debian-mirror-gitlab/doc/ci/environments.md

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reference

Environments and deployments

Introduced in GitLab 8.9.

Environments allow control of the continuous deployment of your software, all within GitLab.

Introduction

There are many stages required in the software development process before the software is ready for public consumption.

For example:

1. Develop your code.
2. Test your code.
3. Deploy your code into a testing or staging environment before you release it to the public.

This helps find bugs in your software, and also in the deployment process as well.

GitLab CI/CD is capable of not only testing or building your projects, but also deploying them in your infrastructure, with the added benefit of giving you a way to track your deployments. In other words, you will always know what is currently being deployed or has been deployed on your servers.

It's important to know that:

• Environments are like tags for your CI jobs, describing where code gets deployed.
• Deployments are created when jobs deploy versions of code to environments, so every environment can have one or more deployments.

GitLab:

• Provides a full history of your deployments for each environment.
• Keeps track of your deployments, so you always know what is currently being deployed on your servers.

If you have a deployment service such as Kubernetes associated with your project, you can use it to assist with your deployments, and can even access a web terminal for your environment from within GitLab!

Configuring environments

Configuring environments involves:

1. Understanding how pipelines work.
2. Defining environments in your project's .gitlab-ci.yml file.

The rest of this section illustrates how to configure environments and deployments using an example scenario. It assumes you have already:

• Created a project in GitLab.
• Set up a Runner.

In the scenario:

• We are developing an application.
• We want to run tests and build our app on all branches.
• Our default branch is master.
• We deploy the app only when a pipeline on master branch is run.

Defining environments

Let's consider the following .gitlab-ci.yml example:

stages:
  - test
  - build
  - deploy

test:
  stage: test
  script: echo "Running tests"

build:
  stage: build
  script: echo "Building the app"

deploy_staging:
  stage: deploy
  script:
    - echo "Deploy to staging server"
  environment:
    name: staging
    url: https://staging.example.com
  only:
  - master

We have defined three stages:

• test
• build
• deploy

The jobs assigned to these stages will run in this order. If any job fails, then the pipeline fails and jobs that are assigned to the next stage won't run.

In our case:

• The test job will run first.
• Then the build job.
• Lastly the deploy_staging job.

With this configuration, we:

• Check that the tests pass.
• Ensure that our app is able to be built successfully.
• Lastly we deploy to the staging server.

NOTE: Note: The environment keyword is just a hint for GitLab that this job actually deploys to the name environment. It can also have a url that is exposed in various places within GitLab. Each time a job that has an environment specified succeeds, a deployment is recorded, storing the Git SHA and environment name.

In summary, with the above .gitlab-ci.yml we have achieved the following:

• All branches will run the test and build jobs.
• The deploy_staging job will run only on the master branch, which means all merge requests that are created from branches don't get deployed to the staging server.
• When a merge request is merged, all jobs will run and the deploy_staging job will deploy our code to a staging server while the deployment will be recorded in an environment named staging.

Starting with GitLab 8.15, the environment name is exposed to the Runner in two forms: $CI_ENVIRONMENT_NAME, and $CI_ENVIRONMENT_SLUG. The first is the name given in .gitlab-ci.yml (with any variables expanded), while the second is a "cleaned-up" version of the name, suitable for use in URLs, DNS, etc.

Starting with GitLab 9.3, the environment URL is exposed to the Runner via $CI_ENVIRONMENT_URL. The URL is expanded from .gitlab-ci.yml, or if the URL was not defined there, the external URL from the environment is used.

Configuring manual deployments

Adding when: manual to an automatically executed job's configuration converts it to a job requiring manual action.

To expand on the previous example, the following includes another job that deploys our app to a production server and is tracked by a production environment.

The .gitlab-ci.yml file for this is as follows:

stages:
  - test
  - build
  - deploy

test:
  stage: test
  script: echo "Running tests"

build:
  stage: build
  script: echo "Building the app"

deploy_staging:
  stage: deploy
  script:
    - echo "Deploy to staging server"
  environment:
    name: staging
    url: https://staging.example.com
  only:
  - master

deploy_prod:
  stage: deploy
  script:
    - echo "Deploy to production server"
  environment:
    name: production
    url: https://example.com
  when: manual
  only:
  - master

The when: manual action:

• Exposes a "play" button in GitLab's UI for that job.
• Means the deploy_prod job will only be triggered when the "play" button is clicked.

You can find the "play" button in the pipelines, environments, deployments, and jobs views.

View	Screenshot
Pipelines
Single pipeline
Environments
Deployments
Jobs

Clicking on the play button in any view will trigger the deploy_prod job, and the deployment will be recorded as a new environment named production.

