NebulaAPI.Server (NebulaAPI v0.5.1)

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Per-application supervisor for NebulaAPI workers.

One NebulaAPI.Server lives in the supervision tree of each OTP application that owns modules using NebulaAPI (wire it in with use NebulaAPI.Server + nebula_api_server/0). It is given app_module: — a module belonging to that app — from which it resolves the owning app, lists its modules, and keeps only those that:

  1. carry the persisted :nebula_api marker (i.e. they use NebulaAPI), and
  2. have at least one method compiled as local on this node,

and starts one NebulaAPI.APIServer.Worker per retained module. Each worker joins the cluster-wide :pg group so remote nodes can route to it.

Living inside the app's own tree is what makes the lifecycle correct: when the app stops or crashes, this supervisor (and its workers) go down with it and :pg drops the entries. The serving set is discovered from the app's compiled modules.

Summary

Functions

__using__(opts)

Brings the nebula_api_server/0 macro into scope, plus the NebulaAPI.AST macros (on_nebula_nodes, call_on_*). For the host module — typically the app's Application — that wires the per-app server into its supervision tree.

child_spec(init_arg)

Returns a specification to start this module under a supervisor.

nebula_api_server()

Expands to a child spec for NebulaAPI.Server, to be placed in the supervision tree of an OTP application that owns modules using NebulaAPI.

start_link(opts)

Functions

__using__(opts)

(macro)

Brings the nebula_api_server/0 macro into scope, plus the NebulaAPI.AST macros (on_nebula_nodes, call_on_*). For the host module — typically the app's Application — that wires the per-app server into its supervision tree.

Unlike use NebulaAPI, this does not register the defapi bookkeeping (:nebula_local_api_methods, :nebula_remote_api_methods, the :nebula_api marker) nor validate self_node — the host module has no defapi of its own, so none of that applies. Use use NebulaAPI only on modules that actually define defapi endpoints.

child_spec(init_arg)

Returns a specification to start this module under a supervisor.

See Supervisor.

nebula_api_server()

(macro)

Expands to a child spec for NebulaAPI.Server, to be placed in the supervision tree of an OTP application that owns modules using NebulaAPI.

Brought into scope by use NebulaAPI.Server. It expands at the call site, so __MODULE__ is the host module (typically the app's Application), which belongs to the consumer's OTP app — all the server needs to resolve the app and, at runtime, discover its modules, keep the ones with local methods on this node, and start a worker for each. Because the server lives inside the app's own tree, the worker lifecycle is correct for free: app stops or crashes → server and workers die with it, :pg drops the entries.

defmodule MyApp.Application do
  use Application
  use NebulaAPI.Server

  def start(_type, _args) do
    Supervisor.start_link([nebula_api_server()], strategy: :one_for_one, name: MyApp.Sup)
  end
end

start_link(opts)