OCPP bridge

The OCPP bridge lets an Omega device act as an OCPP charge point: it opens an OCPP-J WebSocket to a Charge Point Management System (CPMS) and speaks the protocol — BootNotification, Heartbeat, StartTransaction / StopTransaction, MeterValues, ChangeConfiguration, and the rest — bridging that session to handlers on the device. It is native to Omega (not a deprecated module), but it is opt-in: you compile it in only for devices that need it.

1. Build with the feature

cargo build --release -p omega-agent --no-default-features --features ocpp

ocpp pulls a tokio runtime and a ZeroMQ transport (the bridge talks to its session handler over ZeroMQ). See Build Omega for the feature model.

2. Enable the module

Add the module to the profile and grant its capability. The module id is ocpp-bridge:

modules:
  required:
    - ocpp-bridge

security:
  capabilities:
    ocpp-bridge: true

3. Configure the bridge

The bridge reads an ocpp_bridge: section (note the underscore). The minimum is where to connect and how to identify the charge point:

ocpp_bridge:
  enabled: true
  cpms_url: wss://cpms.example.com/ocpp/CP-0001   # the CPMS WebSocket endpoint
  charge_point_id: CP-0001                        # sent as the WebSocket sub-protocol client id
  charge_point_vendor: Acme
  charge_point_model: DC-Fast-01
  firmware_version: 1.4.2
  heartbeat_interval_secs: 30

Config reference — `ocpp_bridge`

Field	Type	Default	Meaning
`enabled`	bool	`false`	Turn the bridge on.
`cpms_url`	string	—	Full WebSocket URL of the CPMS, e.g. `wss://host/ocpp/CP-0001`. Use `wss://` in production.
`charge_point_id`	string	`CP-0001`	Charge-point identity, sent as the WebSocket sub-protocol client id.
`charge_point_vendor`	string	`Golain`	Vendor reported in `BootNotification`.
`charge_point_model`	string	`Simulator`	Model reported in `BootNotification`.
`firmware_version`	string?	`0.1.0`	Firmware version reported in `BootNotification`.
`heartbeat_interval_secs`	u32	`10`	Initial heartbeat interval; the CPMS can override it via `BootNotificationResponse` / `ChangeConfiguration`.
`transaction_message_attempts`	u32	(built-in)	Retries for transaction messages (`StartTransaction`, `StopTransaction`, `MeterValues`) before giving up.
`transaction_message_retry_interval_secs`	u32	(built-in)	Delay between those retries.
`web_socket_ping_interval_secs`	u32	`0`	WebSocket Ping frame interval. `0` disables it.
`startup_sync_timeout_ms`	u64	(built-in)	Max wait for startup synchronization before opening the barrier with a warning.
`tls`	object?	none	Custom TLS for `wss://` (below).

TLS — `ocpp_bridge.tls`

For a CPMS that needs a custom CA or mutual TLS:

ocpp_bridge:
  tls:
    ca_cert_path: /etc/omega/cpms-ca.crt
    client_cert_path: /etc/omega/cp-client.crt
    client_key_path: /etc/omega/cp-client.key

Field	Meaning
`ca_cert_path`	CA to trust for the CPMS server certificate.
`client_cert_path` / `client_key_path`	Client certificate + key, for a CPMS that requires mTLS.

Omit tls to use the system trust store with no client certificate.

Internal transport (advanced)

The bridge communicates with its session handler over ZeroMQ. These default to loopback endpoints and rarely need changing:

Field	Meaning
`zmq_pub_endpoint`	Where the session handler subscribes for bridge → handler messages.
`zmq_sub_endpoint`	Where the session handler pushes requests toward the bridge.
`zmq_ctrl_rep_endpoint`	Control-plane endpoint the bridge exposes for readiness / synchronization.

Notes

This is a WebSocket-to-CPMS path, separate from Omega’s MQTT connection to the Golain platform — a device can run both: managed by Golain over MQTT, and speaking OCPP to a CPMS over its own WebSocket.
charge_point_id must match what the CPMS expects for this device; it’s part of the WebSocket URL and the sub-protocol handshake.

Omega edge runtime

Device RPC

Edge SQLite sync

Edge agent (Omega)

Operate & query

Wire protocol reference

1. Build with the feature

2. Enable the module

3. Configure the bridge

Config reference — `ocpp_bridge`

TLS — `ocpp_bridge.tls`

Internal transport (advanced)

Notes

See also

​1. Build with the feature

​2. Enable the module

​3. Configure the bridge

​Config reference — ocpp_bridge

​TLS — ocpp_bridge.tls

​Internal transport (advanced)

​Notes

​See also

1. Build with the feature

2. Enable the module

3. Configure the bridge

Config reference — `ocpp_bridge`

TLS — `ocpp_bridge.tls`

Internal transport (advanced)

Notes

See also