container/inspect

When to Use

• Pre-upgrade check: Inspect a running container to retrieve its current environment variables and port bindings before replacing it with a new version.
• Failure diagnosis: After a container stops unexpectedly, inspect it to get the ExitCode, FinishedAt timestamp, and Error message.
• IP discovery: Retrieve the container's internal IP address for use in internal service-to-service communication or network rule updates.
• Config drift detection: Compare the running container's Config object against an expected specification stored in a workflow variable to detect unauthorized changes.
• Mount verification: Confirm that required volumes are attached and mounted at the expected paths before starting a dependent service.

Configuration

Connection Fields

Operation Fields

Sample Configuration

{
  "resource": "container",
  "operation": "inspect",
  "ContainerId": "api-service",
  "connection": {
    "dockerHost": "unix:///var/run/docker.sock",
    "connectionType": "unixsocket",
    "timeoutSeconds": 30
  }
}

Validation Errors

Output

Success Port

Error Port

On failure, the error port receives errorCode, message, resource, and operation. A NOT_FOUND error is expected when checking for a container that may or may not exist — handle it with a conditional branch.

Sample Output

{
  "container": {
    "Id": "a1b2c3d4e5f67890abcdef1234567890abcdef1234567890abcdef1234567890",
    "Name": "/api-service",
    "Created": "2024-01-01T08:00:00.000Z",
    "State": {
      "Status": "running",
      "Running": true,
      "Paused": false,
      "Restarting": false,
      "Pid": 12345,
      "ExitCode": 0,
      "StartedAt": "2024-01-01T08:00:05.123Z",
      "FinishedAt": "0001-01-01T00:00:00Z",
      "Error": ""
    },
    "Config": {
      "Image": "myapp:v2.1.0",
      "Env": ["NODE_ENV=production", "PORT=8080", "DB_HOST=db-service"],
      "Cmd": ["node", "server.js"],
      "Labels": {
        "com.bizfirst.env": "production",
        "com.bizfirst.version": "2.1.0"
      }
    },
    "NetworkSettings": {
      "IPAddress": "172.17.0.2",
      "Ports": {
        "8080/tcp": [{ "HostIp": "0.0.0.0", "HostPort": "3000" }]
      },
      "Networks": {
        "bridge": {
          "IPAddress": "172.17.0.2",
          "Gateway": "172.17.0.1"
        }
      }
    },
    "Mounts": [
      {
        "Type": "volume",
        "Name": "api-data",
        "Source": "/var/lib/docker/volumes/api-data/_data",
        "Destination": "/app/data",
        "RW": true
      }
    ],
    "HostConfig": {
      "RestartPolicy": { "Name": "unless-stopped", "MaximumRetryCount": 0 },
      "PortBindings": {
        "8080/tcp": [{ "HostIp": "", "HostPort": "3000" }]
      }
    }
  },
  "status": "success",
  "resource": "container",
  "operation": "inspect"
}

Expression Reference

Node Policies & GuardRails

Examples

Example 1: Failure diagnosis workflow

After a health-check workflow detects a container is not responding, use inspect to extract the exit code and error for incident reporting.

{
  "resource": "container",
  "operation": "inspect",
  "ContainerId": "{{ $trigger.containerName }}"
}
// Then in a Function node:
const exitCode = $input.container.State.ExitCode;
const finishedAt = $input.container.State.FinishedAt;
const errorMsg = $input.container.State.Error;
return {
  incidentSummary: `Container exited with code ${exitCode} at ${finishedAt}. Error: ${errorMsg || 'none'}`
};

Example 2: IP address discovery for network automation

Retrieve the container's IP and pass it to a Cloudflare or load-balancer node to update routing rules.

// Expression in downstream Cloudflare node:
// "value": "{{ $output.container.NetworkSettings.IPAddress }}"

Example 3: Config drift detection

Compare the running container's image tag against the expected version stored in a workflow variable and escalate if they differ.

// If Condition node:
// Left:  {{ $output.container.Config.Image }}
// Op:    not equals
// Right: {{ $vars.expectedImage }}
// → true branch: trigger alert and rollback workflow