feat: check whether orderer is a RAFT leader before starting app

Dockerfile

@@ -1,7 +1,12 @@
 FROM eclipse-temurin:11-jre-focal
 
+RUN apt-get update \
+    && apt-get install -y curl \
+    && rm -rf /var/lib/apt/lists/*  # Clean up to reduce image size
+
 WORKDIR /app
 
 COPY build/install/blocc-temp-humidity-app/ .
+COPY scripts/raft-leader-check.sh .
 
-ENTRYPOINT ["./bin/blocc-temp-humidity-app"]
+ENTRYPOINT ["./raft-leader-check.sh "]

scripts/raft-leader-check.sh

@@ -0,0 +1,31 @@
+#!/bin/bash
+
+retries=20
+
+while [[ $retries -gt 0 ]]; do
+    curl -s http://${FABRIC_ORDERER_ADDRESS}/metrics > /tmp/orderer_metrics 2> /dev/null
+
+    if [ $? -ne 0 ]; then
+        echo "Failed to fetch metrics from orderer. Retrying..."
+        ((retries--))
+        sleep 3
+        continue
+    fi
+
+    STATUS=$(grep 'consensus_etcdraft_is_leader' /tmp/orderer_metrics | grep -o '[0-1]$')
+
+    if [ "$STATUS" == "1" ]; then
+        echo "Orderer is RAFT leader. Starting blocc-temp-humidity-app..."
+        ./bin/blocc-temp-humidity-app  # Start the app here
+        break
+    else
+        echo "Orderer is not RAFT leader. Retrying..."
+        ((retries--))
+        sleep 3
+    fi
+done
+
+if [[ $retries -eq 0 ]]; then
+    echo "Failed to confirm RAFT leader status after several attempts."
+    exit 1
+fi