NOTE: Note: If your environment's name is production (all lowercase), it will get recorded in Cycle Analytics.

Configuring dynamic environments

Regular environments are good when deploying to "stable" environments like staging or production.

However, for environments for branches other than master, dynamic environments can be used. Dynamic environments make it possible to create environments on the fly by declaring their names dynamically in .gitlab-ci.yml.

Dynamic environments are a fundamental part of Review apps.

Allowed variables

The name and url parameters for dynamic environments can use most available CI/CD variables, including:

• Predefined environment variables
• Project and group variables
• .gitlab-ci.yml variables

However, you cannot use variables defined:

• Under script.
• On the Runner's side.

There are also other variables that are unsupported in the context of environment:name. For more information, see Where variables can be used.

Example configuration

GitLab Runner exposes various environment variables when a job runs, so you can use them as environment names.

In the following example, the job will deploy to all branches except master:

deploy_review:
  stage: deploy
  script:
    - echo "Deploy a review app"
  environment:
    name: review/$CI_COMMIT_REF_NAME
    url: https://$CI_ENVIRONMENT_SLUG.example.com
  only:
    - branches
  except:
    - master

In this example:

• The job's name is deploy_review and it runs on the deploy stage.
• We set the environment with the environment:name as review/$CI_COMMIT_REF_NAME. Since the environment name can contain slashes (/), we can use this pattern to distinguish between dynamic and regular environments.
• We tell the job to run only on branches, except master.

For the value of:

• environment:name, the first part is review, followed by a / and then $CI_COMMIT_REF_NAME, which receives the value of the branch name.

• environment:url, we want a specific and distinct URL for each branch. $CI_COMMIT_REF_NAME may contain a / or other characters that would be invalid in a domain name or URL, so we use $CI_ENVIRONMENT_SLUG to guarantee that we get a valid URL.

  For example, given a $CI_COMMIT_REF_NAME of 100-Do-The-Thing, the URL will be something like https://100-do-the-4f99a2.example.com. Again, the way you set up the web server to serve these requests is based on your setup.

  We have used $CI_ENVIRONMENT_SLUG here because it is guaranteed to be unique. If you're using a workflow like GitLab Flow, collisions are unlikely and you may prefer environment names to be more closely based on the branch name. In that case, you could use $CI_COMMIT_REF_SLUG in environment:url in the example above: https://$CI_COMMIT_REF_SLUG.example.com, which would give a URL of https://100-do-the-thing.example.com.

NOTE: Note: You are not required to use the same prefix or only slashes (/) in the dynamic environments' names. However, using this format will enable the grouping similar environments feature.

Complete example

The configuration in this section provides a full development workflow where your app is:

• Tested.
• Built.
• Deployed as a Review App.
• Deployed to a staging server once the merge request is merged.
• Finally, able to be manually deployed to the production server.

The following combines the previous configuration examples, including:

• Defining simple environments for testing, building, and deployment to staging.
• Adding manual actions for deployment to production.
• Creating dynamic environments for deployments for reviewing.

stages:
  - test
  - build
  - deploy

test:
  stage: test
  script: echo "Running tests"

build:
  stage: build
  script: echo "Building the app"

deploy_review:
  stage: deploy
  script:
    - echo "Deploy a review app"
  environment:
    name: review/$CI_COMMIT_REF_NAME
    url: https://$CI_ENVIRONMENT_SLUG.example.com
  only:
    - branches
  except:
    - master

deploy_staging:
  stage: deploy
  script:
    - echo "Deploy to staging server"
  environment:
    name: staging
    url: https://staging.example.com
  only:
  - master

deploy_prod:
  stage: deploy
  script:
    - echo "Deploy to production server"
  environment:
    name: production
    url: https://example.com
  when: manual
  only:
  - master

A more realistic example would also include copying files to a location where a webserver (for example, NGINX) could then access and serve them.

The example below will copy the public directory to /srv/nginx/$CI_COMMIT_REF_SLUG/public:

review_app:
  stage: deploy
  script:
    - rsync -av --delete public /srv/nginx/$CI_COMMIT_REF_SLUG
  environment:
    name: review/$CI_COMMIT_REF_NAME
    url: https://$CI_COMMIT_REF_SLUG.example.com

This example requires that NGINX and GitLab Runner are set up on the server this job will run on.

NOTE: Note: See the limitations section for some edge cases regarding the naming of your branches and Review Apps.

The complete example provides the following workflow to developers:

• Create a branch locally.
• Make changes and commit them.
• Push the branch to GitLab.
• Create a merge request.

