add watchdog / add minimal mode (#209)

* add watchdog

possible workaround for
#168

* add PIAWARE_MINIMAL mode without maps

README.md

@@ -455,6 +455,7 @@ Use only with `RECEIVER_TYPE=relay`.
 | `BEASTPORT`              | a port number    | Specify the TCP port number of the external BEAST protocol provider. | `30005` |
 | `MLAT_RESULTS_BEASTHOST` | a hostname or IP | Specify an external host where MLAT results should be sent.          |         |
 | `MLAT_RESULTS_BEASTPORT` | a port number    | Specify the TCP port number where MLAT results should be sent.       | `30104` |
+| `PIAWARE_MINIMAL`        | true or false    | Minimal feed configuration without maps                              | `false` |
 
 ### Receiver Configuration (978MHz)
 

rootfs/etc/s6-overlay/s6-rc.d/watchdog/run

@@ -0,0 +1,2 @@
+#!/bin/sh
+exec /etc/s6-overlay/scripts/watchdog

rootfs/etc/s6-overlay/s6-rc.d/watchdog/type

@@ -0,0 +1 @@
+longrun

rootfs/etc/s6-overlay/scripts/01-piaware

@@ -1,5 +1,7 @@
 #!/command/with-contenv bash
-# shellcheck shell=bash
+# shellcheck shell=bash disable=SC1091,2154
+
+source /scripts/common
 
 # Remove existing piaware config
 rm /etc/piaware.conf > /dev/null 2>&1 || true
@@ -54,7 +56,11 @@ piaware-config mlat-results "${MLAT_RESULTS:-yes}"
 
 # If a BEASTHOST is specified
 if [[ -n "$BEASTHOST" ]]; then
-  piaware-config receiver-type "relay"
+  if chk_enabled "${PIAWARE_MINIMAL}"; then
+    piaware-config receiver-type "other"
+  else
+    piaware-config receiver-type "relay"
+  fi
   piaware-config receiver-host "$BEASTHOST"
   piaware-config receiver-port "${BEASTPORT:-30005}"
 
@@ -79,10 +85,16 @@ elif [[ "$UAT_RECEIVER_TYPE" == "rtlsdr" ]]; then
 
 fi
 
+MLAT_RESULTS_STRING="beast,listen,30105 ext_basestation,listen,30106 "
+if ! chk_enabled "${PIAWARE_MINIMAL}"; then
+    MLAT_RESULTS_STRING+="beast,connect,localhost:30104 "
+fi
+
 # If MLAT_RESULTS_BEAST_CONNECT is specified
 if [[ -n "$MLAT_RESULTS_BEASTHOST" ]]; then
-  piaware-config mlat-results-format "beast,connect,localhost:30104 beast,listen,30105 ext_basestation,listen,30106 beast,connect,${MLAT_RESULTS_BEASTHOST}:${MLAT_RESULTS_BEASTPORT:-30104}"
+    MLAT_RESULTS_STRING+="beast,connect,${MLAT_RESULTS_BEASTHOST}:${MLAT_RESULTS_BEASTPORT:-30104} "
 fi
+piaware-config mlat-results-format "${MLAT_RESULTS_STRING}"
 
 # Create log dir for piaware
 mkdir -p /var/log/piaware

rootfs/etc/s6-overlay/scripts/beast-splitter

@@ -8,6 +8,9 @@ source /scripts/common
 if [[ -z "$BEASTHOST" ]]; then
     stop_service
 fi
+if chk_enabled "${PIAWARE_MINIMAL}"; then
+    stop_service
+fi
 
 # Prepare beast-splitter command line
 BEASTSPLITTER_BIN="/usr/local/bin/beast-splitter"

rootfs/etc/s6-overlay/scripts/dump1090

@@ -17,6 +17,9 @@ fi
 if [[ -z "$RUN_DUMP1090" ]]; then
     stop_service
 fi
+if chk_enabled "${PIAWARE_MINIMAL}"; then
+    stop_service
+fi
 
 mkdir -p /run/dump1090-fa
 

rootfs/etc/s6-overlay/scripts/skyaware978

@@ -17,6 +17,9 @@ fi
 if [[ -z "$RUN_SKYAWARE978" ]]; then
     stop_service
 fi
+if chk_enabled "${PIAWARE_MINIMAL}"; then
+    stop_service
+fi
 
 mkdir -p /run/skyaware978
 

rootfs/etc/s6-overlay/scripts/watchdog

@@ -0,0 +1,22 @@
+#!/command/with-contenv bash
+# shellcheck shell=bash disable=SC1091,2154
+
+source /scripts/common
+
+# checking every 60 seconds
+sleep 60
+
+# check if the current date is larger than the expiry field of the status json
+if (( $(date +%s) * 1000 > $(grep -o -E -e '(expiry)" *: ([0-9]+)' /run/piaware/status.json | awk '{print $3}') )); then
+    # current date being larger means piaware is hanging, kill it
+    "${s6wrap[@]}" echo "piaware is not updating /run/piaware/status.json, sending SIGKILL"
+    pkill -9 piaware
+fi
+
+
+# make sure /var/log/piaware/current doesn't grow too large
+if (( $(wc -l < /var/log/piaware/current) > 400 )); then
+    keep=$(tail -n200 /var/log/piaware/current)
+    truncate -s 0 /var/log/piaware/current
+    cat >> /var/log/piaware/current <<< "$keep"
+fi