fix: add GraphQL cache invalidation for programs and modules

backend/apps/common/extensions.py

@@ -32,24 +32,23 @@ def get_protected_fields(schema: Schema) -> tuple[str, ...]:
     )
 
 
-class CacheExtension(SchemaExtension):
-    """CacheExtension class."""
+def generate_key(field_name: str, field_args: dict) -> str:
+    """Generate a unique cache key for a query.
 
-    def generate_key(self, field_name: str, field_args: dict) -> str:
-        """Generate a unique cache key for a query.
+    Args:
+        field_name (str): The GraphQL field name.
+        field_args (dict): The field's arguments.
 
-        Args:
-            field_name (str): The GraphQL field name.
-            field_args (dict): The field's arguments.
+    Returns:
+        str: The unique cache key.
 
-        Returns:
-            str: The unique cache key.
+    """
+    key = f"{field_name}:{json.dumps(field_args, sort_keys=True)}"
+    return f"{settings.GRAPHQL_RESOLVER_CACHE_PREFIX}-{hashlib.sha256(key.encode()).hexdigest()}"
 
-        """
-        key = f"{field_name}:{json.dumps(field_args, sort_keys=True)}"
-        return (
-            f"{settings.GRAPHQL_RESOLVER_CACHE_PREFIX}-{hashlib.sha256(key.encode()).hexdigest()}"
-        )
+
+class CacheExtension(SchemaExtension):
+    """CacheExtension class."""
 
     def resolve(self, _next, root, info, *args, **kwargs):
         """Wrap the resolver to provide caching."""
@@ -61,7 +60,45 @@ def resolve(self, _next, root, info, *args, **kwargs):
             return _next(root, info, *args, **kwargs)
 
         return cache.get_or_set(
-            self.generate_key(info.field_name, kwargs),
+            generate_key(info.field_name, kwargs),
             lambda: _next(root, info, *args, **kwargs),
             settings.GRAPHQL_RESOLVER_CACHE_TIME_SECONDS,
         )
+
+
+def invalidate_cache(field_name: str, field_args: dict) -> bool:
+    """Invalidate a specific GraphQL query from the resolver cache.
+
+    Args:
+        field_name: The GraphQL field name (e.g., 'getProgram').
+        field_args: The field's arguments as a dict (e.g., {'programKey': 'my-program'}).
+
+    Returns:
+        True if cache was invalidated, False if key didn't exist.
+
+    """
+    cache_key = generate_key(field_name, field_args)
+    return cache.delete(cache_key)
+
+
+def invalidate_program_cache(program_key: str) -> None:
+    """Invalidate all GraphQL caches related to a program.
+
+    Args:
+        program_key: The program's key identifier.
+
+    """
+    invalidate_cache("getProgram", {"programKey": program_key})
+    invalidate_cache("getProgramModules", {"programKey": program_key})
+
+
+def invalidate_module_cache(module_key: str, program_key: str) -> None:
+    """Invalidate all GraphQL caches related to a module.
+
+    Args:
+        module_key: The module's key identifier.
+        program_key: The program's key identifier.
+
+    """
+    invalidate_cache("getModule", {"moduleKey": module_key, "programKey": program_key})
+    invalidate_program_cache(program_key)

backend/apps/mentorship/api/internal/mutations/module.py

@@ -8,6 +8,7 @@
 from django.db import transaction
 from django.utils import timezone
 
+from apps.common.extensions import invalidate_module_cache, invalidate_program_cache
 from apps.github.models import User as GithubUser
 from apps.mentorship.api.internal.nodes.module import (
     CreateModuleInput,
@@ -119,6 +120,8 @@ def create_module(self, info: strawberry.Info, input_data: CreateModuleInput) ->
         mentors_to_set.add(creator_as_mentor)
         module.mentors.set(list(mentors_to_set))
 
