

COMMON GITHUB WORKFLOW

#make  some  changes  to  filesgit  statusgit  add  .git  commit  -­‐m  “description  of  changes”#make  more  changes  and  repeat

git  pull  #check  for  conflictsgit  push  #send  changes  to  github

Thursday, May 23, 13

CLONING A REPO

To  download  a  repo  for  the  first  time,  use:

git  clone  https://github.com/intro-­‐to-­‐rails-­‐course-­‐yale/git-­‐demo.git

Thursday, May 23, 13

TIPS

•Commit often

•Commits should contain only related changes

•Don’t commit half-baked features

Thursday, May 23, 13

SUMMARY

•git init #create a git repo

•git add filename #add file(s) to be committed

•git commit -m “message” #create a commit (savepoint)

•git pull / git push #get / send changes to github

•git status #check status of repo

•git log #look at commit history

Thursday, May 23, 13