Git

View the changes you made to dtl.py in the current directory.

git diff dtl.py
git diff HEAD~ HEAD	# View all changes of the most recent commit

Check the changes you’ve made after last update.
```
git status
```
Stage all changes made to the files in the data folder.
```
git add data/*
```
Stage all the changes
```
git add -A
git add --all
```

Stage deleted files for commit

git add -u
git rm $(git ls-files --deleted)
git status | grep 'deleted:' | cut -d':' -f2 | xargs -t -I {} git add -u "{}"

With remote repository specified, download the latest objects and refs from the remote.
```
git fetch
```
Check the history of commits from all the developers.
```
git log
```
Download the latest changes to the local repository.
```
git pull
```
On your local, create a new branch called “my-branch” for your future development.
```
git checkout -b my-branch
```
Merge changes in master branch to feature branch. ```bash git checkout feature-branch git merge master

git merge -s ours master # To always keep the changes from the feature-branch

- Remove dtl.py from the added files.
```bash
git reset HEAD dtl.py	# remove last commit, keep the changes

git reset --hard HEAD^	# remove last commit, discard changes

Commit the changes you have added with the label “Test program and raw data”.
```
git commit -m "Test program and raw data"
```
Push the committed changes to remote.
```
git push
git push origin <branch-name>
```
Push a new local branch to a remote Git repository
```
git push -u origin <feature-branch-name>
```
Check all the available tags of the project.
```
git tags
```
Check the current tag of the project.
```
git describe --tags
```
Clone the repository called “project” with tag “v0.0.3” to your local via this link: git@gitlab.dtl:user/project.git
```
git clone git@gitlab.dtl:user/project.git project.0.0.3
```

Clone the repository using one’s personal access token

git clone https://oauth-key-goes-here@github.com/username/repo.git

Clone and update submodule

git submodule init
git submodule update

Check out to a specific tag
```
git checkout <tag-name>
```

Merge changes from feature branch to master branch

git checkout master
git pull origin master
git merge feature-branch
git push origin master

Get url of remote repository
```
git remote -v
```

Set up git credentials for Vertex AI notebook

mkdir ~/.ssh/
cp id_ed25519* ~/.ssh/
cd ~/.ssh/
chmod 600 id_ed25519
git config --global user.email "shenghao.wang@gojek.com"

Migrate repo from BitBucket to GitHub

git clone https://Shenghao1993@bitbucket.org/Shenghao1993/coursera-introduction-to-data-science-in-python.git
git remote add upstream https://github.com/shenghaowang/udacity-ai-for-trading-nanodegree.git
git remote -v
git remote set-url origin git@github.com:shenghaowang/udacity-ai-for-trading-nanodegree.git
git push -u origin master

Set up ssh to access remote site without password
1. Generate private and public keys on the local machine by running ssh-keygen.
2. Copy the public key.
3. Go to the remote site. Under the directory ~/.ssh, create a text file called “authorized_keys” if it doesn’t exist.
4. Paste the public key into the file.
5. Shortcut: ssh-copy-id -i ~/.ssh/id_rsa.pub mahwah-dtltrad3 (Send generated public key from car8 to mw3)

Copy public key of one machine to another machine

$ ssh-copy-id -i ~/.ssh/dat_prod1.pub dtl-data01

Check the email address linked with repos ```bash git config –global user.email # for all repos on the computer

git config user.email # for a single repo

- Set email address linked with repos
```bash
git config --global user.email <email-address>	# for all repos on the computer

git config user.email <email-address>	# for a single repo

To fix the git push error: Unable to append to .git/logs/refs/remotes/origin/master: Permission denied. The owner and group might be set to root.

sudo chown -R "${USER:-$(id -un)}" .	# run this from the root of the git working tree

sudo chgrp {user} .git/logs/refs/remotes/origin/master
sudo chown {user} .git/logs/refs/remotes/origin/master

To fix the git push error: insufficient permission for adding an object to repository database
```
sudo chown -R "${USER:-$(id -un)}" .
```

Delete a feature branch from both local and remote

git checkout master
git branch -D <feature-branch>
git push origin --delete <feature-branch>
git branch --all

Create a branch out of an existing branch

git checkout old_branch
git branch new_branch

git checkout -b new_branch old_branch

Rename a git branch ```bash git branch -m # To rename the current branch

git branch -m # To rename a branch while pointed to any branch

git push origin -u # To push the local branch and reset the upstream branch

git push origin –delete # To delete the remote branch

- Release a new version
```bash
git checkout master + git pull
git checkout staging + git pull
git checkout -b release-xxx
git merge master + resolve merge conflicts
git push origin release-xxx
# Create 2 MRs (1 for merging to staging, 1 for merging to master) using the release template.