Behind the scenes, GitLab Runner will:

• Pick up the changes and start running the jobs.
• Run the jobs sequentially as defined in stages:
  • First, run the tests.
  • If the tests succeed, build the app.
  • If the build succeeds, the app is deployed to an environment with a name specific to the branch.

So now, every branch:

• Gets its own environment.
• Is deployed to its own unique location, with the added benefit of:
  • Having a history of deployments.
  • Being able to rollback changes if needed.

For more information, see Using the environment URL.

Protected environments

Environments can be "protected", restricting access to them.

For more information, see Protected environments.

Working with environments

Once environments are configured, GitLab provides many features for working with them, as documented below.

Viewing environments and deployments

A list of environments and deployment statuses is available on each project's Operations > Environments page.

For example:

This example shows:

• The environment's name with a link to its deployments.
• The last deployment ID number and who performed it.
• The job ID of the last deployment with its respective job name.
• The commit information of the last deployment, such as who committed it, to what branch, and the Git SHA of the commit.
• The exact time the last deployment was performed.
• A button that takes you to the URL that you defined under the environment keyword in .gitlab-ci.yml.
• A button that re-deploys the latest deployment, meaning it runs the job defined by the environment name for that specific commit.

The information shown in the Environments page is limited to the latest deployments, but an environment can have multiple deployments.

Notes:

• While you can create environments manually in the web interface, we recommend that you define your environments in .gitlab-ci.yml first. They will be automatically created for you after the first deploy.
• The environments page can only be viewed by users with Reporter permission and above. For more information on permissions, see the permissions documentation.
• Only deploys that happen after your .gitlab-ci.yml is properly configured will show up in the Environment and Last deployment lists.

Viewing deployment history

GitLab keeps track of your deployments, so you:

• Always know what is currently being deployed on your servers.
• Can have the full history of your deployments for every environment.

Clicking on an environment shows the history of its deployments. Here's an example Environments page with multiple deployments:

This view is similar to the Environments page, but all deployments are shown. Also in this view is a Rollback button. For more information, see Retrying and rolling back.

Retrying and rolling back

If there is a problem with a deployment, you can retry it or roll it back.

To retry or rollback a deployment:

1. Navigate to Operations > Environments.
2. Click on the environment.
3. In the deployment history list for the environment, click the:
   • Retry button next to the last deployment, to retry that deployment.
   • Rollback button next to a previously successful deployment, to roll back to that deployment.

NOTE: Note: The defined deployment process in the job's script determines whether the rollback succeeds or not.

Using the environment URL

The environment URL is exposed in a few places within GitLab:

• In a merge request widget as a link:
• In the Environments view as a button:
• In the Deployments view as a button:

You can see this information in a merge request itself if:

• The merge request is eventually merged to the default branch (usually master).
• That branch also deploys to an environment (for example, staging or production).

For example:

Going from source files to public pages

With GitLab's Route Maps you can go directly from source files to public pages in the environment set for Review Apps.

Stopping an environment

Stopping an environment:

• Moves it from the list of Available environments to the list of Stopped environments on the Environments page.
• Executes an on_stop action, if defined.

This is often used when multiple developers are working on a project at the same time, each of them pushing to their own branches, causing many dynamic environments to be created.

NOTE: Note: Starting with GitLab 8.14, dynamic environments are stopped automatically when their associated branch is deleted.

Automatically stopping an environment

Environments can be stopped automatically using special configuration.

Consider the following example where the deploy_review job calls stop_review to clean up and stop the environment:

deploy_review:
  stage: deploy
  script:
    - echo "Deploy a review app"
  environment:
    name: review/$CI_COMMIT_REF_NAME
    url: https://$CI_ENVIRONMENT_SLUG.example.com
    on_stop: stop_review
  only:
    - branches
  except:
    - master

stop_review:
  stage: deploy
  variables:
    GIT_STRATEGY: none
  script:
    - echo "Remove review app"
  when: manual
  environment:
    name: review/$CI_COMMIT_REF_NAME
    action: stop

Setting the GIT_STRATEGY to none is necessary in the stop_review job so that the GitLab Runner won't try to check out the code after the branch is deleted.

When you have an environment that has a stop action defined (typically when the environment describes a Review App), GitLab will automatically trigger a stop action when the associated branch is deleted. The stop_review job must be in the same stage as the deploy_review job in order for the environment to automatically stop.

You can read more in the .gitlab-ci.yml reference.

Grouping similar environments

Introduced in GitLab 8.14.

