Emit a cache miss + stale when field's age can't be computed (#350)

Author: BoD

normalized-cache/src/commonMain/kotlin/com/apollographql/cache/normalized/api/CacheResolver.kt

@@ -256,6 +256,15 @@ class CacheControlCacheResolver(
         }
         if (staleDuration >= 0) isStale = true
       }
+
+      if (receivedDate == null && expirationDate == null) {
+        // We can't determine the field's staleness: consider it stale
+        throw CacheMissException(
+            key = context.parentKey.keyToString(),
+            fieldName = context.getFieldKey(),
+            stale = true,
+        )
+      }
     }
 
     val value = delegateResolver.resolveField(context)

tests/cache-control/src/commonTest/kotlin/StaleTest.kt

@@ -22,6 +22,7 @@ import com.apollographql.cache.normalized.storeReceivedDate
 import com.apollographql.mockserver.MockResponse
 import com.apollographql.mockserver.MockServer
 import declarative.GetUserNameQuery
+import declarative.cache.Cache.cache
 import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.test.runTest
 import kotlin.test.Test
@@ -97,4 +98,34 @@ class StaleTest {
       awaitComplete()
     }
   }
+
+  @Test
+  fun unknownAgeConsideredStale() = runTest {
+    val apolloClient = ApolloClient.Builder()
+        .serverUrl("http://unused")
+        .cache(MemoryCacheFactory())
+        .build()
+
+    apolloClient.apolloStore.writeOperation(
+        operation = GetUserNameQuery(),
+        data = GetUserNameQuery.Data(
+            GetUserNameQuery.User(
+                __typename = "User",
+                name = "John Doe",
+            ),
+        ),
+    )
+    val response = apolloClient
+        .query(GetUserNameQuery())
+        .fetchPolicy(FetchPolicy.CacheOnly)
+        .execute()
+
+    // No stored received date, so age can't be computed -> considered stale
+    assertIs<ApolloResponse<GetUserNameQuery.Data>>(response)
+    assertEquals(true, response.cacheInfo?.isStale)
+    assertNull(response.data)
+    assertNotNull(response.exception)
+    assertIs<CacheMissException>(response.exception)
+    assertEquals(true, response.isFromCache)
+  }
 }

tests/partial-results/src/commonTest/kotlin/test/CachePartialResultTest.kt

@@ -944,8 +944,7 @@ class CachePartialResultTest {
   fun onErrorNullWithCatchToNull() = runTest(before = { setUp() }, after = { tearDown() }) {
     ApolloClient.Builder()
         .serverUrl(mockServer.url())
-        .normalizedCache(MemoryCacheFactory(), cacheKeyGenerator = TypePolicyCacheKeyGenerator(Cache.typePolicies), cacheResolver = CacheControlCacheResolver(SchemaCoordinatesMaxAgeProvider(Cache.maxAges, Duration.INFINITE), FieldPolicyCacheResolver(Cache.fieldPolicies)))
-        .storeReceivedDate(true)
+        .normalizedCache(MemoryCacheFactory(), cacheKeyGenerator = TypePolicyCacheKeyGenerator(Cache.typePolicies), cacheResolver = FieldPolicyCacheResolver(Cache.fieldPolicies))
         .build()
         .use { apolloClient ->
           val cacheMissResult = apolloClient.query(GetFooQuery())
@@ -1001,8 +1000,7 @@ class CachePartialResultTest {
   fun onErrorHalt() = runTest(before = { setUp() }, after = { tearDown() }) {
     ApolloClient.Builder()
         .serverUrl(mockServer.url())
-        .normalizedCache(MemoryCacheFactory(), cacheKeyGenerator = TypePolicyCacheKeyGenerator(Cache.typePolicies), cacheResolver = CacheControlCacheResolver(SchemaCoordinatesMaxAgeProvider(Cache.maxAges, Duration.INFINITE), FieldPolicyCacheResolver(Cache.fieldPolicies)))
-        .storeReceivedDate(true)
+        .normalizedCache(MemoryCacheFactory(), cacheKeyGenerator = TypePolicyCacheKeyGenerator(Cache.typePolicies), cacheResolver = FieldPolicyCacheResolver(Cache.fieldPolicies))
         .build()
         .use { apolloClient ->
           val cacheMissResult = apolloClient.query(GetFoo2Query())