FastScore Configuration Syntax

The Connect service maintains the deployment-wide configuration. The configuration describes all service instances, the Pneumo properties, etc.

The standard representation of FastScore configuration uses YAML format. The semi-formal template for the configuration is given below:

fastscore:
  fleet:
    - api: model-manage
      host: ...
      port: ...
    - api: engine
    ...
  pneumo:
    type: REST (or kafka)
    ...
  db:
    type: mysql
    host: ...
    port: 3306
    username: ...
    password: ...

Use the following CLI command to set the FastScore configuration:

$ fastscore config set config.yaml

Note that the configuration can be set multiple time. The services are able to detect the change in the version of the configuration and act accordingly, e.g. use a different Kafka instance for Pneumo messages.

Specifying custom instance names

Fleet elements all have a name, which, by default, is the host name specified. However, custom names can be given:

fastscore:
  fleet:
    - api: model-manage
      name: Mr. Manager
      host: model-manage
      port: 8002
    - api: engine
      host: engine-1
      port: 8003
    - api: engine
      name: an explicitly named engine
      host: engine-2
      port: 8003

$ fastscore fleet
Name                        API           Health
--------------------------  ------------  --------
engine-1                    engine        ok
an explicitly named engine  engine        ok
Mr. Manager                 model-manage  ok

Using Docker Secrets to configure database username/password

It is possible to configure credentials in FastScore via Docker Secrets. To do so you must:

• Grant access to the secret to the relevant microservice.
• Reference the secret with “secret://…” syntax inside the YAML config file.

Three options for secret:// syntax

Relative path

secret://secret1

FastScore will look for secret1 in the default /run/secrets directory

Relative path OVERRIDE

set the env variable SECRET_PATH_ROOT to /some/other/directory

secret://secret2

FastScore will expect to find /some/other/directory/secret2

Absolute path

secret:///absolute/path/to/secret3

FastScore will look in /absolute/path/to for secret3

Note the three ‘/’, instead of the usual two.

In config.yaml

Where ‘foo’ is the name of the Docker Secret that contains the username, and ‘bar’ is the name of the Docker Secret that contains the password:

MySQL secrets:

db:
  type: mysql
  username: secret://foo
  password: secret://bar

Git secrets:

db:
  type: git
  username: secret://foo
  password: secret://bar

In Stream Descriptors

Kafka stream:

{
  "Transport": {
    "Type": "kafka",
    "Keytab": "secret://foo",
    "Principal": "secret://bar"
  }
}

Note: Authenticated Kafka streams requires that the krb5.conf be copied into the engine container at /etc/.

S3 stream:

{
  "Transport": {
    "Type": "S3",
    "AccessKeyID": "secret://foo",
    "SecretAccessKey": "secret://bar"
  }
}

Configuration Persistence

Upon startup, the Connect service checks for a FASTSCORE_CONFIG environment variable. If present, it uses the contents of this variable to set FastScore’s initial configuration.

FASTSCORE_CONFIG can be set right in a docker-compose file:

...
  connect: 
    image: local/connect
    ports: 
        - "8001:8001"
    stdin_open: true
    environment: 
       FASTSCORE_CONFIG: |
        fastscore: 
          fleet: 
            - api: model-manage
              host: model-manage
              port: 8002
            - api: engine
              host: engine-1
              port: 8003
            - api: engine
              host: engine-2
              port: 8003

          db: 
            type: mysql
            host: database
            port: 3306
            username: root
            password: root

          pneumo: 
            type: kafka
            bootstrap: 
              - kafka:9092
            topic: notify
    tty: true
    networks: 
      - fsnet
...