/score-compose

Reference implementation for docker-compose target platform support

Primary LanguageGoApache License 2.0Apache-2.0

ci release

score-compose

score-compose is a reference implementation of the Score specification for Docker compose, primarily used for local development. It supports most aspects of the Score specification and provides a powerful resource provisioning system for supplying and customising the dynamic configuration of attached services such as databases, queues, storage, and other network or storage APIs.

Feature support

score-compose supports as many Score features as possible, however there are certain parts that don't fit well in a local Docker case and are not supported:

Feature Support Impact
containers.*.resources.limits / containers.*.resources.requests none Limits will be validated but ignored. While the compose specification has some support for this, it is requires particular Docker versions that cannot be relied on. This should have no impact on Workload execution.
containers.*.livenessProbe / containers.*.readinessProbe none Probes will be validated but ignored. The Score specification only details K8s-like HTTP probes, but the compose specification only supports direct command execution. We cannot convert between the two reliably. This should have no impact on Workload execution. Tracked in #86.

Resource support

score-compose comes with out-of-the-box support for:

Type Class Params Output
environment default (none) ${KEY}
service-port default workload, port hostname, port
volume default (none) source
redis default (none) host, port, username, password
postgres default (none) host, port, name (aka database), username, password
mysql default (none) host, port, name (aka database), username, password
s3 default (none) endpoint, access_key_id, secret_key, bucket, with region="", aws_access_key_id=<access_key_id>, and aws_secret_key=<secret_key> for compatibility
dns default (none) host
route default host, path, port
amqp default (none) host, port, vhost, username, password
mongodb default (none) host, port, username, password, connection
kafka-topic default (none) host, port, name, num_partitions
elasticsearch default (none) host, port, username, password

These can be found in the default provisioners file. You are encouraged to write your own provisioners and add them to the .score-compose directory (with the .provisioners.yaml extension) or contribute them upstream to the default.provisioners.yaml file.

Installation

To install score-compose, follow the instructions as described in our installation guide. You will also need a recent version of Docker and the Compose plugin installed. Read more here.

Get started

NOTE: the following examples and guides relate to score-compose >= 0.11.0, check your version using score-compose --version and re-install if you're behind!

See the examples for more examples of using Score and provisioning resources:

  • 01-hello - a basic example of a Score Workload
  • 02-environment - an example of environment variables and the type: environment resource
  • 03-files - mounting local files into the running Workload
  • 04-multiple-workloads - examples of multiple containers and workloads together
  • 05-volume-mounts - an example of an "empty-dir" volume resource with type: volume
  • 06-resource-provisioning - detailed example and information about resource provisioning and the operation of the template:// and cmd:// provisioners
  • 07-overrides - details of how to override aspects of the input Score file and output Docker compose files
  • 08-service-port-resource - an example of using the service-port resource type to link between workloads
  • 09-dns-and-route - an example of using the dns and route resources to route http requests
  • 10-amqp-rabbitmq - an example the default amqp resource provisioner
  • 11-mongodb-document-database - an example the default mongodb resource provisioner
  • 12-mysql-database - an example of the default mysql resource provisioner
  • 13-kafka-topic - an example of the default kafka-topic resource provisioner
  • 14-elasticsearch - an example of the default elasticsearch resource provisioner

If you're getting started, you can use score-compose init to create a basic score.yaml file in the current directory along with a .score-compose/ working directory.

$ score-compose init --help
The init subcommand will prepare the current directory for working with score-compose and prepare any local
files or configuration needed to be successful.

A directory named .score-compose will be created if it doesn't exist. This file stores local state and generally should
not be checked into source control. Add it to your .gitignore file if you use Git as version control.

The project name will be used as a Docker compose project name when the final compose files are written. This name
acts as a namespace when multiple score files and containers are used.

Usage:
  score-compose init [flags]

Examples:

  # Define a score file to generate
  score-compose init --file score2.yaml

  # Or override the docker compose project name
  score-compose init --project score-compose2

  # Or disable the default score file generation if you already have a score file
  score-compose init --no-sample

  # Optionally loading in provisoners from a remote url
  score-compose init --provisioners https://raw.githubusercontent.com/user/repo/main/example.yaml

Flags:
  -f, --file string                The score file to initialize (default "./score.yaml")
  -h, --help                       help for init
      --no-sample                  Disable generation of the sample score file
  -p, --project string             Set the name of the docker compose project (defaults to the current directory name)
      --provisioner stringArray    A provisioners file to install. May be specified multiple times. Supports http://host/file, https://host/file, git-ssh://git@host/repo.git/file, git-https://host/repo.git/file and oci://[registry/][namespace/]repository[:tag|@digest][#file] formats.

