Cashback Claim

How to notify Fruga when a user completes a purchase to trigger a cashback reward.

POST https://api.fruga.com/cashback/claim

Property	Value
Authentication	HMAC-SHA256 request signing (see below)
Content type	`application/json`
Idempotency	Via `partnerEventId` — safe to retry
Caller	Partner backend only — not the browser or widget

Request headers

Header	Required	Description
`Content-Type`	Yes	Must be `application/json`
`X-Partner-Key`	Yes	Your partner environment key — `pk_test_...` for sandbox, `pk_live_...` for production
`X-Partner-Timestamp`	Yes	Current Unix timestamp in seconds. Requests with a timestamp more than 300 seconds from Fruga’s server time are rejected.
`X-Partner-Signature`	Yes	Base64-encoded HMAC-SHA256 signature of the canonical request string. See Signing the request below.

Request body

All fields are at the top level of a JSON object.

{
  "partnerEventId": "evt_9f8a3bd2-41c0-4f2e-9bda-abc123",
  "userRef": "user_123",
  "amount": 18.00,
  "redemptionContext": "NEW_POLICY"
}

{
  "partnerEventId": "evt_9f8a3bd2-41c0-4f2e-9bda-abc123",
  "userRef": "user_123",
  "amount": 18.00,
  "redemptionContext": "OTHER",
  "redemptionContextNotes": "Renewal loyalty bonus",
  "reference": {
    "policyId": 4451
  }
}

Fields

Field	Type	Required	Description
`partnerEventId`	string	Yes	A unique identifier you generate for this event. Fruga uses this for idempotency — submitting the same value again returns the original response without creating a duplicate. Must be unique per partner. We recommend using a UUID or a stable reference from your own system such as a transaction ID.
`userRef`	string	Yes	Your identifier for the user receiving the cashback. Must exactly match the `userRef` claim you use in the JWT assertion when that user opens the widget — this is how Fruga links the claim to the right wallet. Case-sensitive.
`amount`	number	Yes	The cashback amount in GBP, as a positive decimal. For example, `18.00` represents £18.00. Must be greater than zero.
`redemptionContext`	enum	Yes	The nature of the qualifying event. One of: `NEW_POLICY` · `POLICY_ADDON` · `CLAIM_EXCESS` · `OTHER`. When `OTHER` is used, `redemptionContextNotes` is required.
`redemptionContextNotes`	string	Conditional	A short description of the event. Required when `redemptionContext` is `OTHER`. Ignored for all other context values. Max 255 characters.
`reference`	object	No	Optional object for your own reconciliation data. Fruga stores this but does not act on it. Currently supports `policyId` (integer). Additional fields may be supported in future.

Signing the request

Every request must carry a valid HMAC-SHA256 signature. The signature proves the request came from your backend and has not been tampered with in transit. Requests with missing, invalid, or expired signatures are rejected with 401.

How to construct the signature

Record the current Unix timestamp

Get the current time as a Unix timestamp in seconds. This becomes the value of your X-Partner-Timestamp header. Fruga rejects requests where the timestamp is more than 300 seconds from its own clock — ensure your server is NTP-synced.

Hash the raw request body

Compute a SHA-256 hash of the raw JSON body string and encode it as lowercase hex. Do not pretty-print or reformat the JSON between hashing and sending — the body must be byte-for-byte identical.

Build the signing string

Concatenate the four components with dots: {timestamp}.POST./cashback/claim.{bodyHash}

Sign and encode

Compute HMAC-SHA256 of the signing string using your Signing Secret as the key. Base64-encode the result. This is your X-Partner-Signature header value.

Signing example

import crypto from 'crypto';

const buildSignedHeaders = (body) => {
  const timestamp = Math.floor(Date.now() / 1000).toString();
  const secret    = process.env.FRUGA_SIGNING_SECRET;
  const path      = '/cashback/claim';

  const bodyHash = crypto
    .createHash('sha256')
    .update(body)
    .digest('hex');

  const signingString = `${timestamp}.POST.${path}.${bodyHash}`;

  const signature = crypto
    .createHmac('sha256', secret)
    .update(signingString)
    .digest('base64');

  return {
    'Content-Type':        'application/json',
    'X-Partner-Key':       process.env.FRUGA_PARTNER_KEY,
    'X-Partner-Timestamp': timestamp,
    'X-Partner-Signature': signature,
  };
};

