feat: create customer id from email if missing

lnbits/fiat/base.py

@@ -95,6 +95,14 @@ class FiatSubscriptionPaymentOptions(BaseModel):
         description="Unique ID that can be used to identify the subscription request."
         "If not provided, one will be generated.",
     )
+    customer_id: str | None = Field(
+        default=None,
+        description="The fiat provider customer ID to use for the subscription.",
+    )
+    customer_email: str | None = Field(
+        default=None,
+        description="The customer email to use for the subscription.",
+    )
     tag: str | None = Field(
         default=None,
         description="Payments created by the recurring subscription"

lnbits/fiat/revolut.py

@@ -1,8 +1,8 @@
 import asyncio
 import ipaddress
 import json
-from decimal import Decimal, ROUND_HALF_UP
 from collections.abc import AsyncGenerator
+from decimal import ROUND_HALF_UP, Decimal
 from typing import Any
 from urllib.parse import urlparse
 
@@ -212,13 +212,6 @@ class RevolutWallet(FiatProvider):
             )
 
         extra = payment_options.extra or {}
-        customer_id = extra.get("customer_id")
-        if not customer_id:
-            return FiatSubscriptionResponse(
-                ok=False,
-                error_message="Revolut subscriptions require extra.customer_id.",
-            )
-
         if not payment_options.subscription_request_id:
             payment_options.subscription_request_id = urlsafe_short_hash()
 
@@ -231,7 +224,6 @@ class RevolutWallet(FiatProvider):
         )
         payload: dict[str, Any] = {
             "plan_variation_id": subscription_id,
-            "customer_id": customer_id,
             "external_reference": self._serialize_subscription_reference(reference),
             "setup_order_redirect_url": (
                 payment_options.success_url
@@ -248,6 +240,12 @@ class RevolutWallet(FiatProvider):
         }
 
         try:
+            customer_id, customer_error = await self._get_subscription_customer_id(
+                payment_options
+            )
+            if not customer_id:
+                return FiatSubscriptionResponse(ok=False, error_message=customer_error)
+            payload["customer_id"] = customer_id
             r = await self.client.post(
                 "/api/subscriptions", json=payload, headers=headers
             )
@@ -351,6 +349,31 @@ class RevolutWallet(FiatProvider):
         r.raise_for_status()
         return r.json()
 
+    async def _get_subscription_customer_id(
+        self, payment_options: FiatSubscriptionPaymentOptions
+    ) -> tuple[str | None, str | None]:
+        if payment_options.customer_id:
+            return payment_options.customer_id, None
+        if not payment_options.customer_email:
+            payment_options.customer_email = "test@lnbits.com"
+            # TODO: Remove the above line and uncomment the
+            # below return statement once we require customer_email for subscriptions.
+            # return (
+            #     None,
+            #     "Revolut subscriptions require customer_id or customer_email.",
+            # )
+
+        customer = await self.create_customer(payment_options.customer_email)
+        customer_id = customer.get("id")
+        if not customer_id:
+            return None, "Server error: missing customer id"
+        return customer_id, None
+
+    async def create_customer(self, email: str) -> dict[str, Any]:
+        r = await self.client.post("/api/customers", json={"email": email})
+        r.raise_for_status()
+        return r.json()
+
     @classmethod
     async def create_webhook(
         cls,

tests/unit/test_fiat_providers.py

@@ -896,7 +896,8 @@ async def test_revolut_wallet_create_subscription(settings: Settings):
         wallet_id="wallet_1",
         memo="Monthly Gold",
         tag="gold",
-        extra={"customer_id": "CUSTOMER123", "link": "link-1"},
+        customer_id="CUSTOMER123",
+        extra={"link": "link-1"},
         success_url="https://lnbits.example/subscription-success",
     )
 
@@ -921,10 +922,77 @@ async def test_revolut_wallet_create_subscription(settings: Settings):
     assert reference["wallet_id"] == "wallet_1"
     assert reference["tag"] == "gold"
     assert reference["memo"] == "Monthly Gold"
-    assert reference["extra"]["customer_id"] == "CUSTOMER123"
+    assert reference["extra"]["link"] == "link-1"
     assert client.calls[1][0] == "/api/orders/ORDER123"
 
 
+@pytest.mark.anyio
+async def test_revolut_wallet_create_subscription_creates_customer(settings: Settings):
+    settings.revolut_api_endpoint = "https://sandbox-merchant.revolut.com"
+    settings.revolut_api_secret_key = "revolut-secret"
+    settings.revolut_api_version = "2026-04-20"
+
+    wallet = RevolutWallet()
+    client = MockHTTPClient(
+        [
+            MockHTTPResponse(json_data={"id": "CUSTOMER123"}),
+            MockHTTPResponse(
+                json_data={
+                    "id": "SUBSCRIPTION123",
+                    "setup_order_id": "ORDER123",
+                }
+            ),
+            MockHTTPResponse(
+                json_data={
+                    "id": "ORDER123",
+                    "checkout_url": "https://checkout.revolut.com/payment-link/sub_123",
+                }
+            ),
+        ]
+    )
+    wallet.client = client  # type: ignore[assignment]
+
+    payment_options = FiatSubscriptionPaymentOptions(
+        wallet_id="wallet_1",
+        customer_email="customer@example.com",
+    )
+
+    response = await wallet.create_subscription(
+        "PLAN_VARIATION_123", 1, payment_options
+    )
+
+    assert response.ok is True
+    assert client.calls[0][0] == "/api/customers"
+    assert client.calls[0][1]["json"] == {"email": "customer@example.com"}
+    assert client.calls[1][0] == "/api/subscriptions"
+    assert client.calls[1][1]["json"]["customer_id"] == "CUSTOMER123"
+    assert client.calls[2][0] == "/api/orders/ORDER123"
+
+
+@pytest.mark.anyio
+async def test_revolut_wallet_create_subscription_requires_customer(settings: Settings):
+    settings.revolut_api_endpoint = "https://sandbox-merchant.revolut.com"
+    settings.revolut_api_secret_key = "revolut-secret"
+    settings.revolut_api_version = "2026-04-20"
+
+    wallet = RevolutWallet()
+    client = MockHTTPClient([])
+    wallet.client = client  # type: ignore[assignment]
+
+    payment_options = FiatSubscriptionPaymentOptions(wallet_id="wallet_1")
+
+    response = await wallet.create_subscription(
+        "PLAN_VARIATION_123", 1, payment_options
+    )
+
+    assert response.ok is False
+    assert (
+        response.error_message
+        == "Revolut subscriptions require customer_id or customer_email."
+    )
+    assert client.calls == []
+
+
 @pytest.mark.anyio
 async def test_revolut_wallet_cancel_subscription(settings: Settings):
     settings.revolut_api_endpoint = "https://sandbox-merchant.revolut.com"