Bluez.DBus (bluez v0.1.0)

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Shared helpers for outbound D-Bus method calls to org.bluez over a rebus connection, used by Bluez.Client (passive scanning) and Bluez.Gatt (active connections).

The rebus connection correlates in-flight calls by serial and replies via GenServer.reply/2, so concurrent calls on one connection don't serialize — a slow Device1.Connect does not block a ReadValue to another device. The timeout here is purely the caller's patience (GenServer.call/3 exit, surfaced as {:error, {:exit, ...}}).

Callers beware: these block the calling process for up to timeout. Call from a Task (never from a GenServer's own loop) for anything that can be slow — Connect can take ~25 s, GATT reads up to the ATT timeout.

Summary

Functions

add_match(conn, rule)

Install a bus-side match rule so the daemon routes matching signals to this connection (rebus installs none by itself).

call(conn, path, interface, member, signature, body, timeout \\ 5000)

Synchronous method call to org.bluez → {:ok, reply_body} | {:error, reason}.

call_to(conn, destination, path, interface, member, signature, body, timeout \\ 5000)

Like call/7 but to an arbitrary bus name. call/7 is this with destination: "org.bluez"; Bluez.BlueAlsa uses it to reach org.bluealsa over the same kind of connection. Same error normalization.

get_managed_objects(conn, timeout \\ 5000)

Fetch org.bluez's full object tree (ObjectManager.GetManagedObjects).

Functions

add_match(conn, rule)

@spec add_match(pid(), String.t()) :: term()

Install a bus-side match rule so the daemon routes matching signals to this connection (rebus installs none by itself).

call(conn, path, interface, member, signature, body, timeout \\ 5000)

@spec call(pid(), String.t(), String.t(), String.t(), String.t(), list(), timeout()) ::
  {:ok, list()} | {:error, term()}

Synchronous method call to org.bluez → {:ok, reply_body} | {:error, reason}.

Pass signature: "" for argument-less members. Errors are normalized: a D-Bus error reply yields {:error, error_name}, a raise yields {:error, exception}, and a GenServer.call timeout / dead connection yields {:error, {:exit, reason}} (exits are caught, not propagated).

call_to(conn, destination, path, interface, member, signature, body, timeout \\ 5000)

@spec call_to(
  pid(),
  String.t(),
  String.t(),
  String.t(),
  String.t(),
  String.t(),
  list(),
  timeout()
) :: {:ok, list()} | {:error, term()}

Like call/7 but to an arbitrary bus name. call/7 is this with destination: "org.bluez"; Bluez.BlueAlsa uses it to reach org.bluealsa over the same kind of connection. Same error normalization.

get_managed_objects(conn, timeout \\ 5000)

@spec get_managed_objects(pid(), timeout()) :: {:ok, list()} | {:error, term()}

Fetch org.bluez's full object tree (ObjectManager.GetManagedObjects).