+        invalidate_program_cache(program.key)
+
         return module
 
     @strawberry.mutation(permission_classes=[IsAuthenticated])
@@ -330,8 +333,9 @@ def update_module(self, info: strawberry.Info, input_data: UpdateModuleInput) ->
             module = Module.objects.select_related("program").get(
                 key=input_data.key, program__key=input_data.program_key
             )
+            old_module_key = module.key
         except Module.DoesNotExist as e:
-            raise ObjectDoesNotExist(msg=MODULE_NOT_FOUND_MSG) from e
+            raise ObjectDoesNotExist(MODULE_NOT_FOUND_MSG) from e
 
         try:
             creator_as_mentor = Mentor.objects.get(nest_user=user)
@@ -400,4 +404,8 @@ def update_module(self, info: strawberry.Info, input_data: UpdateModuleInput) ->
 
         module.program.save(update_fields=["experience_levels"])
 
+        invalidate_module_cache(old_module_key, module.program.key)
+        if module.key != old_module_key:
+            invalidate_module_cache(module.key, module.program.key)
+
         return module

backend/apps/mentorship/api/internal/mutations/program.py

@@ -6,6 +6,7 @@
 from django.core.exceptions import ObjectDoesNotExist, PermissionDenied, ValidationError
 from django.db import transaction
 
+from apps.common.extensions import invalidate_program_cache
 from apps.mentorship.api.internal.mutations.module import resolve_mentors_from_logins
 from apps.mentorship.api.internal.nodes.enum import ProgramStatusEnum
 from apps.mentorship.api.internal.nodes.program import (
@@ -76,6 +77,7 @@ def update_program(self, info: strawberry.Info, input_data: UpdateProgramInput)
 
         try:
             program = Program.objects.get(key=input_data.key)
+            old_key = program.key
         except Program.DoesNotExist as err:
             msg = f"Program with key '{input_data.key}' not found."
             logger.warning(msg, exc_info=True)
@@ -133,6 +135,10 @@ def update_program(self, info: strawberry.Info, input_data: UpdateProgramInput)
             admins_to_set = resolve_mentors_from_logins(input_data.admin_logins)
             program.admins.set(admins_to_set)
 
+        invalidate_program_cache(old_key)
+        if program.key != old_key:
+            invalidate_program_cache(program.key)
+
         return program
 
     @strawberry.mutation(permission_classes=[IsAuthenticated])
@@ -161,6 +167,8 @@ def update_program_status(
         program.status = input_data.status.value
         program.save()
 
+        invalidate_program_cache(program.key)
+
         logger.info("Updated status of program '%s' to '%s'", program.key, program.status)
 
         return program

backend/tests/apps/common/extensions_test.py

@@ -5,44 +5,39 @@
 import pytest
 from strawberry.permission import PermissionExtension
 
-from apps.common.extensions import CacheExtension, get_protected_fields
+from apps.common.extensions import CacheExtension, generate_key, get_protected_fields
 
 
 class TestGenerateKey:
     """Test cases for the generate_key method."""
 
-    @pytest.fixture
-    def extension(self):
-        """Return a CacheExtension instance."""
-        return CacheExtension()
-
-    def test_creates_deterministic_hash(self, extension):
+    def test_creates_deterministic_hash(self):
         """Test that generate_key creates a deterministic hash key."""
-        key1 = extension.generate_key("chapter", {"key": "germany"})
-        key2 = extension.generate_key("chapter", {"key": "germany"})
+        key1 = generate_key("chapter", {"key": "germany"})
+        key2 = generate_key("chapter", {"key": "germany"})
 
         assert key1 == key2
         assert key1.startswith("graphql-")
         assert len(key1.split("-")[-1]) == 64  # SHA256 hex digest length
 
