docker-compose.yml#

The docker-compose.yml file is used by Lagoon to:

Learn which services/containers should be deployed.
Define how the images for the containers are built.
Define additional configurations like persistent volumes.

Docker Compose (the tool) is very strict in validating the content of the YAML file, so we can only do configuration within labels of a service definition.

Warning

Lagoon only reads the labels, service names, image names and build definitions from a docker-compose.yml file. Definitions like: ports, environment variables, volumes, networks, links, users, etc. are IGNORED.

This is intentional, as the docker-compose file is there to define your local environment configuration. Lagoon learns from the lagoon.type the type of service you are deploying and from that knows about ports, networks and any additional configuration that this service might need.

Here a straightforward example of a docker-compose.yml file for Drupal:

docker-compose.yml

version: '2.3'

x-lagoon-project:
  # Lagoon project name (leave `&lagoon-project` when you edit this)
  &lagoon-project drupal-example

x-volumes:
  &default-volumes
    # Define all volumes you would like to have real-time mounted into the docker containers
    volumes:
      - .:/app:delegated

x-environment:
  &default-environment
    LAGOON_PROJECT: *lagoon-project
    # Route that should be used locally, if you are using pygmy, this route *must* end with .docker.amazee.io
    LAGOON_ROUTE: http://drupal-example.docker.amazee.io
    # Uncomment if you want to have the system behave as it will in production
    #LAGOON_ENVIRONMENT_TYPE: production
    # Uncomment to enable Xdebug and then restart via `docker-compose up -d`
    #XDEBUG_ENABLE: "true"

x-user:
  &default-user
    # The default user under which the containers should run. Change this if you are on linux and run with another user than ID `1000`
    user: '1000'

services:

  nginx:
    build:
      context: .
      dockerfile: nginx.dockerfile
    labels:
      lagoon.type: nginx-php-persistent # (1)
      lagoon.persistent: /app/web/sites/default/files/

  php:
    build:
      context: .
      dockerfile: php.dockerfile
    labels:
      lagoon.type: nginx-php-persistent # (2)
      lagoon.name: nginx
      lagoon.persistent: /app/web/sites/default/files/

  mariadb:
    image: amazeeio/mariadb-drupal
    labels:
      lagoon.type: mariadb

Note the multi-container pods here.
Note the multi-container pods here.

Basic settings#

x-lagoon-project:

This is the machine name of your project, define it here. We’ll use “drupal-example.”

x-volumes:

This tells Lagoon what to mount into the container. Your web application lives in /app, but you can add or change this if needed.

x-environment:

Here you can set your local development URL. If you are using pygmy, it must end with .docker.amazee.io.
If you want to exactly mimic the production environment, uncomment LAGOON_ENVIRONMENT_TYPE: production.
If you want to enable Xdebug, uncomment DEBUG_ENABLE: "true".

x-user:

You are unlikely to need to change this, unless you are on Linux and would like to run with a user other than 1000.

`services`#

This defines all the services you want to deploy. Unfortunately, Docker Compose calls them services, even though they are actually containers. Going forward we'll be calling them services, and throughout this documentation.

The name of the service (nginx, php, and mariadb in the example above) is used by Lagoon as the name of the Kubernetes pod (yet another term - again, we'll be calling them services) that is generated, plus also any additional Kubernetes objects that are created based on the defined lagoon.type, which could be things like services, routes, persistent storage, etc.

Please note that service names adhere to the RFC 1035 DNS label standard. Service names must:

contain at most 63 characters
contain only lowercase alphanumeric characters or '-'
start with an alphabetic character
end with an alphanumeric character

Warning

Once you have set the name of a service, do NOT rename it. This will cause all kind of havoc in your containers and break things.

Docker Images#

`build`#

If you want Lagoon to build a Dockerfile for your service during every deployment, you can define it here:

build

context
- The build context path that should be passed on into the docker build command.
dockerfile:
- Location and name of the Dockerfile that should be built.

Warning

Lagoon does NOT support the short version of build: <Dockerfile> and will fail if it finds such a definition.

`image`#

If you don't need to build a Dockerfile and just want to use an existing Dockerfile, define it via image.

Types#

Lagoon needs to know what type of service you are deploying in order to configure the correct Kubernetes or OpenShift objects.

This is done via the lagoon.type label. There are many different types to choose from. Check Service Types to see all of them and their additional configuration possibilities.

