Use provider services
Docker Compose supports provider services, which allow integration with services whose lifecycles are managed by third-party components rather than by Compose itself.
This feature enables you to define and utilize platform-specific services without the need for manual setup or direct lifecycle management.
What are provider services?
Provider services are a special type of service in Compose that represents platform capabilities rather than containers. They allow you to declare dependencies on specific platform features that your application needs.
When you define a provider service in your Compose file, Compose works with the platform to provision and configure the requested capability, making it available to your application services.
Using provider services
To use a provider service in your Compose file, you need to:
- Define a service with the
provider
attribute - Specify the
type
of provider you want to use - Configure any provider-specific options
- Declare dependencies from your application services to the provider service
Here's a basic example:
services:
database:
provider:
type: awesomecloud
options:
type: mysql
foo: bar
app:
image: myapp
depends_on:
- database
Notice the dedicated provider
attribute in the database
service.
This attribute specifies that the service is managed by a provider and lets you define options specific to that provider type.
The depends_on
attribute in the app
service specifies that it depends on the database
service.
This means that the database
service will be started before the app
service, allowing the provider information
to be injected into the app
service.
How it works
During the docker compose up
command execution, Compose identifies services relying on providers and works with them to provision
the requested capabilities. The provider then populates Compose model with information about how to access the provisioned resource.
This information is passed to services that declare a dependency on the provider service, typically through environment variables. The naming convention for these variables is:
<<PROVIDER_SERVICE_NAME>>_<<VARIABLE_NAME>>
For example, if your provider service is named database
, your application service might receive environment variables like:
DATABASE_URL
with the URL to access the provisioned resourceDATABASE_TOKEN
with an authentication token- Other provider-specific variables
Your application can then use these environment variables to interact with the provisioned resource.
Provider types
The type
field in a provider service references the name of either:
- A Docker CLI plugin (e.g.,
docker-model
) - A binary available in the user's PATH
When Compose encounters a provider service, it looks for a plugin or binary with the specified name to handle the provisioning of the requested capability.
For example, if you specify type: model
, Compose will look for a Docker CLI plugin named docker-model
or a binary named model
in the PATH.
services:
ai-runner:
provider:
type: model # Looks for docker-model plugin or model binary
options:
model: ai/example-model
The plugin or binary is responsible for:
- Interpreting the options provided in the provider service
- Provisioning the requested capability
- Returning information about how to access the provisioned resource
This information is then passed to dependent services as environment variables.
Benefits of using provider services
Using provider services in your Compose applications offers several benefits:
- Simplified configuration: You don't need to manually configure and manage platform capabilities
- Declarative approach: You can declare all your application's dependencies in one place
- Consistent workflow: You use the same Compose commands to manage your entire application, including platform capabilities
Creating your own provider
If you want to create your own provider to extend Compose with custom capabilities, you can implement a Compose plugin that registers provider types.
For detailed information on how to create and implement your own provider, refer to the
Compose Extensions documentation.
This guide explains the extension mechanism that allows you to add new provider types to Compose.