# Hands-On - Some use cases with Gitlab CI/CD

These exercises will make you realize some interesting use cases with Gitlab CI/CD (I hope).

## Creating your repo

If you don't have a repo with a source code created, feel free to access https://labrei.dsce.fee.unicamp.br:6498/ninalg/gitlab-training/

You can clone this repository, or you can fork it in the gitlab web.

## Adding the .gitlab-ci.yml

Using the gitlab Web IDE or the common way to interact with gitlab (git add, commit, push), create the .gitlab-ci.yml in your repository using the code below:

default:
  image: "python:3.8"

variables:
  GIT_SSL_NO_VERIFY: "true"
    
stages:
  - build
  - test
  - deploy

build:
  stage: build
  tags:
    - carlos
  script:
    - echo "this is building"
    - python3.8 setup.py develop

  
unittest:
  tags:
    - carlos
  stage: test
  script:
    - python3.8 -m unittest discover -s app_labrei/tests/unit/

   
integration:
  tags:
    - alexandre
  stage: test
  script:
    - python3.8 setup.py develop
    - python3.8 -m unittest discover -s app_labrei/tests/integration/

    
linting:
  stage: test
  tags:
    - alexandre
  script:
    - pip install flake8
    - flake8 --ignore E305 --exclude .git,__pycache__ --max-line-length=90 app_labrei/tests/integration/
  dependencies: []


pages:
  when: always
  stage: deploy
  tags:
    - carlos
  script:
    - pip install sphinx sphinx-rtd-theme
    - cd docs/ && make html && cd -
    - mkdir .public       
    - cp -R docs/build/html .public
    - mv .public public
  artifacts:
    expire_in: 1 day
    paths:
      - public
  only:
    - master

Check if the gitlab pipeline run ok.

## Adding the Dockerfile

In the root dir of your repository, create a file name Dockerfile and fill it with the content below. Commit and push.

FROM python:3.8

RUN mkdir /app/
COPY Dockerfile /app/
COPY README.md /app/
COPY setup.py /app/
RUN ls /app/
RUN mkdir /app/app_labrei/
RUN ls /app/app_labrei/
COPY ./app_labrei/* /app/app_labrei/

WORKDIR /app

RUN python3.8 setup.py install

## Adding the Dockerfile build job to CI/CD

In the added .gitlab-ci.yml add the following code. It will trigger the execution of a job to run the construction of your docker image using the previously provided Dockerfile.

build_image:
  stage: build
  tags:
    - davi
  image: docker:19.03.12
  stage: build
  script:
    - echo "this is building docker"
    - docker build -t app_labrei:latest .

## Pushing the image to a registry

In the added .gitlab-ci.yml add the following code. It will trigger the execution of a job to build the docker image of your code, login in the configured docker registry of your choice and push the image to it.

To login in docker registry, tag and push the image, you need to configure some variables in your repository.

There are many predefined variables in gitlab CI/CD that you can use to tag your image. Check them at https://docs.gitlab.com/ee/ci/variables/predefined_variables.html.

But mostly important, you need to configure extra variables in the CI/CD part of your repository.
You must add variables for:
1. CI_REGISTRY_USERNAME: The username that you use to login in gitlab
2. CI_REGISTRY_PASSWD: The username password that you use to login in gitlab
3. CI_REGISTRY: The registry address, i.e., the place where the image is going to be stored. In our case, define this value as 10.0.1.16:5000

release:
  stage: deploy
  tags:
    - davi
  image: docker:19.03.12
  variables:
    IMAGE_TAG: $CI_REGISTRY/$CI_REGISTRY_USERNAME/$CI_PROJECT_NAME:$CI_COMMIT_REF_SLUG
  script:
    - docker login -u $CI_REGISTRY_USERNAME -p $CI_REGISTRY_PASSWD $CI_REGISTRY
    - docker build -t $IMAGE_TAG .
    - docker push $IMAGE_TAG

## Playing with the .gitlab-ci.yml

https://docs.gitlab.com/ee/ci/merge_request_pipelines/

https://docs.gitlab.com/ee/ci/yaml/README.html#onlyexcept-basic

https://docs.gitlab.com/ee/ci/yaml/README.html#when

# Final Remarks

## How to change the current folder to a new repository

### Option 1

git remote set-url origin new-repository-url

git remove -v

git push -u origin master

### Option 2

Clone the new repository in another folder, copy the content of the old folder to it, then:

git add -A

git commit -a -m "initial commit"

git push