wasd, service↔machine discovery

Usage

• This service ingests Cassandra rings and DNS records across multiple sites at a regular interval, then exposes information about hosts and services.

• One can ask what a host does, optionally for which sites; which hosts in a site offer a service; which hosts offer a service for a site.

• Queries follow a simple REST API documented in API. Answers are serialized in JSON.

• The configuration is handled by typesafe's config; we recommend putting an application.conf in the classpath of the service.

Status

• Our command line clients are not ready for public distribution.

• Public documentation is lacking.

• Patches are welcome.

Example configuration

Server { RefreshRate: 60s }
Sites {
  'london.example.com.' {
    Aliases = [ 'lon', 'london', 'london.example.com' ]
  }
  'paris.example.com.' {
    Aliases = [ 'par', 'paris', 'paris.example.com' ]
  }
}
Services {
  puppet {
    Records = [
      {
        Type: 'A', // round-robin
        Name: 'puppet',
      }
    ]
  }
  user_db {
    Records = [
      {Type: 'CNAME', Name: '_user_db_master._tcp'},
      {Type: 'CNAME', Name: '_user_db_slave._tcp'}
    ]
    Contacts = {
        Ops = [
            {Type: person, Email: "user1@example.com"},
            {Type: person, Email: "user2@example.com"},
        ]
    }
  }
  user_contents {Cassandra = [{Type: SRV, Name: _user_contents._cassandra}]}
}