As documented in Configuring dynamic environments, you can prepend environment name with a word, followed by a /, and finally the branch name, which is automatically defined by the CI_COMMIT_REF_NAME variable.

In short, environments that are named like type/foo are all presented under the same group, named type.

In our minimal example, we named the environments review/$CI_COMMIT_REF_NAME where $CI_COMMIT_REF_NAME is the branch name. Here is a snippet of the example:

deploy_review:
  stage: deploy
  script:
    - echo "Deploy a review app"
  environment:
    name: review/$CI_COMMIT_REF_NAME

In this case, if you visit the Environments page and the branches exist, you should see something like:

Monitoring environments

Notes:

• For the monitoring dashboard to appear, you need to:
  • Enable the Prometheus integration.
  • Configure Prometheus to collect at least one supported metric.
• With GitLab 9.2, all deployments to an environment are shown directly on the monitoring dashboard.

If you have enabled Prometheus for monitoring system and response metrics, you can monitor the behavior of your app running in each environment.

Once configured, GitLab will attempt to retrieve supported performance metrics for any environment that has had a successful deployment. If monitoring data was successfully retrieved, a Monitoring button will appear for each environment.

Clicking on the Monitoring button will display a new page showing up to the last 8 hours of performance data. It may take a minute or two for data to appear after initial deployment.

All deployments to an environment are shown directly on the monitoring dashboard, which allows easy correlation between any changes in performance and new versions of the app, all without leaving GitLab.

Linking to external dashboard

Add a button to the Monitoring dashboard linking directly to your existing external dashboards.

Web terminals

Web terminals were added in GitLab 8.15 and are only available to project Maintainers and Owners.

If you deploy to your environments with the help of a deployment service (for example, the Kubernetes integration), GitLab can open a terminal session to your environment.

This is a powerful feature that allows you to debug issues without leaving the comfort of your web browser. To enable it, just follow the instructions given in the service integration documentation.

Once enabled, your environments will gain a "terminal" button:

You can also access the terminal button from the page for a specific environment:

Wherever you find it, clicking the button will take you to a separate page to establish the terminal session:

This works just like any other terminal. You'll be in the container created by your deployment so you can:

• Run shell commands and get responses in real time.
• Check the logs.
• Try out configuration or code tweaks etc.

You can open multiple terminals to the same environment, they each get their own shell session and even a multiplexer like screen or tmux.

NOTE: Note: Container-based deployments often lack basic tools (like an editor), and may be stopped or restarted at any time. If this happens, you will lose all your changes. Treat this as a debugging tool, not a comprehensive online IDE.

Check out deployments locally

Since GitLab 8.13, a reference in the Git repository is saved for each deployment, so knowing the state of your current environments is only a git fetch away.

In your Git configuration, append the [remote "<your-remote>"] block with an extra fetch line:

fetch = +refs/environments/*:refs/remotes/origin/environments/*

Scoping environments with specs (PREMIUM)

Introduced in GitLab Premium 9.4.

You can limit the environment scope of a variable by defining which environments it can be available for.

Wildcards can be used, and the default environment scope is *, which means any jobs will have this variable, not matter if an environment is defined or not.

For example, if the environment scope is production, then only the jobs having the environment production defined would have this specific variable. Wildcards (*) can be used along with the environment name, therefore if the environment scope is review/* then any jobs with environment names starting with review/ would have that particular variable.

Some GitLab features can behave differently for each environment. For example, you can create a secret variable to be injected only into a production environment. (PREMIUM)

In most cases, these features use the environment specs mechanism, which offers an efficient way to implement scoping within each environment group.

Let's say there are four environments:

• production
• staging
• review/feature-1
• review/feature-2

Each environment can be matched with the following environment spec:

Environment Spec	production	staging	review/feature-1	review/feature-2
*	Matched	Matched	Matched	Matched
production	Matched
staging		Matched
review/*			Matched	Matched
review/feature-1			Matched

As you can see, you can use specific matching for selecting a particular environment, and also use wildcard matching (*) for selecting a particular environment group, such as Review Apps (review/*).

NOTE: Note: The most specific spec takes precedence over the other wildcard matching. In this case, review/feature-1 spec takes precedence over review/* and * specs.

Limitations

In the environment: name, you are limited to only the predefined environment variables. Re-using variables defined inside script as part of the environment name will not work.

Further reading

Below are some links you may find interesting:

• The .gitlab-ci.yml definition of environments
• A blog post on Deployments & Environments
• Review Apps - Use dynamic environments to deploy your code for every branch
• Deploy Boards for your applications running on Kubernetes (PREMIUM)