Global Flags:
      --quiet           Mute any logging output
  -v, --verbose count   Increase log verbosity and detail by specifying this flag one or more times

Once you have a score.yaml file created, modify it by following this guide, and use score-compose generate to convert it into a Docker compose manifest:

The generate command will convert Score files in the current Score compose project into a combined Docker compose
manifest. All resources and links between Workloads will be resolved and provisioned as required.

By default this command looks for score.yaml in the current directory, but can take explicit file names as positional
arguments.

"score-compose init" MUST be run first. An error will be thrown if the project directory is not present.

Usage:
  score-compose generate [flags]

Examples:

  # Specify Score files
  score-compose generate score.yaml *.score.yaml

  # Regenerate without adding new score files
  score-compose generate

  # Provide overrides when one score file is provided
  score-compose generate score.yaml --override-file=./overrides.score.yaml --override-property=metadata.key=value

  # Publish a port exposed by a workload for local testing
  score-compose generate score.yaml --publish 8080:my-workload:80

  # Publish a port from a resource host and port for local testing, the middle expression is RESOURCE_ID.OUTPUT_KEY
  score-compose generate score.yaml --publish 5432:postgres#my-workload.db.host:5432

Flags:
      --build stringArray               An optional build context to use for the given container --build=container=./dir or --build=container={"context":"./dir"}
      --env-file string                 Location to store a skeleton .env file for compose - this will override existing content
  -h, --help                            help for generate
      --image string                    An optional container image to use for any container with image == '.'
  -o, --output string                   The output file to write the composed compose file to (default "compose.yaml")
      --override-property stringArray   An optional set of path=key overrides to set or remove
      --overrides-file string           An optional file of Score overrides to merge in
      --publish stringArray             An optional set of HOST_PORT:<ref>:CONTAINER_PORT to publish on the host system.

Global Flags:
      --quiet           Mute any logging output
  -v, --verbose count   Increase log verbosity and detail by specifying this flag one or more times

NOTE: The score-compose run command still exists but is hidden and should be considered deprecated as it does not support resource provisioning.

Using the --publish flag

score-compose installs all workloads and resource services into the compose docker network but does not publish ports on the host by default. To access ports inside the network, the user must either exec into a target container, run a new socat container with published ports, use a route resource that publishes "public" ports, or modify the compose.yaml directly.

The --publish flag on the generate command can be used to automatically add published ports to the services in the compose.yaml file in a safe and dynamic way. Note that this is an ephemeral flag not stored in the state file. As such it should be added to the last invocation of score-compose generate to avoid it being overridden by subsequent calls.

  • To publish a container port from a workload to the host, use --publish HOST_PORT:<workload>:CONTAINER_PORT.
  • To publish a a port from one of the resource services, use --publish HOST_PORT:<resource uid>.<output key>:CONTAINER_PORT. Examples of this are:
    • 15432:postgres#my-workload.res.host:5432 - host is the output on the postgres.default#my-workload.res Postgres resource that contains the service hostname.
    • 9001:s3.default#storage.service:9001 - service is the service name output on the s3.default#storage S3 resource.

This deprecates the use of the compose.score.dev/publish-port resource metadata annotation in most cases.

Testing

Run the tests using go test -v ./... -race. If you do not have docker CLI installed locally or want the tests to run faster, consider setting NO_DOCKER=true to skip any docker compose based validation during testing.

Get in touch

Learn how to connect and engage with our community here.

Contribution Guidelines and Governance

Our general contributor guidelines can be found in CONTRIBUTING.md. Please note that some repositories may have additional guidelines. For more information on our governance model, please refer to GOVERNANCE.md.

Documentation

You can find our documentation at docs.score.dev.

Roadmap

See Roadmap. You can submit an idea anytime.

License

License

FOSSA Status

Code of conduct

Contributor Covenant