debian-mirror-gitlab/doc/topics/autodevops/index.md
2018-03-27 19:54:05 +05:30

28 KiB

Auto DevOps

DANGER: Auto DevOps is currently in Beta and not recommended for production use.

Introduced in GitLab 10.0.

Auto DevOps automatically detects, builds, tests, deploys, and monitors your applications.

Overview

With Auto DevOps, the software development process becomes easier to set up as every project can have a complete workflow from build to deploy and monitoring, with minimal to zero configuration.

Comprised of a set of stages, Auto DevOps brings these best practices to your project in an easy and automatic way:

  1. Auto Build
  2. Auto Test
  3. Auto Code Quality
  4. Auto SAST (Static Application Security Testing)
  5. Auto SAST for Docker images
  6. Auto Review Apps
  7. Auto DAST (Dynamic Application Security Testing)
  8. Auto Deploy
  9. Auto Browser Performance Testing
  10. Auto Monitoring

As Auto DevOps relies on many different components, it's good to have a basic knowledge of the following:

Auto DevOps provides great defaults for all the stages; you can, however, customize almost everything to your needs.

For an overview on the creation of Auto DevOps, read the blog post From 2/3 of the Self-Hosted Git Market, to the Next-Generation CI System, to Auto DevOps.

Prerequisites

TIP: Tip: For self-hosted installations, the easiest way to make use of Auto DevOps is to install GitLab inside a Kubernetes cluster using the GitLab Omnibus Helm Chart which automatically installs and configures everything you need!

To make full use of Auto DevOps, you will need:

  1. GitLab Runner (needed for all stages) - Your Runner needs to be configured to be able to run Docker. Generally this means using the Docker or Kubernetes executor, with privileged mode enabled. The Runners do not need to be installed in the Kubernetes cluster, but the Kubernetes executor is easy to use and is automatically autoscaling. Docker-based Runners can be configured to autoscale as well, using Docker Machine. Runners should be registered as shared Runners for the entire GitLab instance, or specific Runners that are assigned to specific projects.
  2. Base domain (needed for Auto Review Apps and Auto Deploy) - You will need a domain configured with wildcard DNS which is gonna be used by all of your Auto DevOps applications. Read the specifics.
  3. Kubernetes (needed for Auto Review Apps, Auto Deploy, and Auto Monitoring) - To enable deployments, you will need Kubernetes 1.5+. You need a Kubernetes cluster for the project, or a Kubernetes default service template for the entire GitLab installation.
    1. A load balancer - You can use NGINX ingress by deploying it to your Kubernetes cluster using the nginx-ingress Helm chart.
    2. Wildcard TLS termination - You can deploy the kube-lego Helm chart to your Kubernetes cluster to automatically issue certificates for your domains using Let's Encrypt.
  4. Prometheus (needed for Auto Monitoring) - To enable Auto Monitoring, you will need Prometheus installed somewhere (inside or outside your cluster) and configured to scrape your Kubernetes cluster. To get response metrics (in addition to system metrics), you need to configure Prometheus to monitor NGINX. The Prometheus service integration needs to be enabled for the project, or enabled as a default service template for the entire GitLab installation.

NOTE: Note: If you do not have Kubernetes or Prometheus installed, then Auto Review Apps, Auto Deploy, and Auto Monitoring will be silently skipped.

Auto DevOps base domain

The Auto DevOps base domain is required if you want to make use of Auto Review Apps and Auto Deploy. It is defined either under the project's CI/CD settings while enabling Auto DevOps or in instance-wide settings in the CI/CD section. It can also be set at the project or group level as a variable, AUTO_DEVOPS_DOMAIN.

A wildcard DNS A record matching the base domain is required, for example, given a base domain of example.com, you'd need a DNS entry like:

*.example.com   3600     A     1.2.3.4

where example.com is the domain name under which the deployed apps will be served, and 1.2.3.4 is the IP address of your load balancer; generally NGINX (see prerequisites). How to set up the DNS record is beyond the scope of this document; you should check with your DNS provider.

