Event Types

This page provides detailed information about each webhook event type, including payload structures and examples.

ocpp.message

The ocpp.message event is triggered whenever an OCPP message is sent to or received from a charging station. This provides real-time visibility into all communication between the Lynkwell platform and your charging infrastructure.

OCPP RPC Framework

OCPP (Open Charge Point Protocol) uses a JSON-RPC-like framework for communication between the central system (Lynkwell) and charging stations. Understanding the message types is essential for processing these webhooks correctly.

Message Types

Message Type	Description
`CALL`	A request message that initiates an action. Contains an `action` name and a `payload` with parameters.
`CALL_RESULT`	A successful response to a `CALL`. Contains only a `payload` with the result data.
`CALL_ERROR`	An error response to a `CALL`. Contains an `errorCode`, `errorDescription`, and optional `errorDetails`.

Message Correlation

Every OCPP message includes a messageId field. This ID is used to correlate requests with their responses:

A CALL message is sent with a unique messageId
The recipient responds with either a CALL_RESULT or CALL_ERROR using the same messageId

This allows you to match responses to their original requests when processing webhooks.

Station                          Lynkwell
   │                                │
   │  CALL (messageId: "abc123")    │
   │  Action: BootNotification      │
   │ ─────────────────────────────► │
   │                                │
   │  CALL_RESULT (messageId: "abc123")
   │ ◄───────────────────────────── │
   │                                │

Supported Protocols

The protocol field indicates which OCPP version the station is using:

ocpp1.6 - OCPP 1.6 (JSON)
ocpp2.0.1 - OCPP 2.0.1

Payload Structure

The data object in an ocpp.message webhook contains:

Field	Type	Description
`asset.id`	string	The unique identifier of the charging station
`connection.id`	string	The unique identifier for this connection session
`connection.protocol`	string	The OCPP protocol version (`ocpp1.6` or `ocpp2.0.1`)
`log`	object	The OCPP message details (varies by message type)
`timestamp`	string	ISO 8601 timestamp when the message was received

Examples

CALL - BootNotification (Station to Lynkwell)

When a charging station connects to the network, it sends a BootNotification to register itself:

{
  "id": "whevt_01JGXYZ123ABC456DEF789",
  "type": "ocpp.message",
  "createdAt": "2024-01-15T10:30:00.000Z",
  "data": {
    "asset": {
      "id": "ast_01ABC123XYZ"
    },
    "connection": {
      "id": "conn_01DEF456UVW",
      "protocol": "ocpp1.6"
    },
    "log": {
      "messageType": "CALL",
      "messageId": "1705315800000",
      "action": "BootNotification",
      "payload": "{\"chargePointVendor\":\"ExampleVendor\",\"chargePointModel\":\"Model X\",\"chargePointSerialNumber\":\"SN123456\",\"firmwareVersion\":\"1.0.0\"}"
    },
    "timestamp": "2024-01-15T10:30:00.000Z"
  }
}

CALL_RESULT - BootNotification Response (Lynkwell to Station)

The response to a successful BootNotification:

{
  "id": "whevt_01JGXYZ123ABC456DEF790",
  "type": "ocpp.message",
  "createdAt": "2024-01-15T10:30:00.100Z",
  "data": {
    "asset": {
      "id": "ast_01ABC123XYZ"
    },
    "connection": {
      "id": "conn_01DEF456UVW",
      "protocol": "ocpp1.6"
    },
    "log": {
      "messageType": "CALL_RESULT",
      "messageId": "1705315800000",
      "payload": "{\"status\":\"Accepted\",\"currentTime\":\"2024-01-15T10:30:00.100Z\",\"interval\":300}"
    },
    "timestamp": "2024-01-15T10:30:00.100Z"
  }
}

CALL - Heartbeat (Station to Lynkwell)

Stations send periodic Heartbeat messages to indicate they are still connected. The interval is determined by the interval field in the BootNotification response (e.g., every 300 seconds):

