This is one step in fixing issue adrienverge#88

It implements the /sources endpoint for a customer

localstripe/resources.py

@@ -678,6 +678,14 @@ def _api_delete(cls, id):
         schedule_webhook(Event('customer.deleted', obj))
         return super()._api_delete(id)
 
+    @classmethod
+    def _api_retrieve_sources(cls, id):
+        # return 404 if does not exist
+        Customer._api_retrieve(id)
+
+        obj = cls._api_retrieve(id)
+        return obj.sources
+
     @classmethod
     def _api_retrieve_source(cls, id, source_id, **kwargs):
         if kwargs:
@@ -818,6 +826,9 @@ def _api_update_subscription(cls, id, subscription_id, **data):
 
 
 extra_apis.extend((
+    # Retrieve list of sources:
+    ('GET', '/v1/customers/{id}/sources', Customer._api_retrieve_sources),
+    # Add a source
     ('POST', '/v1/customers/{id}/sources', Customer._api_add_source),
     # Retrieve single source by id:
     ('GET', '/v1/customers/{id}/sources/{source_id}',

test.sh

@@ -197,6 +197,12 @@ res=$(
   | grep -oE $card)
 [ -n "$res" ]
 
+# observe new card in customer sources response
+res=$(
+  curl -sSf -u $SK: $HOST/v1/customers/$cus/sources \
+  | grep -oE $card)
+[ -n "$res" ]
+
 # delete the card
 curl -sSf -u $SK: $HOST/v1/customers/$cus/sources/$card \
      -X DELETE