Once set up, all requests will hit the load balancer, which in turn will route them to the Kubernetes pods that run your application(s).

NOTE: Note: If GitLab is installed using the GitLab Omnibus Helm Chart, there are two options: provide a static IP, or have one assigned. For more information see the relevant docs on the network prerequisites.

Quick start

If you are using GitLab.com, see our quick start guide for using Auto DevOps with GitLab.com and an external Kubernetes cluster on Google Cloud.

Enabling Auto DevOps

If you haven't done already, read the prerequisites to make full use of Auto DevOps. If this is your fist time, we recommend you follow the quick start guide.

To enable Auto DevOps to your project:

  1. Check that your project doesn't have a .gitlab-ci.yml, and remove it otherwise
  2. Go to your project's Settings > CI/CD > General pipelines settings and find the Auto DevOps section
  3. Select "Enable Auto DevOps"
  4. Optionally, but recommended, add in the base domain that will be used by Kubernetes to deploy your application
  5. Hit Save changes for the changes to take effect

Once saved, an Auto DevOps pipeline will be triggered on the default branch.

NOTE: Note: For GitLab versions 10.0 - 10.2, when enabling Auto DevOps, a pipeline needs to be manually triggered either by pushing a new commit to the repository or by visiting https://example.gitlab.com/<username>/<project>/pipelines/new and creating a new pipeline for your default branch, generally master.

NOTE: Note: If you are a GitLab Administrator, you can enable Auto DevOps instance wide in Admin Area > Settings > Continuous Integration and Deployment. Doing that, all the projects that haven't explicitly set an option will have Auto DevOps enabled by default.

Stages of Auto DevOps

The following sections describe the stages of Auto DevOps. Read them carefully to understand how each one works.

Auto Build

Auto Build creates a build of the application in one of two ways:

  • If there is a Dockerfile, it will use docker build to create a Docker image.
  • Otherwise, it will use Herokuish and Heroku buildpacks to automatically detect and build the application into a Docker image.

Either way, the resulting Docker image is automatically pushed to the Container Registry and tagged with the commit SHA.

CAUTION: Important: If you are also using Auto Review Apps and Auto Deploy and choose to provide your own Dockerfile, make sure you expose your application to port 5000 as this is the port assumed by the default Helm chart.

Auto Test

Auto Test automatically runs the appropriate tests for your application using Herokuish and Heroku buildpacks by analyzing your project to detect the language and framework. Several languages and frameworks are detected automatically, but if your language is not detected, you may succeed with a custom buildpack. Check the currently supported languages.

NOTE: Note: Auto Test uses tests you already have in your application. If there are no tests, it's up to you to add them.

Auto Code Quality

Auto Code Quality uses the open source codeclimate image to run static analysis and other code checks on the current code. The report is created, and is uploaded as an artifact which you can later download and check out.

In GitLab Starter, differences between the source and target branches are also shown in the merge request widget.

Auto SAST

Introduced in GitLab Ultimate 10.3.

Static Application Security Testing (SAST) uses the gl-sast Docker image to run static analysis on the current code and checks for potential security issues. Once the report is created, it's uploaded as an artifact which you can later download and check out.

In GitLab Ultimate, any security warnings are also shown in the merge request widget.

Auto SAST for Docker images

Introduced in GitLab 10.4.

Vulnerability Static Analysis for containers uses Clair to run static analysis on a Docker image and checks for potential security issues. Once the report is created, it's uploaded as an artifact which you can later download and check out.

In GitLab Ultimate, any security warnings are also shown in the merge request widget.

Auto Review Apps

NOTE: Note: This is an optional step, since many projects do not have a Kubernetes cluster available. If the prerequisites are not met, the job will silently be skipped.

CAUTION: Caution: Your apps should not be manipulated outside of Helm (using Kubernetes directly.) This can cause confusion with Helm not detecting the change, and subsequent deploys with Auto DevOps can undo your changes. Also, if you change something and want to undo it by deploying again, Helm may not detect that anything changed in the first place, and thus not realize that it needs to re-apply the old config.

