generated: '2026-06-20'
method: searched
source: https://developers.ecommpay.com/en/en_gate_quickstart.html
docs:
  gate_interaction: https://developers.ecommpay.com/en/en_gate_interaction_organisation.html
  callbacks: https://developers.ecommpay.com/en/en_platform_callbacks.html
  codes: https://developers.ecommpay.com/en/en_platform_payment_info_codes.html
note: >-
  Cross-cutting request/response semantics for the ECOMMPAY Gate and Payment Page
  APIs, captured from the developer docs (no downloadable OpenAPI exists to derive
  from). Cross-links: authentication/ecommpay-authentication.yml,
  errors/ecommpay-decline-codes.yml, asyncapi/ecommpay-callbacks-webhooks.yml.
authentication:
  style: per-request HMAC-SHA-512 signature over parameters + numeric project_id
  detail: authentication/ecommpay-authentication.yml
interaction_model:
  synchronous: response returned inline (with signature) for some request types
  asynchronous: final result delivered via signed callback to the merchant web service
idempotency:
  supported: true
  mechanism: merchant-assigned natural key (payment_id)
  key_field: payment_id
  rule: >-
    The merchant supplies payment_id on every payment request; it can be any value but
    MUST be unique within the project. Reusing a payment_id that already exists in the
    project raises an error instead of creating a duplicate payment - i.e. the unique
    payment_id acts as a client-generated idempotency key that prevents double-charging.
  scope: per project_id
  note: >-
    There is no separate Idempotency-Key header; uniqueness is enforced on the
    merchant-controlled payment_id. request_id is a separate per-request correlation id
    returned on callbacks for tracing (not the idempotency key).
tracing:
  request_id: returned on callbacks/responses for correlating an operation to its request
metadata:
  supported: true
  note: Merchant reference/additional data can be passed and echoed back on callbacks.
error_envelope:
  status_field: operation.status
  code_field: operation.code
  message_field: operation.message
  format: unified numeric code + message (see errors/ecommpay-decline-codes.yml)
  problem_json: false
versioning:
  scheme: uri-path
  gate: /v2
  data_api: /v1
transport:
  tls: TLS 1.2+
  protocol: HTTP/1.1+