The GitLab CI/CD pipeline for the “Squid squid-7.3” project consists of multiple stages. This document provides an in-depth analysis of these stages and their corresponding jobs in the pipeline.
The hadolint job falls under the Quality stage. The quality of the Dockerfile is checked using hadolint, a Dockerfile linter that helps to catch common mistakes and security issues.
hadolint:
image: hadolint/hadolint:latest-debian
stage: Quality
before_script:
- cd $CI_PROJECT_DIR
script:
- hadolint --ignore DL3008 Dockerfile image: hadolint/hadolint:latest-debian This line
specifies the docker image that is going to be used for this job. In
this case, it’s the Dockerfile linter, hadolint.before_script: - cd $CI_PROJECT_DIR Before the script
executes, the CI/CD changes the directory to the project directory.script: - hadolint --ignore DL3008 Dockerfile This
command runs hadolint on the Dockerfile, ignoring the DL3008 rule.The getsquid_vars job belongs to the Get-version stage and is responsible for getting the latest version of Squid from GitHub, updating the README.md file and then pushing the updated README.md back to the master branch.
getsquid_vars:
stage: Get-version
image:
name: $CONTAINER_CLIENT_IMAGE
artifacts:
expire_in: 1 hour
paths:
- variables.env
script:
- apt update && apt install git curl ca-certificates -y --no-upgrade --no-install-recommends --no-install-suggests
- export SQUID_VERSION=$(curl -LsXGET https://github.com/squid-cache/squid/releases/latest | grep -m 1 "Release" | cut -d " " -f4 |tr -d 'v')
- echo "SQUID_VERSION=$SQUID_VERSION" > variables.env
# the rest of the scriptThe script starts by updating the Apt package list and installing the
necessary packages. Then it defines the variable SQUID_VERSION by
pulling the latest Squid version from GitHub. This version number is
then written to the variables.env file.
This job is responsible for building the Docker image in the Docker-hub-build stage. This Docker image is built using the Dockerfile and then pushed to the Docker Hub registry.
docker-hub-build:
stage: Docker-hub-build
image: docker:dind
needs:
- getsquid_vars
artifacts:
expire_in: 2 hours
paths:
- $CI_PROJECT_DIR
# the rest of the fileThe docker:dind is the Docker in Docker image that
allows Docker commands to be run inside a GitLab CI job. This job needs
the output from the getsquid_vars job which is downloaded
by GitLab CI before the job starts. Also, it has an
artifacts block which instructs GitLab CI to keep the files
specified in the paths array for two hours after the job
finishes.
The rest of the docker-hub-build job involves logging
into Docker Hub
(docker login -u "$DOCKER_HUB_USER" -p "$DOCKER_HUB_TOKEN" $DOCKER_HUB_REGISTRY),
building the Docker image
(docker build --build-arg SQUID_VERSION=$SQUID_VERSION --pull -t $CONTAINER_BUILD_NOPROD_NAME_AMD64 .)
and then pushing the Docker image to Docker Hub
(docker push $CONTAINER_BUILD_NOPROD_NAME_AMD64).
After the Docker image has been built and pushed to Docker Hub in the ‘docker-hub-build’ phase, it is then tested in the Docker-hub-test phase.
docker-hub-test:
stage: Docker-hub-test
extends: .services-amd64
before_script:
- apt update && apt install -y curl --no-upgrade --no-install-recommends --no-install-suggests
script:
- export https_proxy=http://$CONTAINER_TEST_NAME:3128 && curl -k https://www.google.fr
variables:
HOSTNAME: squidpipeline
needs: ["docker-hub-build"]In this job, CURL is used to test if the website can be reached
through the proxy deployed by the Docker image. As a dependency, it
needs docker-hub-build to be completed.
If the Docker image passes the test in docker-hub-test, it moves to the Docker-hub-pushtag stage where it is tagged and pushed to Docker Hub.
push-docker-hub:
stage: Docker-hub-pushtag
image: docker:dind
needs:
- docker-hub-test
- getsquid_vars
before_script:
- docker login -u "$DOCKER_HUB_USER" -p "$DOCKER_HUB_TOKEN" $DOCKER_HUB_REGISTRY
# the rest of the fileThe initial part of the job requires the test result from the
previous stage docker-hub-test and variable declarations
from getsquid_vars. If all dependencies are clear, it logs
into Docker Hub and the remaining part of the file includes pulling the
Docker image from Docker Hub, tagging it with different tags, and
finally pushing back the tagged images to Docker Hub.
The chatgpt_analysis job falls under the Docs stage. This job is designed to provide an analysis of the order of jobs in the GitLab CI/CD pipeline and updating html while transferring the explanation in markdown format.
chatgpt_analysis:
stage: Docs
image:
name: $CONTAINER_CLIENT_IMAGE
artifacts:
expire_in: 1 month
paths:
- $CI_PROJECT_DIR/chatgpt_analysis*
needs:
- getsquid_vars
- docker-hub-test
- docker-hub-test-arm
before_script:
- apt update && apt install curl git jq ca-certificates pandoc openssh-client -y --no-upgrade --no-install-recommends --no-install-suggests
- source variables.env
# rest of the script The first command is to update and install the necessary packages in the Docker image. The main part of the job involves running commands and scripts to generate an analysis content and making formatting changes for clarity.
There are two types of variables being used throughout these jobs: predefined and custom variables.
$CI_PROJECT_DIR, $CI_COMMIT_BRANCH,
$DOCKER_HUB_USER, $DOCKER_HUB_TOKEN ,
$DOCKER_HUB_REGISTRY, $DOCKER_HUB_PASSWORD,
$HUB_REGISTRY_IMAGE, and $GITLAB_TOKEN are
predefined GitLab CI variables or encrypted variables that are stored by
GitLab and Docker Hub.source variables.env. The SQUID_VERSION
variable, created by the getsquid_vars job, is stored in
the variables.env file and is used by many jobs. There’s
also CONTAINER_BUILD_NOPROD_NAME_AMD64,
CONTAINER_BUILD_NOPROD_NAME_ARM,
CHATGPT_API_KEY, and SSH_NOSTROMO_KEY.Files like variables.env, Dockerfile, and
READMD.md play important roles in the pipeline.
variables.env is used to store and pass important variables
between jobs. Dockerfile is the core of the Docker build
job, containing instructions on how to build the Docker image. The
README.md file is updated with the latest Squid
version.
The pipeline is executed in the order of the stages specified. The
needs keyword is used to express direct dependencies
between jobs. For instance, the docker-hub-build job needs
getsquid_vars. This means, docker-hub-build
will not start until getsquid_vars is completed.
The output of each job varies based on the operation performed in them. However, most of the jobs are centered around Docker operations. So the expected outcomes will be Docker images that are built, tested, tagged, and pushed to Docker Hub.
The pipeline also generates several artifacts. After the Docker image is built and pushed to Docker Hub, the Dockerfile (as an artifact) is stored for future reference or for a quick check after the pipeline completes successfully.
Another important artifact is the variables.env file.
This file is created in the getsquid_vars job and is passed
between jobs as an artifact so that the SQUID version can be easily
accessed by all jobs.
The latest commit in the GitLab repo updates README.md with the
latest squid version, which would be used throughout the pipeline for
the building, testing and tagging of Docker images. Since the commit
message includes [skip ci], it means this commit triggers
no pipeline. That is, changes made in this commit do not trigger any CI
builds.
Each job in the pipeline plays a specific role in the overall process. It starts with defining the new version of squid, then building and testing the Docker image. After the image passes the test, it is then tagged and pushed to Docker Hub.