generated: '2026-07-22'
method: searched
source: |
  Euronext public client specifications (fetched 2026-07-22): Saturn 2.8.8
  spec PDF, EWS Indices v1.3 spec PDF, EWS Historical Data v1.0 spec PDF.
authentication:
  style: |
    EWS market data - authKey query parameter issued at onboarding, POST-only.
    Saturn - logon token in the Authorization header plus mutual TLS.
  artifact: authentication/euronext-authentication.yml
http_methods:
  note: |
    The Euronext Web Services API is POST-only - the specification states the
    GET method is not supported; request parameters ride the query string of
    the documented gateway URLs (gateway.euronext.com/api/instrumentDetail,
    /api/intraday). Saturn functions are POSTs to
    /SaturnWebServices/rest/<resource>/<action> paths (get, getTx, submit,
    submitTx, upload).
formats:
  ews: JSON only
  saturn: JSON, XML and CSV (FIX reserved for future use)
idempotency:
  supported: false
  note: No idempotency-key mechanism is documented for any Euronext API.
    Saturn deduplicates business-level trade submissions by trade reference
    within its check module, but there is no documented HTTP idempotency
    contract.
pagination:
  style: offset-limit
  parameters: [offset, limit]
  note: Saturn retrieval functions page with offset and limit query parameters
    (e.g. /SaturnWebServices/rest/transactionReports/getTx?offset=0&limit=1).
    EWS time-series requests are bounded by beginningDate/endingDate or period
    (1W..10Y) parameters instead of pagination.
field_expansion:
  supported: false
  note: EWS uses a fixed view=FULL parameter; no sparse fieldsets.
request_tracing:
  note: No request-id header convention is documented.
versioning:
  style: versioned PDF client specifications per API; no URL or header
    versioning.
  artifact: lifecycle/euronext-lifecycle.yml
error_envelope:
  shape: StatusCode + Message attributes on every Saturn response; EWS
    responses carry a status field ("0" = normal).
  artifact: errors/euronext-problem-types.yml
rate_limits:
  note: No rate-limit signaling (headers or documented quotas) appears in any
    public specification; access volume is governed contractually by the
    market data agreement / membership.
session_rules:
  note: |
    Saturn allows one active session per credential (a second logon
    invalidates the first), binds the session token to the logon client IP,
    expires tokens after a configurable idle period, and auto-logs-off idle
    clients.