Stripe global settings (#521)

* Add fields to input stripe key global settings

* Update validator

* Hide sensitive data

src/pretix/control/forms/global_settings.py

@@ -1,4 +1,5 @@
 from collections import OrderedDict
+from typing import List, Union
 
 from django import forms
 from django.conf import settings
@@ -142,10 +143,53 @@ def __init__(self, *args, **kwargs):
         self.fields['banner_message'].widget.attrs['rows'] = '2'
         self.fields['banner_message_detail'].widget.attrs['rows'] = '3'
         self.fields = OrderedDict(list(self.fields.items()) + [
-            ('stripe_webhook_secret_key', SecretKeySettingsField(
-                label=_('Stripe Webhook: Signing secret'),
-                required=False,
-            )),
+            (
+                'payment_stripe_connect_secret_key',
+                SecretKeySettingsField(
+                    label=_('Stripe Connect: Secret key'),
+                    required=False,
+                    validators=(
+                        StripeKeyValidator(['sk_live_', 'rk_live_']),
+                    ),
+                )
+            ),
+            (
+                'payment_stripe_connect_publishable_key',
+                forms.CharField(
+                    label=_('Stripe Connect: Publishable key'),
+                    required=False,
+                    validators=(
+                        StripeKeyValidator('pk_live_'),
+                    ),
+                )
+            ),
+            (
+                'payment_stripe_connect_test_secret_key',
+                SecretKeySettingsField(
+                    label=_('Stripe Connect: Secret key (test)'),
+                    required=False,
+                    validators=(
+                        StripeKeyValidator(['sk_test_', 'rk_test_']),
+                    ),
+                )
+            ),
+            (
+                'payment_stripe_connect_test_publishable_key',
+                forms.CharField(
+                    label=_('Stripe Connect: Publishable key (test)'),
+                    required=False,
+                    validators=(
+                        StripeKeyValidator('pk_test_'),
+                    ),
+                )
+            ),
+            (
+                'stripe_webhook_secret_key',
+                SecretKeySettingsField(
+                    label=_('Stripe Webhook: Secret key'),
+                    required=False,
+                )
+            ),
             (
                 "ticket_fee_percentage",
                 forms.DecimalField(
@@ -195,3 +239,46 @@ class SSOConfigForm(SettingsForm):
     def __init__(self, *args, **kwargs):
         self.obj = GlobalSettingsObject()
         super().__init__(*args, obj=self.obj, **kwargs)
+
+
+class StripeKeyValidator:
+    """
+    Validates that a given Stripe key starts with the expected prefix(es).
+
+    This validator ensures that Stripe API keys conform to the expected format
+    by checking their prefixes. It supports both single prefix validation and
+    multiple prefix validation.
+    """
+    def __init__(self, prefix: Union[str, List[str]]) -> None:
+        if not prefix:
+            raise ValueError("Prefix cannot be empty")
+
+        if isinstance(prefix, list):
+            if not all(isinstance(p, str) and p for p in prefix):
+                raise ValueError("All prefixes must be non-empty strings")
+            self._prefixes = prefix
+        elif isinstance(prefix, str):
+            if not prefix.strip():
+                raise ValueError("Prefix cannot be whitespace")
+            self._prefixes = [prefix]
+
+    def __call__(self, value: str) -> None:
+        if not value:
+            raise forms.ValidationError(
+                _("The Stripe key cannot be empty."),
+                code='invalid-stripe-key'
+            )
+
+        if not any(value.startswith(p) for p in self._prefixes):
+            if len(self._prefixes) == 1:
+                message = _('The provided key does not look valid. It should start with "%(prefix)s".')
+                params = {'value': value, 'prefix': self._prefixes[0]}
+            else:
+                message = _('The provided key does not look valid. It should start with one of: %(prefixes)s')
+                params = {'value': value, 'prefixes': ', '.join(f'"{p}"' for p in self._prefixes)}
+
+            raise forms.ValidationError(
+                message,
+                code='invalid-stripe-key',
+                params=params
+            )