Skip/Ignore containers#

If you'd like Lagoon to ignore a service completely - for example, you need a container only during local development - give it the type none.

Persistent Storage#

Some containers need persistent storage. Lagoon allows for each container to have a maximum of one persistent storage volume attached to the container. You can configure the container to request its own persistent storage volume (which can then be mounted by other container), or you can tell the container to mount the persistent storage created by another container.

In many cases, Lagoon knows where that persistent storage needs to go. For example, for a MariaDB container, Lagoon knows that the persistent storage should be put into /var/lib/mysql , and puts it there automatically without any extra configuration to define that. For some situations, though, Lagoon needs your help to know where to put the persistent storage:

lagoon.persistent - The absolute path where the persistent storage should be mounted (the above example uses /app/web/sites/default/files/ which is where Drupal expects its persistent storage).
lagoon.persistent.name - Tells Lagoon to not create a new persistent storage for that service, but instead mounts the persistent storage of another defined service into this service.
lagoon.persistent.size - The size of persistent storage you require (Lagoon usually gives you minimum 5G of persistent storage, if you need more, define it here).
lagoon.persistent.class - By default Lagoon automatically assigns the right storage class for your service (like SSDs for MySQL, bulk storage for Nginx, etc.). If you need to overwrite this, you can do so here. This is highly dependent on the underlying Kubernetes/OpenShift that Lagoon runs on. Ask your Lagoon administrator about this.

Auto-generated Routes#

The docker-compose.yml file also supports per-service enabling and disabling of autogenerated routes

lagoon.autogeneratedroute: false label will stop a route from being automatically created for that service. It can be applied to all services with autogenerated routes, but is mostly useful for the basic and basic-persistent service types when used to create an additional internal-facing service for a database service or similar. The inverse is also true - it will enable an auto-generated route for a service when the .lagoon.yml file disables them.

Multi-Container Pods#

Kubernetes and OpenShift don't deploy plain containers. Instead, they deploy pods, with each one or more containers. Usually Lagoon creates a single pod with a container inside for each defined docker-compose service. For some cases, we need to put two containers inside a single pod, as these containers are so dependent on each other that they should always stay together. An example for such a situation is the PHP and NGINX containers that both contain PHP code of a web application like Drupal.

For these cases, it is possible to tell Lagoon which services should stay together, which is done in the following way (remember that we are calling containers services because of docker-compose:

Define both services with a lagoon.type that expects two services (in the example this is nginx-php-persistent defined on the nginx and php services).
Link the second service with the first one, defining the label lagoon.name of the second one with the first one. (in the example this is done with defining lagoon.name: nginx).

This will cause Lagoon to realize that the nginx and php containers are combined in a pod that will be called nginx.

Warning

Once you have set the lagooon.name of a service, do NOT rename it. This will cause all kind of havoc in your containers and break things.

Lagoon still needs to understand which of the two services is the actual individual service type (nginx and php in this case). It does this by searching for service names with the same name that are given by the type, so nginx-php-persistent expects one service with the name nginx and one with php in the docker-compose.yml. If for any reason you want to use different names for the services, or you need for than one pod with the type nginx-php-persistent there is an additional label lagoon.deployment.servicetype which can be used to define the actual service type.

An example:

docker-compose.yml

nginx:
    build:
      context: .
      dockerfile: nginx.dockerfile
    labels:
      lagoon.type: nginx-php-persistent
      lagoon.persistent: /app/web/sites/default/files/
      lagoon.name: nginx # If this isn't present, Lagoon will use the container name, which in this case is nginx.
      lagoon.deployment.servicetype: nginx
php:
    build:
      context: .
      dockerfile: php.dockerfile
    labels:
      lagoon.type: nginx-php-persistent
      lagoon.persistent: /app/web/sites/default/files/
      lagoon.name: nginx # We want this service to be part of the NGINX pod in Lagoon.
      lagoon.deployment.servicetype: php

In the example above, the services are named nginx and php (but you can call them whatever you want). The lagoon.name tells Lagoon which services go together - all of the services with the same name go together.

In order for Lagoon to realize which one is the nginx and which one is the php service, we define it via lagoon.deployment.servicetype: nginx and lagoon.deployment.servicetype: php.

