lws minimal dbus server

build

Using libdbus requires additional non-default include paths setting, same as is necessary for lws build described in ./lib/roles/dbus/README.md

CMake can guess one path and the library name usually, see the README above for details of how to override for custom libdbus and cross build.

Fedora example:

$ cmake .. -DLWS_DBUS_INCLUDE2="/usr/lib64/dbus-1.0/include"
$ make

Ubuntu example:

$ cmake .. -DLWS_DBUS_INCLUDE2="/usr/lib/x86_64-linux-gnu/dbus-1.0/include"
$ make

usage

By default the minimal server listens using its own abstract unix socket at unix:abstract=org.libwebsockets.test.

You can also run it instead as a participant on the session bus, without its own unix socket, by giving --session.

Examples using the default private abstract unix socket

 $ ./lws-minimal-dbus-server
[2018/10/03 07:08:02:6448] USER: LWS minimal dbus server
[2018/10/03 07:08:02:6693] NOTICE: Creating Vhost 'default' port 0, 1 protocols, IPv6 off
...

You can communicate with the dbus server over its private abstract socket using, eg

$ gdbus introspect --address unix:abstract=org.libwebsockets.test --dest org.libwebsockets.test --object-path /org/libwebsockets/test
node /org/example/TestObject {
  interface org.freedesktop.DBus.Introspectable {
    methods:
      Introspect(out s data);
    signals:
    properties:
  };
  interface org.freedesktop.DBus.Properties {
    methods:
      Get(in  s interface,
...

$ gdbus call --address unix:abstract=org.libwebsockets.test --dest org.libwebsockets.test --object-path /org/libwebsockets/test --method org.libwebsockets.test.Echo HELLO
('HELLO',)

Examples using the DBUS session bus

 $ ./lws-minimal-dbus-server --session
[2018/10/03 07:08:02:6448] USER: LWS minimal dbus server
[2018/10/03 07:08:02:6693] NOTICE: Creating Vhost 'default' port 0, 1 protocols, IPv6 off
...

You can communicate with the dbus server over the session bus using, eg

$ gdbus introspect --session --dest org.libwebsockets.test --object-path /org/libwebsockets/test
node /org/example/TestObject {
  interface org.freedesktop.DBus.Introspectable {
    methods:
      Introspect(out s data);
    signals:
    properties:
  };
  interface org.freedesktop.DBus.Properties {
    methods:
      Get(in  s interface,
...

$ gdbus call --session --dest org.libwebsockets.test --object-path /org/libwebsockets/test --method org.libwebsockets.test.Echo HELLO
('HELLO',)