LRU Gc for memory (#4724)

Author: wu-hui

firebase-firestore/api.txt

@@ -316,11 +316,34 @@ package com.google.firebase.firestore {
   }
 
   public final class MemoryCacheSettings implements com.google.firebase.firestore.LocalCacheSettings {
+    method @NonNull public com.google.firebase.firestore.MemoryGarbageCollectorSettings getGarbageCollectorSettings();
     method @NonNull public static com.google.firebase.firestore.MemoryCacheSettings.Builder newBuilder();
   }
 
   public static class MemoryCacheSettings.Builder {
     method @NonNull public com.google.firebase.firestore.MemoryCacheSettings build();
+    method @NonNull public com.google.firebase.firestore.MemoryCacheSettings.Builder setGcSettings(@NonNull com.google.firebase.firestore.MemoryGarbageCollectorSettings);
+  }
+
+  public final class MemoryEagerGcSettings implements com.google.firebase.firestore.MemoryGarbageCollectorSettings {
+    method @NonNull public static com.google.firebase.firestore.MemoryEagerGcSettings.Builder newBuilder();
+  }
+
+  public static class MemoryEagerGcSettings.Builder {
+    method @NonNull public com.google.firebase.firestore.MemoryEagerGcSettings build();
+  }
+
+  public interface MemoryGarbageCollectorSettings {
+  }
+
+  public final class MemoryLruGcSettings implements com.google.firebase.firestore.MemoryGarbageCollectorSettings {
+    method public long getSizeBytes();
+    method @NonNull public static com.google.firebase.firestore.MemoryLruGcSettings.Builder newBuilder();
+  }
+
+  public static class MemoryLruGcSettings.Builder {
+    method @NonNull public com.google.firebase.firestore.MemoryLruGcSettings build();
+    method public void setSizeBytes(long);
   }
 
   public enum MetadataChanges {

firebase-firestore/ktx/api.txt

@@ -12,6 +12,8 @@ package com.google.firebase.firestore.ktx {
     method public static inline <reified T> T getField(@NonNull com.google.firebase.firestore.DocumentSnapshot, @NonNull com.google.firebase.firestore.FieldPath fieldPath, @NonNull com.google.firebase.firestore.DocumentSnapshot.ServerTimestampBehavior serverTimestampBehavior);
     method @NonNull public static com.google.firebase.firestore.FirebaseFirestore getFirestore(@NonNull com.google.firebase.ktx.Firebase);
     method @NonNull public static com.google.firebase.firestore.MemoryCacheSettings memoryCacheSettings(@NonNull kotlin.jvm.functions.Function1<? super com.google.firebase.firestore.MemoryCacheSettings.Builder,kotlin.Unit> init);
+    method @NonNull public static com.google.firebase.firestore.MemoryEagerGcSettings memoryEagerGcSettings(@NonNull kotlin.jvm.functions.Function1<? super com.google.firebase.firestore.MemoryEagerGcSettings.Builder,kotlin.Unit> init);
+    method @NonNull public static com.google.firebase.firestore.MemoryLruGcSettings memoryLruGcSettings(@NonNull kotlin.jvm.functions.Function1<? super com.google.firebase.firestore.MemoryLruGcSettings.Builder,kotlin.Unit> init);
     method @NonNull public static com.google.firebase.firestore.PersistentCacheSettings persistentCacheSettings(@NonNull kotlin.jvm.functions.Function1<? super com.google.firebase.firestore.PersistentCacheSettings.Builder,kotlin.Unit> init);
     method @NonNull public static kotlinx.coroutines.flow.Flow<com.google.firebase.firestore.DocumentSnapshot> snapshots(@NonNull com.google.firebase.firestore.DocumentReference, @NonNull com.google.firebase.firestore.MetadataChanges metadataChanges = com.google.firebase.firestore.MetadataChanges.EXCLUDE);
     method @NonNull public static kotlinx.coroutines.flow.Flow<com.google.firebase.firestore.QuerySnapshot> snapshots(@NonNull com.google.firebase.firestore.Query, @NonNull com.google.firebase.firestore.MetadataChanges metadataChanges = com.google.firebase.firestore.MetadataChanges.EXCLUDE);

firebase-firestore/ktx/src/main/kotlin/com/google/firebase/firestore/ktx/Firestore.kt

@@ -182,6 +182,18 @@ fun memoryCacheSettings(init: MemoryCacheSettings.Builder.() -> Unit): MemoryCac
   return builder.build()
 }
 