Helm Templates (Kubernetes only)#

Lagoon uses Helm for templating on Kubernetes. To do this, a series of Charts are included with the build-deploy-tool image.

Custom Rollout Monitor Types#

By default, Lagoon expects that services from custom templates are rolled out via a DeploymentConfig object within Kubernetes or Openshift. It monitors the rollout based on this object. In some cases, the services that are defined via custom deployment need a different way of monitoring. This can be defined via lagoon.rollout:

deploymentconfig - This is the default. Expects a DeploymentConfig object in the template for the service.
statefulset - Expects a Statefulset object in the template for the service.
daemonset - Expects a Daemonset object in the template for the service.
false - Will not monitor any rollouts, and will just be happy if the template applies and does not throw any errors.

You can also overwrite the rollout for just one specific environment. This is done in .lagoon.yml.

Docker Compose v2 compatibility#

Bug

Note that while using older versions of Docker Compose V2 locally, you may experience some known issues - these have been resolved in later releases (v2.17.3 onwards).

The resolution for these errors is usually to update (or install a later version of) the version of Docker Compose you are using, either standalone or by upgrading the version of Docker Desktop you're using. See the Docker Desktop release notes for more information

Docker Compose output indicating depends_on error

Failed to solve with frontend dockerfile.v0: failed to create LLB definition: pull access denied, repository does not exist or may require authorization

or

Failed to solve: drupal9-base-cli: pull access denied, repository does not exist or may require authorization: server message: insufficient_scope: authorization failed`

These are resolved in Docker Compose v2.13.0.
This message means that your build has tried to access a Docker image that hasn't been built yet. As BuildKit builds in parallel, if you have a Docker image that inherits another one (as we do in Drupal with the CLI).
You can also use the target field inside the build to reconfigure as a multi-stage build.
If you are already running a newer Docker Compose version, this error may be because you're defaulting to using a docker-container build context with buildx. You should make sure that docker buildx ls shows the docker builder as default, not a docker-container based one. Check the docs on Docker buildx here.

Docker Compose output indicating volumes_from error

no such service: container:amazeeio-ssh-agent

This is resolved in Docker Compose v2.17.3.
This message means that the service that provides SSH access into locally running containers runs outside of your Docker Compose stack and is inaccessible.
The section can also be removed from your docker-compose.yml file if you don't require SSH access from inside your local environment.

BuildKit and Lagoon#

BuildKit is a toolkit for converting source code to build artifacts in an efficient, expressive and repeatable manner.

With the release of Lagoon v2.11.0, Lagoon now provides support for more advanced BuildKit-based docker-compose builds. To enable BuildKit for your Project or Environment, add DOCKER_BUILDKIT=1 as a build-time variable to your Lagoon project or environment.

Docker Compose Errors in Lagoon Builds#

See the Lagoon Build Errors page for how to resolve common build errors with Docker Compose.

Common Docker Compose Issues#

This section outlines some of the more common Docker Compose errors, and how to remedy them. These may present in local development, or as Lagoon Build Errors and Warnings.

Dual Mapping keys#

Docker Compose output indicating mapping key error

ERR: yaml: unmarshal errors: line 22: mapping key "<<" already defined at line 21

Early releases of the Lagoon examples contained a pair of YAML aliases attached to services to provide volumes and user code. Newer releases of Docker Compose will report this as an error. While all examples have now been updated, there may be some older codebases around that need updating.

This error arises from Docker Compose not knowing what it is inserting into the array, so just assuming it may be duplicate.

If your docker-compose.yml contains one or more of this (or similar) code blocks, you will be affected.

Docker Compose error with dual mapping keys

...
    << : [*default-volumes]
    << : [*default-user]
...

The corrected version combines both aliases into a single mapping key - you'll need to remedy all occurrances.

Docker Compose correct insertion of multiple alias mapping keys

...
    << : [*default-volumes, *default-user]
...

docker-compose.yml#

Basic settings#

services#

Docker Images#

build#

image#

Types#

Skip/Ignore containers#

Persistent Storage#

Auto-generated Routes#

Multi-Container Pods#

Helm Templates (Kubernetes only)#

Custom Rollout Monitor Types#

Docker Compose v2 compatibility#

BuildKit and Lagoon#

Docker Compose Errors in Lagoon Builds#

Common Docker Compose Issues#

Dual Mapping keys#

`services`#

`build`#

`image`#