Interface for the message publishing through Rambla.

Rambla maintains connection pools with Finitomata.Pool for each service.

The typical config for Rambla service follows the pattern introduced by AMQP library:

‹service›: [
  connections: [
    ‹connection_name›: [‹key_1›: ‹value_1›, …]
  ],
  channels: [
    ‹channel_name›: [
      connection: ‹connection_name›,
      options: [‹key_1›: ‹value_1›, …]
    ]
  ]
]

Additional option, one might pass to the channel config, would be explicit handlers for failures and success calls (by default the former prints the warning and retries until the maximum count of retries reached, and then calls on_fatal/2 callback, and the latter logs a debug message.)

  channels: [
    chan_1: [
      connection: :conn_1,
      options: [
        callbacks: [
          on_success: fn result -> IO.inspect(result, label: "on_success") && :ok end]
        ]]]]

To start pools, simply embed Rambla into the supervision tree, it’d start a supervisor with children for all the configured services.

The configuration of the service implies all the Rambla’s code for it will be compiled, but the dependency itself must be added to the deps section of the Mix.Project file.

The excerpt from the Rambla.MixProject itself follows

  # optional backends
  {:amqp, "~> 3.0", optional: true},
  {:redix, "~> 1.0", optional: true},
  {:pillar, "~> 0.39", optional: true},
  {:gen_smtp, "~> 0.4 or ~> 1.0", optional: true},
  {:telemetria, "~> 0.4 or ~> 1.0", optional: true},

  # s3
  {:ex_aws, "~> 2.1", optional: true},
  {:ex_aws_s3, "~> 2.0", optional: true},
  {:ex_aws_sts, "~> 2.0", optional: true},
  {:hackney, "~> 1.9", optional: true},
  {:sweet_xml, "~> 0.6", optional: true},
  {:configparser_ex, "~> 4.0", optional: true},

Channel names are used across connections to publish messages. Rambla.publish(:channel_1, message) would publish the message to all channels named channel_1.