Review Apps are temporary application environments based on the branch's code so developers, designers, QA, product managers, and other reviewers can actually see and interact with code changes as part of the review process. Auto Review Apps create a Review App for each branch.

The Review App will have a unique URL based on the project name, the branch name, and a unique number, combined with the Auto DevOps base domain. For example, user-project-branch-1234.example.com. A link to the Review App shows up in the merge request widget for easy discovery. When the branch is deleted, for example after the merge request is merged, the Review App will automatically be deleted.

Auto DAST

Introduced in GitLab Ultimate 10.4.

Dynamic Application Security Testing (DAST) uses the popular open source tool OWASP ZAProxy to perform an analysis on the current code and checks for potential security issues. Once the report is created, it's uploaded as an artifact which you can later download and check out.

In GitLab Ultimate, any security warnings are also shown in the merge request widget.

Auto Browser Performance Testing

Introduced in GitLab Premium 10.4.

Auto Browser Performance Testing utilizes the Sitespeed.io container to measure the performance of a web page. A JSON report is created and uploaded as an artifact, which includes the overall performance score for each page. By default, the root page of Review and Production environments will be tested. If you would like to add additional URL's to test, simply add the paths to a file named .gitlab-urls.txt in the root directory, one per line. For example:

/
/features
/direction

In GitLab Premium, performance differences between the source and target branches are shown in the merge request widget.

Auto Deploy

NOTE: Note: This is an optional step, since many projects do not have a Kubernetes cluster available. If the prerequisites are not met, the job will silently be skipped.

CAUTION: Caution: Your apps should not be manipulated outside of Helm (using Kubernetes directly.) This can cause confusion with Helm not detecting the change, and subsequent deploys with Auto DevOps can undo your changes. Also, if you change something and want to undo it by deploying again, Helm may not detect that anything changed in the first place, and thus not realize that it needs to re-apply the old config.

After a branch or merge request is merged into the project's default branch (usually master), Auto Deploy deploys the application to a production environment in the Kubernetes cluster, with a namespace based on the project name and unique project ID, for example project-4321.

Auto Deploy doesn't include deployments to staging or canary by default, but the Auto DevOps template contains job definitions for these tasks if you want to enable them.

You can make use of environment variables to automatically scale your pod replicas.

It's important to note that when a project is deployed to a Kubernetes cluster, it relies on a Docker image that has been pushed to the GitLab Container Registry. Kubernetes fetches this image and uses it to run the application. If the project is public, the image can be accessed by Kubernetes without any authentication, allowing us to have deployments more usable. If the project is private/internal, the Registry requires credentials to pull the image. Currently, this is addressed by providing CI_JOB_TOKEN as the password that can be used, but this token will no longer be valid as soon as the deployment job finishes. This means that Kubernetes can run the application, but in case it should be restarted or executed somewhere else, it cannot be accessed again.

Auto Monitoring

NOTE: Note: Check the prerequisites for Auto Monitoring to make this stage work.

Once your application is deployed, Auto Monitoring makes it possible to monitor your application's server and response metrics right out of the box. Auto Monitoring uses Prometheus to get system metrics such as CPU and memory usage directly from Kubernetes, and response metrics such as HTTP error rates, latency, and throughput from the NGINX server.

The metrics include:

  • Response Metrics: latency, throughput, error rate
  • System Metrics: CPU utilization, memory utilization

If GitLab has been deployed using the GitLab Omnibus Helm Chart, no configuration is required.

If you have installed GitLab using a different method, you need to:

  1. Deploy Prometheus into your Kubernetes cluster
  2. If you would like response metrics, ensure you are running at least version 0.9.0 of NGINX Ingress and enable Prometheus metrics.
  3. Finally, annotate the NGINX Ingress deployment to be scraped by Prometheus using prometheus.io/scrape: "true" and prometheus.io/port: "10254".

To view the metrics, open the Monitoring dashboard for a deployed environment.

