Discover Datum container IP at runtime

docker-compose.yml

@@ -1,7 +1,7 @@
 # gashboard — deploy as a Portainer Stack on the same Umbrel host that runs Datum.
 #
-# Join Datum's app network so the API can reach Datum by its stable Compose
-# service DNS name instead of a changing container IP.
+# Uses the Docker socket to discover Datum's current IP on Umbrel's shared
+# Docker network, avoiding stale hard-coded container IPs.
 
 services:
   gashboard:
@@ -21,9 +21,11 @@ services:
       PORT: "1337"
       LOG_LEVEL: "${LOG_LEVEL:-info}"
       CORS_ORIGIN: "${CORS_ORIGIN:-}"
-      # Reach the Datum gateway container through Docker DNS on Datum's app
-      # network. This avoids hard-coding Datum's changing container IP.
-      DATUM_URL: "${DATUM_URL:-http://datum:21000}"
+      # Fallback URL. With DATUM_DOCKER_* set below, the API resolves Datum's
+      # current container IP before polling.
+      DATUM_URL: "${DATUM_URL:-http://datum_datum_1:21000}"
+      DATUM_DOCKER_CONTAINER: "${DATUM_DOCKER_CONTAINER:-datum_datum_1}"
+      DATUM_DOCKER_NETWORK: "${DATUM_DOCKER_NETWORK:-umbrel_main_network}"
       DATUM_ADMIN_USER: "${DATUM_ADMIN_USER:-admin}"
       DATUM_ADMIN_PASSWORD: "${DATUM_ADMIN_PASSWORD?must be set}"
       DATUM_POLL_INTERVAL_MS: "${DATUM_POLL_INTERVAL_MS:-5000}"
@@ -31,17 +33,13 @@ services:
       NOSTR_ALLOWED_NPUBS: "${NOSTR_ALLOWED_NPUBS?must be set}"
       JWT_SECRET: "${JWT_SECRET?must be set}"
       JWT_TTL_SECONDS: "${JWT_TTL_SECONDS:-86400}"
-    ports:
-      - "${PORT:-1337}:1337"
-    networks:
-      - datum_default
+    network_mode: host
+    user: "0:0"
+    volumes:
+      - /var/run/docker.sock:/var/run/docker.sock:ro
     healthcheck:
       test: ["CMD", "wget", "-qO-", "http://127.0.0.1:1337/healthz"]
       interval: 30s
       timeout: 5s
       retries: 3
       start_period: 15s
-
-networks:
-  datum_default:
-    external: true