Refactor EPG into shared engine with configurable TVJ channels

entrypoint.sh

@@ -3,11 +3,16 @@ set -eu
 
 mkdir -p /app/output
 UPDATE_INTERVAL="${UPDATE_INTERVAL:-6}"
+export UPDATE_INTERVAL
+UPDATE_INTERVAL="$(python -c 'import os; value = os.environ["UPDATE_INTERVAL"]; assert value.isascii() and value.isdigit() and int(value) > 0, "UPDATE_INTERVAL must be a positive integer (hours)"; print(int(value))')"
+# Fail fast on invalid channel/output configuration.
+python -c 'from epg.config import load; load()'
 
 ( while true; do
-    echo "$(date) - Updating TVJ EPG..."
-    python /app/tvj_epg.py
-    echo "$(date) - Sleeping for ${UPDATE_INTERVAL} hours..."
+    echo "$(date) - Updating EPG and playlist..."
+    if ! python -m epg.engine; then
+        echo "$(date) - Update failed; retrying after ${UPDATE_INTERVAL} hours." >&2
+    fi
     sleep "$((UPDATE_INTERVAL * 3600))"
   done
 ) &