-    def test_differs_for_different_field_names(self, extension):
+    def test_differs_for_different_field_names(self):
         """Test that different field names produce different keys."""
-        key1 = extension.generate_key("chapter", {"key": "germany"})
-        key2 = extension.generate_key("project", {"key": "germany"})
+        key1 = generate_key("chapter", {"key": "germany"})
+        key2 = generate_key("project", {"key": "germany"})
 
         assert key1 != key2
 
-    def test_differs_for_different_args(self, extension):
+    def test_differs_for_different_args(self):
         """Test that different arguments produce different keys."""
-        key1 = extension.generate_key("chapter", {"key": "germany"})
-        key2 = extension.generate_key("chapter", {"key": "canada"})
+        key1 = generate_key("chapter", {"key": "germany"})
+        key2 = generate_key("chapter", {"key": "canada"})
 
         assert key1 != key2
 
-    def test_sorts_args_for_consistency(self, extension):
+    def test_sorts_args_for_consistency(self):
         """Test that argument order doesn't affect the key."""
-        key1 = extension.generate_key("chapter", {"a": "1", "b": "2"})
-        key2 = extension.generate_key("chapter", {"b": "2", "a": "1"})
+        key1 = generate_key("chapter", {"a": "1", "b": "2"})
+        key2 = generate_key("chapter", {"b": "2", "a": "1"})
 
         assert key1 == key2
 

frontend/__tests__/unit/pages/CreateProgram.test.tsx

@@ -160,19 +160,23 @@ describe('CreateProgramPage (comprehensive tests)', () => {
     fireEvent.submit(screen.getByText('Save').closest('form'))
 
     await waitFor(() => {
-      expect(mockCreateProgram).toHaveBeenCalledWith({
-        variables: {
-          input: {
-            name: 'Test Program',
-            description: 'A description',
-            menteesLimit: 0,
-            startedAt: '2025-01-01',
-            endedAt: '2025-12-31',
-            tags: ['tag1', 'tag2'],
-            domains: ['domain1', 'domain2'],
+      expect(mockCreateProgram).toHaveBeenCalledWith(
+        expect.objectContaining({
+          variables: {
+            input: {
+              name: 'Test Program',
+              description: 'A description',
+              menteesLimit: 0,
+              startedAt: '2025-01-01',
+              endedAt: '2025-12-31',
+              tags: ['tag1', 'tag2'],
+              domains: ['domain1', 'domain2'],
+            },
           },
-        },
-      })
+          awaitRefetchQueries: true,
+          refetchQueries: expect.any(Array),
+        })
+      )
 
       expect(mockRouterPush).toHaveBeenCalledWith('/my/mentorship')
     })

frontend/src/app/mentorship/programs/[programKey]/modules/[moduleKey]/page.tsx

@@ -23,6 +23,7 @@ const ModuleDetailsPage = () => {
       programKey,
       moduleKey,
     },
+    fetchPolicy: 'cache-and-network',
   })
 
   const programModule = data?.getModule
@@ -34,7 +35,7 @@ const ModuleDetailsPage = () => {
     }
   }, [error])
 
-  if (isLoading) return <LoadingSpinner />
+  if (isLoading && !data) return <LoadingSpinner />
 
   if (error) {
     return (

frontend/src/app/mentorship/programs/[programKey]/page.tsx

@@ -20,6 +20,7 @@ const ProgramDetailsPage = () => {
   } = useQuery(GetProgramAndModulesDocument, {
     variables: { programKey },
     skip: !programKey,
+    fetchPolicy: 'cache-and-network',
   })
 
   const program = data?.getProgram
@@ -29,9 +30,9 @@ const ProgramDetailsPage = () => {
     if (graphQLRequestError) {
       handleAppError(graphQLRequestError)
     }
-  }, [graphQLRequestError, programKey])
+  }, [graphQLRequestError])
 
-  if (isLoading) return <LoadingSpinner />
+  if (isLoading && !data) return <LoadingSpinner />
 
   if (graphQLRequestError) {
     return (

frontend/src/app/my/mentorship/programs/[programKey]/edit/page.tsx

@@ -9,7 +9,10 @@ import { useState, useEffect } from 'react'
 import { ErrorDisplay, handleAppError } from 'app/global-error'
 import { ProgramStatusEnum } from 'types/__generated__/graphql'
 import { UpdateProgramDocument } from 'types/__generated__/programsMutations.generated'
-import { GetProgramDetailsDocument } from 'types/__generated__/programsQueries.generated'
+import {
+  GetMyProgramsDocument,
+  GetProgramDetailsDocument,
+} from 'types/__generated__/programsQueries.generated'
 import type { ExtendedSession } from 'types/auth'
 import { formatDateForInput } from 'utils/dateFormatter'
 import { parseCommaSeparated } from 'utils/parser'
@@ -104,7 +107,11 @@ const EditProgramPage = () => {
         status: formData.status,
       }
 
