document the output parameter

docs/configuring.rst

@@ -134,6 +134,10 @@ Other values can be set as ``method``:
    connection by generating different data each time it's called.
    This should only be used for Showergel's unit tests.
 
+You can also add a line stating ``ouput = "identifier"`` to force Showergel to
+get its "Now playing" information from the output having ``id="identifier"``
+in your Liquidsoap script (see :ref:`liq_current`).
+
 ``[metadata_log]``
 ------------------
 

docs/liquidsoap.rst

@@ -31,11 +31,12 @@ your existing script (it also contain a few Liquidsoap tricks!).
 
 Sections below discuss implementation details on integrating each Showergel feature.
 
+.. _liq_current:
 
 Display/skip current track
 --------------------------
 
-You just need to enable `Liquidsoap's telnet server <https://www.liquidsoap.info/doc-2.0.0/server.html>`_.
+You need to enable `Liquidsoap's telnet server <https://www.liquidsoap.info/doc-2.0.0/server.html>`_.
 For example:
 
 .. code-block:: ocaml
@@ -55,6 +56,10 @@ be careful to set a different ``port`` for each one.
     This would open your Liquidsoap instance to the Internet,
     and someone might connect and mess up your programs.
 
+**If your script has multiple outputs**, ensure the main one has an identifier
+by setting its ``id="identifier"`` parameter.
+This identifier should be copied as ``output`` in the :ref:`configuration_liquidsoap` section.
+
 .. _liq_metadata:
 
 Logging metadata

showergel/commands/install.py

@@ -65,6 +65,10 @@
 host = "127.0.0.1"
 port = 1234
 
+# to ensure Showergel gets its "Now playing" information from the correct output,
+# you can add the following line with that output's `id`:
+# output = "id"
+
 ############# Logging configuration ##########
 [logging]
 version = 1