perf: cache calls for calculating utm_source

course_discovery/apps/api/cache.py

@@ -5,6 +5,7 @@
 from django.conf import settings
 from django.core.cache import cache
 from django.http.response import HttpResponse
+from edx_django_utils.cache import get_cache_key
 from rest_framework.renderers import JSONRenderer
 from rest_framework_extensions.cache.decorators import CacheResponse
 from rest_framework_extensions.key_constructor.bits import KeyBitBase, QueryParamsKeyBit
@@ -165,3 +166,6 @@ def list(self, request, *args, **kwargs):
     )
     def retrieve(self, request, *args, **kwargs):
         return super().retrieve(request, *args, **kwargs)
+
+def get_utm_source_request_cache_key(partner, user):
+    return get_cache_key(partner=partner.id, user=user.id)

course_discovery/apps/api/serializers.py

@@ -17,6 +17,7 @@
 from django.utils.text import slugify
 from django.utils.translation import gettext_lazy as _
 from django_countries.serializer_fields import CountryField
+from edx_django_utils.cache import RequestCache, get_cache_key
 from localflavor.us.us_states import CONTIGUOUS_STATES
 from opaque_keys.edx.locator import CourseLocator
 from rest_flex_fields.serializers import FlexFieldsSerializerMixin
@@ -28,10 +29,11 @@
 from taxonomy.choices import ProductTypes
 from taxonomy.utils import get_whitelisted_serialized_skills
 
+from course_discovery.apps.api.cache import get_utm_source_request_cache_key
 from course_discovery.apps.api.fields import (
     HtmlField, ImageField, SlugRelatedFieldWithReadSerializer, SlugRelatedTranslatableField, StdImageSerializerField
 )
-from course_discovery.apps.api.utils import StudioAPI, get_excluded_restriction_types
+from course_discovery.apps.api.utils import StudioAPI, get_excluded_restriction_types, use_request_cache
 from course_discovery.apps.catalogs.models import Catalog
 from course_discovery.apps.core.api_client.lms import LMSAPIClient
 from course_discovery.apps.core.utils import update_instance
@@ -146,7 +148,7 @@ def get_lms_course_url_for_archived(partner, course_key):
 
     return f'{lms_url}/courses/{course_key}/course/'
 
-
+@use_request_cache("utm_source_cache", get_utm_source_request_cache_key)
 def get_utm_source_for_user(partner, user):
     """
     Return the utm source for the user.

course_discovery/apps/api/utils.py

@@ -7,6 +7,7 @@
 from django.core.files.base import ContentFile
 from django.db.models.fields.related import ManyToManyField
 from django.utils.translation import gettext as _
+from edx_django_utils.cache import RequestCache, get_cache_key
 from opaque_keys.edx.keys import CourseKey
 from requests.exceptions import HTTPError
 from sortedm2m.fields import SortedManyToManyField
@@ -352,3 +353,20 @@ def push_to_studio(self, course_run, create=False, old_course_run_key=None, user
             self.create_course_run_in_studio(course_run, user=user)
         else:
             self.update_course_run_details_in_studio(course_run)
+
+def use_request_cache(cache_name, key_func):
+    def inner(fn):
+        @functools.wraps(fn)
+        def foo(*args, **kwargs):
+            cache = RequestCache(cache_name)
+            cache_key = key_func(*args, **kwargs)
+            cached_response = cache.get_cached_response(cache_key)
+            if cached_response.is_found:
+                return cached_response.value
+
+            ret_val = fn(*args, **kwargs)
+
+            cache.set(cache_key, ret_val)
+            return ret_val
+        return foo
+    return inner