Implement ONEVENT_COMMAND and ONEVENT_POST_ENDPOINT config options (#92)

* add ON_EVENT configuration option that controls --onevent flag

* ONEVENT_COMMAND instead of ON_EVENT flag

* add ONEVENT_POST_ENDPOINT config option

* adjust documentation

Author: QuadratClown

Dockerfile

@@ -97,6 +97,9 @@ ENV AUDIO_GID=""
 ENV PARAMETER_PRIORITY=""
 ENV LOG_COMMAND_LINE=""
 
+ENV ONEVENT_COMMAND=""
+ENV ONEVENT_POST_ENDPOINT=""
+
 VOLUME /data/cache
 VOLUME /data/system-cache
 VOLUME /user/config
@@ -112,6 +115,7 @@ RUN which librespot
 COPY app/bin/run-librespot.sh /app/bin/
 COPY app/bin/read-file.sh /app/bin/
 COPY app/bin/get-value.sh /app/bin/
+COPY app/bin/post-event-data.sh /app/bin/
 
 RUN chmod u+x /app/bin/*.sh
 

README.md

@@ -107,6 +107,8 @@ PUID||Set this value the the user which should run the application, defaults to
 PGID||Set this value the the user which should run the application, defaults to `1000` if not set when using the `pulseaudio` backend
 AUDIO_GID||Specifies the gid for the group `audio`, it is required if you want to use, e.g., the `alsa` backend in user mode. Refer to [this page](https://github.com/GioF71/squeezelite-docker/blob/main/doc/example-alsa-user-mode.md) from my squeezelite-docker repository for more details.
 PARAMETER_PRIORITY||Where to look for a parameter first: `env` or `file`. For example, the `credentials.txt` file compared to `SPOTIFY_USERNAME` and `SPOTIFY_PASSWORD` environment variables. Defaults to `file`, meaning that each file is considered if it exists and if it contains the required values.
+ONEVENT_COMMAND||Specifies the name of a user defined script/executable that will be executed whenever a player event occurs. User defined scripts must be mounted to the `/userscripts/` folder and be made executable via `chmod u+x`. Internally maps to the `--onevent` flag of `librespot`. More info about usage can be found in [librespot's player event handler](https://github.com/librespot-org/librespot/blob/dev/src/player_event_handler.rs).
+ONEVENT_POST_ENDPOINT||Send a `POST` request with event data to the specified endpoint URL whenever a player event occurs. Request body is `json` encoded and contains all available fields specified by the [librespot's player event handler](https://github.com/librespot-org/librespot/blob/dev/src/player_event_handler.rs). Will be ignored if `ONEVENT_COMMAND` is set.
 LOG_COMMAND_LINE||Set to  `Y` or `y` to enable, `N` or `n` to disable. Defaults to `Y`.
 
 ### Volumes

app/bin/post-event-data.sh

@@ -0,0 +1,51 @@
+#!/bin/bash
+
+# read url input parameter
+while [ $# -gt 0 ]; do
+  case "$1" in
+    --url=*)
+      endpoint_url="${1#*=}"
+      ;;
+  esac
+  shift
+done
+
+# post current event data the given endpoint URL
+curl -X POST \
+-s \
+-H "Content-Type: application/json" \
+-d '{
+    "PLAYER_EVENT": "'"$PLAYER_EVENT"'",
+    "TRACK_ID": "'"$TRACK_ID"'",
+    "URI": "'"$URI"'",
+    "NAME": "'"$NAME"'",
+    "COVERS": "'"${COVERS//$'\n'/,}"'",
+    "LANGUAGE": "'"$LANGUAGE"'",
+    "DURATION_MS": "'"$DURATION_MS"'",
+    "NAME": "'"$NAME"'",
+    "IS_EXPLICIT": "'"$IS_EXPLICIT"'",
+    "ITEM_TYPE": "'"$ITEM_TYPE"'",
+    "ARTISTS": "'"$ARTISTS"'",
+    "ALBUM_ARTISTS": "'"$ALBUM_ARTISTS"'",
+    "ALBUM": "'"$ALBUM"'",
+    "NUMBER": "'"$NUMBER"'",
+    "DISC_NUMBER": "'"$DISC_NUMBER"'",
+    "DESCRIPTION": "'"$DESCRIPTION"'",
+    "PUBLISH_TIME": "'"$PUBLISH_TIME"'",
+    "SHOW_NAME": "'"$SHOW_NAME"'",
+    "POSITION_MS": "'"$POSITION_MS"'",
+    "CONNECTION_ID": "'"$CONNECTION_ID"'",
+    "USER_NAME": "'"$USER_NAME"'",
+    "CLIENT_ID": "'"$CLIENT_ID"'",
+    "CLIENT_NAME": "'"$CLIENT_NAME"'",
+    "CLIENT_BRAND_NAME": "'"$CLIENT_BRAND_NAME"'",
+    "CLIENT_MODEL_NAME": "'"$CLIENT_MODEL_NAME"'",
+    "VOLUME": "'"$VOLUME"'",
+    "SHUFFLE": "'"$SHUFFLE"'",
+    "REPEAT": "'"$REPEAT"'",
+    "AUTO_PLAY": "'"$AUTO_PLAY"'",
+    "FILTER": "'"$FILTER"'",
+    "SINK_STATUS": "'"$SINK_STATUS"'"
+}' \
+$endpoint_url
+

app/bin/run-librespot.sh

@@ -286,6 +286,15 @@ if [ "${PASSTHROUGH^^}" = "Y" ]; then
     CMD_LINE="$CMD_LINE --passthrough"
 fi
 
+# parse onevent related config options
+# if both onevent options are set,
+# the user defined script takes precedence
+if [[ -n "$ONEVENT_COMMAND" ]]; then
+    CMD_LINE="$CMD_LINE --onevent '/userscripts/$ONEVENT_COMMAND'"
+elif [[ -n "$ONEVENT_POST_ENDPOINT" ]]; then
+    CMD_LINE="$CMD_LINE --onevent '/app/bin/post-event-data.sh --url=$ONEVENT_POST_ENDPOINT'"
+fi
+
 if [[ -z "${LOG_COMMAND_LINE}" || "${LOG_COMMAND_LINE^^}" = "Y" ]]; then
     ur=$(printf '*%.0s' $(seq 1 ${#SPOTIFY_USERNAME}))
     pr=$(printf '*%.0s' $(seq 1 ${#SPOTIFY_PASSWORD}))