Subscription contract
Confirm pair identifiers, acknowledgements, quote fields and heartbeat behavior. WebSocket supplies a transport; the feed's JSON or binary message structure, authentication and recovery rules still need their own documentation.
Market data · deployment planning
Forex WebSocket API
Use WebSocket for FX quote delivery when clients need updates pushed over a persistent connection.
Reconnect sequence
Restore subscriptions after a network interruption and obtain an agreed starting state. Define how the client detects stale pairs, handles partial bid/ask messages and avoids displaying a recovered older quote over a newer one.
Requirements to confirm
- Pair and message catalogue
- Authentication and subscriptions
- Partial quote handling
- Reconnect and ordering rules
Bring the proposed instrument list, source documentation and consumer workflow to a technical discussion. The agreed integration specification defines coverage, fields, usage permissions and acceptance tests.
Integration brief
Forex WebSocket API: what to agree before connecting
| Subscription scope | Specify symbol identifiers, supported fields and acknowledgement or rejection behaviour. |
|---|---|
| Quote semantics | Agree snapshot versus incremental updates, source timestamps and status fields. |
| Consumer pressure | Define application buffer limits and what happens when a consumer cannot process updates fast enough. |
| Reconnect rules | Agree authentication, resubscription, fresh snapshot and duplicate-message handling. |
Recover application state explicitly
For Forex, define what a new subscriber receives before incremental updates begin. A connected socket does not prove a symbol is fresh. Separate heartbeat health from per-symbol timestamps and document the resubscription procedure after a disconnect.
What to test
- Disconnect during active updates and rebuild a current symbol state.
- Slow the consumer and observe the agreed buffering behaviour.
- Distinguish an inactive instrument from a stalled subscription.
{
"type": "quote",
"symbol": "EURUSD",
"bid": "1.10000",
"ask": "1.10010",
"source_time": "2026-10-18T12:00:00.000Z",
"received_at": "2026-10-18T12:00:00.012Z",
"source_id": "example-source",
"status": "illustrative"
}Illustrative engineering example, not live prices or a published API contract. Confirm field names and delivery rules during integration.