Fix Docker builds in Gitea runner with proper Docker-in-Docker detection

- Use 'docker info' instead of 'command -v docker' for reliable detection
- Add 30-second wait for Docker daemon startup (for DinD startup delay)
- Improve Docker build step with better error handling
- Build Docker images when available, skip gracefully if not
- Add comprehensive GITEA_RUNNER_DOCKER.md setup guide
- Document Docker socket mounting for runners
- Include troubleshooting and complete docker-compose example

.gitea/workflows/release.yml

@@ -160,15 +160,22 @@ jobs:
 
       - name: Check Docker availability
         run: |
-          if ! command -v docker &> /dev/null; then
-            echo "⚠️  Docker is not available on this runner"
-            echo "Docker images will not be built. To enable Docker builds:"
-            echo "1. Install Docker on the runner machine"
-            echo "2. Ensure the runner has permission to use Docker"
-            echo "See GITEA_SETUP.md for more information"
-            exit 0
-          fi
-          docker --version
+          # Wait for Docker daemon to be ready (Docker-in-Docker)
+          echo "Waiting for Docker daemon..."
+          MAX_ATTEMPTS=30
+          ATTEMPT=0
+          while [ $ATTEMPT -lt $MAX_ATTEMPTS ]; do
+            if docker info &>/dev/null; then
+              echo "✓ Docker is ready"
+              docker --version
+              exit 0
+            fi
+            ATTEMPT=$((ATTEMPT + 1))
+            echo "Attempt $ATTEMPT/$MAX_ATTEMPTS - Docker not ready yet, waiting..."
+            sleep 1
+          done
+          echo "⚠️  Warning: Docker daemon is not available"
+          echo "Docker images will not be built"
 
       - name: Generate version
         id: version
@@ -182,15 +189,17 @@ jobs:
 
       - name: Build Docker images
         run: |
-          if ! command -v docker &> /dev/null; then
-            echo "Docker not available, skipping Docker image build"
+          # Check if Docker is available
+          if ! docker info &>/dev/null; then
+            echo "⚠️  Docker daemon is not available, skipping Docker image build"
+            echo "Binary builds were completed successfully"
             exit 0
           fi
           
           mkdir -p /tmp/docker-images
           
           echo "Building server image..."
-          docker build -t nerd-monitor-server:${{ env.version }} -f Dockerfile.server .
+          docker build -t nerd-monitor-server:${{ env.version }} -f Dockerfile.server . 2>&1
           if [ $? -eq 0 ]; then
             docker save nerd-monitor-server:${{ env.version }} -o /tmp/docker-images/nerd-monitor-server-${{ env.version }}.tar
             echo "✓ Server image built and saved"
@@ -200,7 +209,7 @@ jobs:
           fi
           
           echo "Building agent image..."
-          docker build -t nerd-monitor-agent:${{ env.version }} -f Dockerfile.agent .
+          docker build -t nerd-monitor-agent:${{ env.version }} -f Dockerfile.agent . 2>&1
           if [ $? -eq 0 ]; then
             docker save nerd-monitor-agent:${{ env.version }} -o /tmp/docker-images/nerd-monitor-agent-${{ env.version }}.tar
             echo "✓ Agent image built and saved"
@@ -210,7 +219,7 @@ jobs:
           fi
           
           echo ""
-          echo "Docker images built:"
+          echo "Docker images built successfully:"
           ls -lh /tmp/docker-images/
 
       - name: Upload Docker images to release