-      const result = await updateProgram({ variables: { input } })
+      const result = await updateProgram({
+        variables: { input },
+        refetchQueries: [{ query: GetMyProgramsDocument }],
+        awaitRefetchQueries: true,
+      })
       const updatedProgramKey = result.data?.updateProgram?.key || programKey
 
       addToast({

frontend/src/app/my/mentorship/programs/[programKey]/modules/[moduleKey]/edit/page.tsx

@@ -9,6 +9,7 @@ import { ErrorDisplay, handleAppError } from 'app/global-error'
 import { ExperienceLevelEnum } from 'types/__generated__/graphql'
 import { UpdateModuleDocument } from 'types/__generated__/moduleMutations.generated'
 import { GetProgramAdminsAndModulesDocument } from 'types/__generated__/moduleQueries.generated'
+import { GetProgramAndModulesDocument } from 'types/__generated__/programsQueries.generated'
 import type { ExtendedSession } from 'types/auth'
 import type { ModuleFormData } from 'types/mentorship'
 import { formatDateForInput } from 'utils/dateFormatter'
@@ -111,7 +112,11 @@ const EditModulePage = () => {
         tags: parseCommaSeparated(formData.tags),
       }
 
-      const result = await updateModule({ variables: { input } })
+      const result = await updateModule({
+        variables: { input },
+        refetchQueries: [{ query: GetProgramAndModulesDocument, variables: { programKey } }],
+        awaitRefetchQueries: true,
+      })
       const updatedModuleKey = result.data?.updateModule?.key || moduleKey
 
       addToast({

frontend/src/app/my/mentorship/programs/[programKey]/modules/[moduleKey]/page.tsx

@@ -25,6 +25,7 @@ const ModuleDetailsPage = () => {
       programKey,
       moduleKey,
     },
+    fetchPolicy: 'cache-and-network',
   })
 
   useEffect(() => {
@@ -36,7 +37,7 @@ const ModuleDetailsPage = () => {
     }
   }, [data, error])
 
-  if (isLoading) return <LoadingSpinner />
+  if (isLoading && !data) return <LoadingSpinner />
 
   if (!module) {
     return (

frontend/src/app/my/mentorship/programs/[programKey]/modules/create/page.tsx

@@ -4,7 +4,7 @@ import { addToast } from '@heroui/toast'
 import { useRouter, useParams } from 'next/navigation'
 import { useSession } from 'next-auth/react'
 import React, { useEffect, useState } from 'react'
-import { ErrorDisplay, handleAppError } from 'app/global-error'
+import { ErrorDisplay } from 'app/global-error'
 import { ExperienceLevelEnum } from 'types/__generated__/graphql'
 import { CreateModuleDocument } from 'types/__generated__/moduleMutations.generated'
 import {
@@ -100,29 +100,8 @@ const CreateModulePage = () => {
 
       await createModule({
         variables: { input },
-        update: (cache, { data: mutationData }) => {
-          const created = mutationData?.createModule
-          if (!created) return
-          try {
-            const existing = cache.readQuery({
-              query: GetProgramAndModulesDocument,
-              variables: { programKey },
-            })
-            if (existing?.getProgram && existing?.getProgramModules) {
-              cache.writeQuery({
-                query: GetProgramAndModulesDocument,
-                variables: { programKey },
-                data: {
-                  getProgram: existing.getProgram,
-                  getProgramModules: [created, ...existing.getProgramModules],
-                },
-              })
-            }
-          } catch (_err) {
-            handleAppError(_err)
-            return
-          }
-        },
+        refetchQueries: [{ query: GetProgramAndModulesDocument, variables: { programKey } }],
+        awaitRefetchQueries: true,
       })
 
       addToast({