Configuration

Service Catalog is configured using a JSON configuration file, path to which is provided to the SC via -conf flag. By default, the service looks for a configuration file at: conf/service-catalog.json

All configuration fields (except for arrays of objects) can be overridden using environment variables. Below are few examples:

• SC_STORAGE_TYPE=leveldb
• SC_MQTT_CLIENT_BROKERURI=tcp://iot.linksmart.eu:1883
• SC_MQTT_CLIENT_REGTOPICS="a/b,a/c"
• ❌ SC_MQTT_ADDITIONALCLIENTS setting array of objects is not supported with environment variables

Configuration File

A sample configuration file is available at service-catalog.json.

{
  "description": "string",
  "dnssdEnabled": "boolean",
  "storage": {
    "type": "string",
    "dsn": "string"
  },
  "http" : {
    "bindAddr": "string",
    "bindPort": "int"
  }, 
  "mqtt":{
    "client": {
        "disabled": "bool",
        "brokerID": "string",
        "brokerURI":"string",
        "regTopics": ["string"],
        "willTopics": ["string"],
        "qos": "int",
        "username": "",
        "password": ""
    },
    "additionalClients": [],
    "commonRegTopics":  ["string"],
    "commonWillTopics": ["string"],
    "topicPrefix": "string"
  },
  "auth": {
        "enabled": "bool",
        "provider": "string",
        "providerURL": "string",
        "serviceID": "string",
        "basicEnabled": "bool",
        "authorization": {}
    }
}

where

• description is a human-readable description for the SC
• dnssdEnabled is a flag enabling DNS-SD advertisement of the catalog on the network
• storage is the configuration of the storage backend
  • type is the type of the backend (supported backends are memory and leveldb)
  • dsn is the Data Source Name for storage backend (ignored for memory, "file:///path/to/ldb" for leveldb)
• http is the configuration of HTTP API
  • bindAddr is the bind address which the server listens on
  • bindPort is the bind port
• mqtt is the configuration of MQTT API
  • client is the configuration for the main MQTT client
    • disabled is a boolean flag disabling/enabling the mqtt client
    • brokerID is the service ID of the broker (Optional)
    • brokerURI is the URL of the broker
    • regTopics is an array of topics that the client should subscribe to for addition/update of services
      • Example: "regTopics": ["topic/reg/+"]
      • While publishing a service registration message over this topic, '+' should be replaced by id of the service to be added/updated. id passed in message payload takes precedence over id in the topic
        • E.g., mosquitto_pub -h localhost -p 1883 -t 'topic/reg/custom_id1' -f ./service_object.json
    • willTopics is an array of will topics that the client should subscribe to for removal of services (Optional in case TTL is used for registration)
      • Example: "willTopics": ["topic/dereg/+"]
      • While publishing a service deregistration message over this topic, '+' should be replaced by id of the service to be removed
        • E.g., mosquitto_pub -h localhost -p 1883 -t 'topic/dereg/custom_id1' -m 'something'
    • qos is the MQTT Quality of Service (QoS) for all reg and will topics
    • username is username for MQTT client
    • password is the password for MQTT client
  • additionalClients is an array of additional brokers objects.
  • commonRegTopics is an array of topics that all clients should subscribe to for addition/update of services (Optional)
    • Example: same as the example for 'regTopics' above
  • commonWillTopics is an array of will topic that the client should subscribe to for removal of services (Optional in case commonRegTopics not used or TTL is used for registration)
    • Example: same as the example for 'willTopics' above
  • **topicPrefix** is the string describing the prefix of service announcement topics
• auth is the Authentication configuration
  • enabled is a boolean flag enabling/disabling the authentication
  • provider is the name of a supported auth provider
  • providerURL is the URL of the auth provider endpoint
  • serviceID is the ID of the service in the authentication provider (used for validating auth tokens provided by the clients)
  • basicEnabled is a boolean flag enabling/disabling the Basic Authentication
  • authorization - optional, see authorization configuation