Basics

setup git

• in a project dir

mkdir example_repo                             create repo directory
git init                                       initialize local git repo, creates .git folder
git config --global user.name 'John Doe'
git config --global user.email 'jdoe@email.com'

create .gitignore

• make sure you set up .gitignore before git add

vim .gitignore

   log.txt
   /dir1
   *.RMarkdown

git add, rm, commit, status

git add file1 file2                add files to index/staging area before committing
git add file3 ...
git add *.html                     add all .html files to staging area
git add .                          add all files to staging area
git rm --cached file3              remove file from staging area

git status                         check status of working tree (what files added, modified, unmodified)
git commit                         commit files in staging area
git commit -m 'changed something'  to add comment to commit

create branches

git branch somebranch                    add a branch
git checkout somebranch                  goes into a branch

    - create/edit some files
    - commit them

git checkout master                      goes into master branch

git merge somebranch                     while in master branch, merge somebranch
git merge somebranch -m 'some message'   to write a commit message

working with GitHub

• create new repo on GitHub

git remote                               # to view remote repos
git remote add origin https://github.com/username/repo
git remote remove origin
git remote -v

git push -u origin master                # to push master to remote repo
# github login window will open to authenticate for the first time

• reload GitHub page and local repo should be there

git pull <url>        # pulls latest version from remote repo
git clone <url>       # copies a remote repo into current dir

git reset

• to restore previous commits

git reflog
f322517 (HEAD -> master) HEAD@{0}: reset: moving to HEAD
f322517 (HEAD -> master) HEAD@{1}: pull https://github.com/username/repo.git: Merge made by the 'recursive' strategy.
9a71bf1 HEAD@{2}: commit: updated gitignore
36340f8 (origin/master) HEAD@{3}: commit: updated gitignore
5f98d77 HEAD@{4}: commit (initial): initial commit

git reset --hard 5f98d77
HEAD is now at 5f98d77 website initial commit

• lesson: add files to .gitignore before initial commit
• lesson: do not delete files on github, do everything with git

misc

• create SSH keys so no need to login to github every time

EOF