Auto Metrics

Customizing

While Auto DevOps provides great defaults to get you started, you can customize almost everything to fit your needs; from custom buildpacks, to Dockerfiles, Helm charts, or even copying the complete CI/CD configuration into your project to enable staging and canary deployments, and more.

Custom buildpacks

If the automatic buildpack detection fails for your project, or if you want to use a custom buildpack, you can override the buildpack using a project variable or a .buildpack file in your project:

  • Project variable - Create a project variable BUILDPACK_URL with the URL of the buildpack to use.
  • .buildpack file - Add a file in your project's repo called .buildpack and add the URL of the buildpack to use on a line in the file. If you want to use multiple buildpacks, you can enter them in, one on each line.

CAUTION: Caution: Using multiple buildpacks isn't yet supported by Auto DevOps.

Custom Dockerfile

If your project has a Dockerfile in the root of the project repo, Auto DevOps will build a Docker image based on the Dockerfile rather than using buildpacks. This can be much faster and result in smaller images, especially if your Dockerfile is based on Alpine.

Custom Helm Chart

Auto DevOps uses Helm to deploy your application to Kubernetes. You can override the Helm chart used by bundling up a chart into your project repo or by specifying a project variable:

  • Bundled chart - If your project has a ./chart directory with a Chart.yaml file in it, Auto DevOps will detect the chart and use it instead of the default one. This can be a great way to control exactly how your application is deployed.
  • Project variable - Create a project variable AUTO_DEVOPS_CHART with the URL of a custom chart to use.

Customizing .gitlab-ci.yml

If you want to modify the CI/CD pipeline used by Auto DevOps, you can copy the Auto DevOps template into your project's repo and edit as you see fit.

Assuming that your project is new or it doesn't have a .gitlab-ci.yml file present:

  1. From your project home page, either click on the "Set up CI/CD" button, or click on the plus button and (+), then "New file"
  2. Pick .gitlab-ci.yml as the template type
  3. Select "Auto-DevOps" from the template dropdown
  4. Edit the template or add any jobs needed
  5. Give an appropriate commit message and hit "Commit changes"

TIP: Tip: The Auto DevOps template includes useful comments to help you customize it. For example, if you want deployments to go to a staging environment instead of directly to a production one, you can enable the staging job by renaming .staging to staging. Then make sure to uncomment the when key of the production job to turn it into a manual action instead of deploying automatically.

PostgreSQL database support

In order to support applications that require a database, PostgreSQL is provisioned by default. The credentials to access the database are preconfigured, but can be customized by setting the associated variables. These credentials can be used for defining a DATABASE_URL of the format:

postgres://user:password@postgres-host:postgres-port/postgres-database

Environment variables

The following variables can be used for setting up the Auto DevOps domain, providing a custom Helm chart, or scaling your application. PostgreSQL can be also be customized, and you can easily use a custom buildpack.

Variable Description
AUTO_DEVOPS_DOMAIN The Auto DevOps domain; by default set automatically by the Auto DevOps setting.
AUTO_DEVOPS_CHART The Helm Chart used to deploy your apps; defaults to the one provided by GitLab.
PRODUCTION_REPLICAS The number of replicas to deploy in the production environment; defaults to 1.
CANARY_PRODUCTION_REPLICAS The number of canary replicas to deploy for Canary Deployments in the production environment.
POSTGRES_ENABLED Whether PostgreSQL is enabled; defaults to "true". Set to false to disable the automatic deployment of PostgreSQL.
POSTGRES_USER The PostgreSQL user; defaults to user. Set it to use a custom username.
POSTGRES_PASSWORD The PostgreSQL password; defaults to testing-password. Set it to use a custom password.
POSTGRES_DB The PostgreSQL database name; defaults to the value of $CI_ENVIRONMENT_SLUG. Set it to use a custom database name.
BUILDPACK_URL The buildpack's full URL. It can point to either Git repositories or a tarball URL. For Git repositories, it is possible to point to a specific ref, for example https://github.com/heroku/heroku-buildpack-ruby.git#v142

TIP: Tip: Set up the replica variables using a project variable and scale your application by just redeploying it!