// Usage
const body = JSON.stringify({
  partnerEventId:    'evt_9f8a3bd2-41c0-4f2e-9bda-abc123',
  userRef:           'user_123',
  amount:            18.00,
  redemptionContext: 'NEW_POLICY',
  reference:         { policyId: 4451 },
});

const response = await fetch('https://api.fruga.com/cashback/claim', {
  method:  'POST',
  headers: buildSignedHeaders(body),
  body,
});

import hashlib, hmac, base64, time, json, os
import requests

def build_signed_headers(body: str) -> dict:
    timestamp = str(int(time.time()))
    secret    = os.environ["FRUGA_SIGNING_SECRET"].encode()
    path      = "/cashback/claim"

    body_hash = hashlib.sha256(body.encode()).hexdigest()
    signing_string = f"{timestamp}.POST.{path}.{body_hash}"
    signature = base64.b64encode(
        hmac.new(secret, signing_string.encode(), hashlib.sha256).digest()
    ).decode()

    return {
        "Content-Type":        "application/json",
        "X-Partner-Key":       os.environ["FRUGA_PARTNER_KEY"],
        "X-Partner-Timestamp": timestamp,
        "X-Partner-Signature": signature,
    }

# Usage
payload = json.dumps({
    "partnerEventId":    "evt_9f8a3bd2-41c0-4f2e-9bda-abc123",
    "userRef":           "user_123",
    "amount":            18.00,
    "redemptionContext": "NEW_POLICY",
    "reference":         { "policyId": 4451 },
}, separators=(",", ":"))  # compact — no extra whitespace

response = requests.post(
    "https://api.fruga.com/cashback/claim",
    headers=build_signed_headers(payload),
    data=payload,
)

⚠️

The JSON body must be serialised consistently. Fruga hashes the exact bytes it receives, so any difference in whitespace or key ordering between your hash and the sent body will cause a signature mismatch. Use compact serialisation (no extra spaces) and do not re-encode after hashing.

Responses

Success

Status	When	Body
`201 Created`	Claim recorded for the first time	No body
`200 OK`	Idempotent replay — `partnerEventId` already exists with the same body	No body

Errors

Status	Code	Meaning
`401`	`INVALID_SIGNATURE`	The `X-Partner-Signature` could not be verified. Check your signing string construction and that you are using the correct Signing Secret for this environment.
`401`	`TIMESTAMP_EXPIRED`	The `X-Partner-Timestamp` is more than 300 seconds from Fruga’s server time. Ensure your server clock is NTP-synced and that you are generating a fresh timestamp per request.
`401`	`UNKNOWN_PARTNER`	The `X-Partner-Key` does not match any active partner environment. Confirm you are using the correct key for sandbox or production.
`409 Conflict`	`IDEMPOTENCY_CONFLICT`	The `partnerEventId` has already been used, but the request body differs from the original. You cannot modify an existing claim. Contact Fruga support if a correction is needed.
`422`	`VALIDATION_ERROR`	One or more fields failed validation — for example, a negative `amount`, an invalid `redemptionContext` value, or a missing `redemptionContextNotes` when context is `OTHER`. The response body includes a `details` array describing each failure.

Error response body

{
  "error": "VALIDATION_ERROR",
  "message": "Request validation failed",
  "details": [
    {
      "field": "redemptionContextNotes",
      "message": "Required when redemptionContext is OTHER"
    }
  ]
}

Constraints and validation rules

Field	Rule
`partnerEventId`	Must be unique per partner. Max 128 characters. We recommend UUID v4 or a stable ID from your system.
`userRef`	Case-sensitive. Max 255 characters. Must match the `userRef` in the widget JWT assertion exactly.
`amount`	Must be a positive number greater than zero. Decimal values are accepted. Currency is always GBP.
`redemptionContext`	Must be one of the four accepted enum values. Unknown values return `422`.
`redemptionContextNotes`	Required if and only if `redemptionContext` is `OTHER`. Max 255 characters. Ignored for other context values.
`Timestamp tolerance`	The `X-Partner-Timestamp` must be within ±300 seconds of Fruga’s server time.

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Cashback Claim Guide