{
  "id": "whevt_01JGXYZ123ABC456DEF7A0",
  "type": "ocpp.message",
  "createdAt": "2024-01-15T10:35:00.000Z",
  "data": {
    "asset": {
      "id": "ast_01ABC123XYZ"
    },
    "connection": {
      "id": "conn_01DEF456UVW",
      "protocol": "ocpp1.6"
    },
    "log": {
      "messageType": "CALL",
      "messageId": "1705316100000",
      "action": "Heartbeat",
      "payload": "{}"
    },
    "timestamp": "2024-01-15T10:35:00.000Z"
  }
}

CALL_RESULT - Heartbeat Response (Lynkwell to Station)

The response contains the current server time, which stations use to synchronize their clocks:

{
  "id": "whevt_01JGXYZ123ABC456DEF7A1",
  "type": "ocpp.message",
  "createdAt": "2024-01-15T10:35:00.050Z",
  "data": {
    "asset": {
      "id": "ast_01ABC123XYZ"
    },
    "connection": {
      "id": "conn_01DEF456UVW",
      "protocol": "ocpp1.6"
    },
    "log": {
      "messageType": "CALL_RESULT",
      "messageId": "1705316100000",
      "payload": "{\"currentTime\":\"2024-01-15T10:35:00.050Z\"}"
    },
    "timestamp": "2024-01-15T10:35:00.050Z"
  }
}

CALL - StartTransaction (Station to Lynkwell)

When a charging session begins:

{
  "id": "whevt_01JGXYZ123ABC456DEF791",
  "type": "ocpp.message",
  "createdAt": "2024-01-15T11:00:00.000Z",
  "data": {
    "asset": {
      "id": "ast_01ABC123XYZ"
    },
    "connection": {
      "id": "conn_01DEF456UVW",
      "protocol": "ocpp1.6"
    },
    "log": {
      "messageType": "CALL",
      "messageId": "1705317600000",
      "action": "StartTransaction",
      "payload": "{\"connectorId\":1,\"idTag\":\"RFID123456\",\"meterStart\":0,\"timestamp\":\"2024-01-15T11:00:00.000Z\"}"
    },
    "timestamp": "2024-01-15T11:00:00.000Z"
  }
}

CALL - MeterValues (Station to Lynkwell)

Periodic energy consumption updates during charging:

{
  "id": "whevt_01JGXYZ123ABC456DEF792",
  "type": "ocpp.message",
  "createdAt": "2024-01-15T11:15:00.000Z",
  "data": {
    "asset": {
      "id": "ast_01ABC123XYZ"
    },
    "connection": {
      "id": "conn_01DEF456UVW",
      "protocol": "ocpp1.6"
    },
    "log": {
      "messageType": "CALL",
      "messageId": "1705318500000",
      "action": "MeterValues",
      "payload": "{\"connectorId\":1,\"transactionId\":12345,\"meterValue\":[{\"timestamp\":\"2024-01-15T11:15:00.000Z\",\"sampledValue\":[{\"value\":\"7500\",\"unit\":\"Wh\",\"measurand\":\"Energy.Active.Import.Register\"}]}]}"
    },
    "timestamp": "2024-01-15T11:15:00.000Z"
  }
}

CALL - StatusNotification (Station to Lynkwell)

Stations send StatusNotification messages whenever a connector's status changes. The payload contains a status field indicating the connector state and an errorCode field for fault detection.

Connector Statuses (OCPP 1.6):

Status	Description
`Available`	Connector is available for a new session
`Preparing`	Connector is preparing for a session (e.g., cable plugged in)
`Charging`	Connector is actively charging a vehicle
`SuspendedEV`	Charging suspended by the vehicle
`SuspendedEVSE`	Charging suspended by the charger
`Finishing`	Session is ending, connector will become available
`Reserved`	Connector is reserved for a specific user
`Unavailable`	Connector is not available (e.g., out of service)
`Faulted`	Connector has encountered an error

Detecting Faults:

To detect faults, check both the status and errorCode fields in the payload:

If status is Faulted, the connector has an active fault
The errorCode field provides details about the fault type (e.g., GroundFailure, OverCurrentFailure, PowerMeterFailure)
When errorCode is NoError, the connector is operating normally

Example - Normal Status Change (Charging):

{
  "id": "whevt_01JGXYZ123ABC456DEF793",
  "type": "ocpp.message",
  "createdAt": "2024-01-15T11:00:05.000Z",
  "data": {
    "asset": {
      "id": "ast_01ABC123XYZ"
    },
    "connection": {
      "id": "conn_01DEF456UVW",
      "protocol": "ocpp1.6"
    },
    "log": {
      "messageType": "CALL",
      "messageId": "1705317605000",
      "action": "StatusNotification",
      "payload": "{\"connectorId\":1,\"status\":\"Charging\",\"errorCode\":\"NoError\",\"timestamp\":\"2024-01-15T11:00:05.000Z\"}"
    },
    "timestamp": "2024-01-15T11:00:05.000Z"
  }
}

Example - Faulted Connector:

{
  "id": "whevt_01JGXYZ123ABC456DEF7B0",
  "type": "ocpp.message",
  "createdAt": "2024-01-15T14:22:30.000Z",
  "data": {
    "asset": {
      "id": "ast_01ABC123XYZ"
    },
    "connection": {
      "id": "conn_01DEF456UVW",
      "protocol": "ocpp1.6"
    },
    "log": {
      "messageType": "CALL",
      "messageId": "1705329750000",
      "action": "StatusNotification",
      "payload": "{\"connectorId\":1,\"status\":\"Faulted\",\"errorCode\":\"GroundFailure\",\"info\":\"Ground fault detected on connector\",\"timestamp\":\"2024-01-15T14:22:30.000Z\"}"
    },
    "timestamp": "2024-01-15T14:22:30.000Z"
  }
}

Error Codes (OCPP 1.6):

Error Code	Description
`NoError`	No error to report
`ConnectorLockFailure`	Failure to lock or unlock connector
`EVCommunicationError`	Communication failure with the vehicle
`GroundFailure`	Ground fault circuit interrupter activated
`HighTemperature`	Temperature inside Charge Point too high
`InternalError`	Error in internal hard- or software
`LocalListConflict`	Conflict with LocalAuthorizationList
`OtherError`	Other error (see `vendorErrorCode`)
`OverCurrentFailure`	Over current protection device tripped
`OverVoltage`	Voltage above acceptable level
`PowerMeterFailure`	Failure to read power meter
`PowerSwitchFailure`	Failure to control power switch
`ReaderFailure`	Failure with idTag reader
`ResetFailure`	Unable to perform a reset
`UnderVoltage`	Voltage below acceptable level
`WeakSignal`	Weak wireless signal

CALL - RemoteStartTransaction (Lynkwell to Station)

When you initiate a charging session remotely via the API:

{
  "id": "whevt_01JGXYZ123ABC456DEF794",
  "type": "ocpp.message",
  "createdAt": "2024-01-15T12:00:00.000Z",
  "data": {
    "asset": {
      "id": "ast_01ABC123XYZ"
    },
    "connection": {
      "id": "conn_01DEF456UVW",
      "protocol": "ocpp1.6"
    },
    "log": {
      "messageType": "CALL",
      "messageId": "lynk_1705321200000",
      "action": "RemoteStartTransaction",
      "payload": "{\"connectorId\":1,\"idTag\":\"REMOTE_START_TOKEN\"}"
    },
    "timestamp": "2024-01-15T12:00:00.000Z"
  }
}

CALL_RESULT - RemoteStartTransaction Response

{
  "id": "whevt_01JGXYZ123ABC456DEF795",
  "type": "ocpp.message",
  "createdAt": "2024-01-15T12:00:00.200Z",
  "data": {
    "asset": {
      "id": "ast_01ABC123XYZ"
    },
    "connection": {
      "id": "conn_01DEF456UVW",
      "protocol": "ocpp1.6"
    },
    "log": {
      "messageType": "CALL_RESULT",
      "messageId": "lynk_1705321200000",
      "payload": "{\"status\":\"Accepted\"}"
    },
    "timestamp": "2024-01-15T12:00:00.200Z"
  }
}