CAUTION: Caution: You should not scale your application using Kubernetes directly. This can cause confusion with Helm not detecting the change, and subsequent deploys with Auto DevOps can undo your changes.

Advanced replica variables setup

Apart from the two replica-related variables for production mentioned above, you can also use others for different environments.

There's a very specific mapping between Kubernetes' label named track, GitLab CI/CD environment names, and the replicas environment variable. The general rule is: TRACK_ENV_REPLICAS. Where:

  • TRACK: The capitalized value of the track Kubernetes label in the Helm Chart app definition. If not set, it will not be taken into account to the variable name.
  • ENV: The capitalized environment name of the deploy job that is set in .gitlab-ci.yml.

That way, you can define your own TRACK_ENV_REPLICAS variables with which you will be able to scale the pod's replicas easily.

In the example below, the environment's name is qa which would result in looking for the QA_REPLICAS environment variable:

QA testing:
  stage: deploy
  environment:
    name: qa
  script:
  - deploy qa

If, in addition, there was also a track: foo defined in the application's Helm chart, like:

replicaCount: 1
image:
  repository: gitlab.example.com/group/project
  tag: stable
  pullPolicy: Always
  secrets:
    - name: gitlab-registry
application:
  track: foo
  tier: web
service:
  enabled: true
  name: web
  type: ClusterIP
  url: http://my.host.com/
  externalPort: 5000
  internalPort: 5000

then the environment variable would be FOO_QA_REPLICAS.

Currently supported languages

NOTE: Note: Not all buildpacks support Auto Test yet, as it's a relatively new enhancement. All of Heroku's officially supported languages support it, and some third-party buildpacks as well e.g., Go, Node, Java, PHP, Python, Ruby, Gradle, Scala, and Elixir all support Auto Test, but notably the multi-buildpack does not.

As of GitLab 10.0, the supported buildpacks are:

- heroku-buildpack-multi     v1.0.0
- heroku-buildpack-ruby      v168
- heroku-buildpack-nodejs    v99
- heroku-buildpack-clojure   v77
- heroku-buildpack-python    v99
- heroku-buildpack-java      v53
- heroku-buildpack-gradle    v23
- heroku-buildpack-scala     v78
- heroku-buildpack-play      v26
- heroku-buildpack-php       v122
- heroku-buildpack-go        v72
- heroku-buildpack-erlang    fa17af9
- buildpack-nginx            v8

Limitations

The following restrictions apply.

Private project support

CAUTION: Caution: Private project support in Auto DevOps is experimental.

When a project has been marked as private, GitLab's Container Registry requires authentication when downloading containers. Auto DevOps will automatically provide the required authentication information to Kubernetes, allowing temporary access to the registry. Authentication credentials will be valid while the pipeline is running, allowing for a successful initial deployment.

After the pipeline completes, Kubernetes will no longer be able to access the Container Registry. Restarting a pod, scaling a service, or other actions which require on-going access to the registry may fail. On-going secure access is planned for a subsequent release.

Troubleshooting

  • Auto Build and Auto Test may fail in detecting your language/framework. There may be no buildpack for your application, or your application may be missing the key files the buildpack is looking for. For example, for ruby apps, you must have a Gemfile to be properly detected, even though it is possible to write a Ruby app without a Gemfile. Try specifying a custom buildpack.
  • Auto Test may fail because of a mismatch between testing frameworks. In this case, you may need to customize your .gitlab-ci.yml with your test commands.

Disable the banner instance wide

If an administrator would like to disable the banners on an instance level, this feature can be disabled either through the console:

sudo gitlab-rails console

Then run:

Feature.get(:auto_devops_banner_disabled).enable

Or through the HTTP API with an admin access token:

curl --data "value=true" --header "PRIVATE-TOKEN: personal_access_token" https://gitlab.example.com/api/v4/features/auto_devops_banner_disabled