CALL_ERROR - Request Rejected

When a station cannot process a request:

{
  "id": "whevt_01JGXYZ123ABC456DEF796",
  "type": "ocpp.message",
  "createdAt": "2024-01-15T12:05:00.000Z",
  "data": {
    "asset": {
      "id": "ast_01ABC123XYZ"
    },
    "connection": {
      "id": "conn_01DEF456UVW",
      "protocol": "ocpp1.6"
    },
    "log": {
      "messageType": "CALL_ERROR",
      "messageId": "lynk_1705321500000",
      "errorCode": "NotSupported",
      "errorDescription": "Requested action is not supported by this charge point",
      "errorDetails": "{}"
    },
    "timestamp": "2024-01-15T12:05:00.000Z"
  }
}

Common Error Codes

When processing CALL_ERROR messages, you may encounter these error codes:

Error Code	Description
`NotImplemented`	The requested action is not implemented
`NotSupported`	The requested action is not supported
`InternalError`	An internal error occurred
`ProtocolError`	A protocol error occurred
`SecurityError`	A security error occurred
`FormationViolation`	The payload is malformed
`PropertyConstraintViolation`	A property constraint was violated
`OccurenceConstraintViolation`	An occurrence constraint was violated
`TypeConstraintViolation`	A type constraint was violated
`GenericError`	A generic error occurred

asset.connectivity

The asset.connectivity event is triggered when a charging station's connection status changes. This allows you to monitor the online/offline status of your charging infrastructure in real-time.

Connectivity Statuses

The connectivityStatus field indicates what happened:

Status	Description
`CONNECTED`	The station has established a WebSocket connection to the OCPP server
`DISCONNECTED`	The station has disconnected from the OCPP server

Connection Lifecycle

Station                          Lynkwell
   │                                │
   │  WebSocket Connect             │
   │ ─────────────────────────────► │
   │                                │  ← CONNECTED event
   │                                │
   │         ... normal operation ...
   │                                │
   │  WebSocket Disconnect          │
   │ ────────────────────────────X  │
   │                                │  ← DISCONNECTED event

Payload Structure

The data object in an asset.connectivity webhook contains:

Field	Type	Description
`assetId`	string	The unique identifier of the charging station
`timestamp`	string	ISO 8601 timestamp when the event occurred
`ocppServerVersion`	string	The OCPP server version handling this connection (`V1` or `V2`)
`connectivityStatus`	string	The connectivity event type: `CONNECTED` or `DISCONNECTED`

Examples

Station Connected

When a station first establishes a connection:

{
  "id": "whevt_01JGXYZ123ABC456DEF800",
  "type": "asset.connectivity",
  "createdAt": "2024-01-15T10:29:58.000Z",
  "data": {
    "assetId": "ast_01ABC123XYZ",
    "timestamp": "2024-01-15T10:29:58.000Z",
    "ocppServerVersion": "V1",
    "connectivityStatus": "CONNECTED"
  }
}

Station Disconnected

When a station loses connection:

{
  "id": "whevt_01JGXYZ123ABC456DEF802",
  "type": "asset.connectivity",
  "createdAt": "2024-01-15T18:45:30.000Z",
  "data": {
    "assetId": "ast_01ABC123XYZ",
    "timestamp": "2024-01-15T18:45:30.000Z",
    "ocppServerVersion": "V1",
    "connectivityStatus": "DISCONNECTED"
  }
}

Use Cases

Common use cases for asset.connectivity events:

Monitoring dashboards - Display real-time station status
Alerting - Notify operators when stations go offline
Analytics - Track station uptime and reliability metrics
Automated diagnostics - Trigger health checks when stations reconnect