+fun memoryEagerGcSettings(init: MemoryEagerGcSettings.Builder.() -> Unit): MemoryEagerGcSettings {
+  val builder = MemoryEagerGcSettings.newBuilder()
+  builder.init()
+  return builder.build()
+}
+
+fun memoryLruGcSettings(init: MemoryLruGcSettings.Builder.() -> Unit): MemoryLruGcSettings {
+  val builder = MemoryLruGcSettings.newBuilder()
+  builder.init()
+  return builder.build()
+}
+
 fun persistentCacheSettings(
   init: PersistentCacheSettings.Builder.() -> Unit
 ): PersistentCacheSettings {

firebase-firestore/ktx/src/test/kotlin/com/google/firebase/firestore/ktx/FirestoreTests.kt

@@ -124,6 +124,34 @@ class FirestoreTests : BaseTestCase() {
     assertThat(otherSettings.isSslEnabled).isEqualTo(true)
     assertThat(otherSettings.isPersistenceEnabled).isFalse()
   }
+
+  @Test
+  fun `MemoryCacheSettings Garbage Collector builder works`() {
+    val host = "http://10.0.2.2:8080"
+    val isSslEnabled = false
+
+    val settings = firestoreSettings {
+      this.host = host
+      this.isSslEnabled = isSslEnabled
+      this.setLocalCacheSettings(memoryCacheSettings {})
+    }
+
+    assertThat(host).isEqualTo(settings.host)
+    assertThat(isSslEnabled).isEqualTo(settings.isSslEnabled)
+    assertThat(settings.isPersistenceEnabled).isFalse()
+    assertThat(settings.cacheSettings)
+      .isEqualTo(memoryCacheSettings { setGcSettings(memoryEagerGcSettings {}) })
+
+    val otherSettings = firestoreSettings {
+      this.setLocalCacheSettings(
+        memoryCacheSettings { setGcSettings(memoryLruGcSettings { setSizeBytes(1_000) }) }
+      )
+    }
+
+    assertThat(otherSettings.host).isEqualTo(FirebaseFirestoreSettings.DEFAULT_HOST)
+    assertThat(otherSettings.isPersistenceEnabled).isFalse()
+    assertThat(otherSettings.cacheSizeBytes).isEqualTo(1_000)
+  }
 }
 
 @RunWith(RobolectricTestRunner::class)

firebase-firestore/src/androidTest/java/com/google/firebase/firestore/FirestoreTest.java

@@ -1298,4 +1298,43 @@ public void testNewCacheConfigForPersistentCache() {
     DocumentSnapshot snap = waitFor(instance.document("coll/doc").get(Source.CACHE));
     assertEquals(map("foo", "bar"), snap.getData());
   }
+
+  @Test
+  public void testCanGetDocumentWithMemoryLruGCEnabled() {
+    FirebaseFirestore db = testFirestore();
+    db.setFirestoreSettings(
+        new FirebaseFirestoreSettings.Builder(db.getFirestoreSettings())
+            .setLocalCacheSettings(
+                MemoryCacheSettings.newBuilder()
+                    .setGcSettings(MemoryLruGcSettings.newBuilder().build())
+                    .build())
+            .build());
+
+    DocumentReference doc = db.collection("abc").document("123");
+    waitFor(doc.set(map("key", "value")));
+
+    DocumentSnapshot snapshot = waitFor(doc.get(Source.CACHE));
+    assertTrue(snapshot.exists());
+    assertTrue(snapshot.getMetadata().isFromCache());
+    assertEquals(snapshot.getData(), map("key", "value"));
+  }
+
+  @Test
+  public void testCannotGetDocumentWithMemoryEagerGcEnabled() {
+    FirebaseFirestore db = testFirestore();
+    db.setFirestoreSettings(
+        new FirebaseFirestoreSettings.Builder(db.getFirestoreSettings())
+            .setLocalCacheSettings(
+                MemoryCacheSettings.newBuilder()
+                    .setGcSettings(MemoryEagerGcSettings.newBuilder().build())
+                    .build())
+            .build());
+
+    DocumentReference doc = db.collection("abc").document("123");
+    waitFor(doc.set(map("key", "value")));
+
+    Exception e = waitForException(doc.get(Source.CACHE));
+    assertTrue(e instanceof FirebaseFirestoreException);
+    assertEquals(((FirebaseFirestoreException) e).getCode(), Code.UNAVAILABLE);
+  }
 }

firebase-firestore/src/main/java/com/google/firebase/firestore/FirebaseFirestoreSettings.java

@@ -40,6 +40,7 @@ public static final class Builder {
     private String host;
     private boolean sslEnabled;
     private boolean persistenceEnabled;
+
     private long cacheSizeBytes;
     private LocalCacheSettings cacheSettings;
 
@@ -319,6 +320,12 @@ public long getCacheSizeBytes() {
       if (cacheSettings instanceof PersistentCacheSettings) {
         return ((PersistentCacheSettings) cacheSettings).getSizeBytes();
       } else {
+        MemoryCacheSettings memorySettings = (MemoryCacheSettings) cacheSettings;
+        if (memorySettings.getGarbageCollectorSettings() instanceof MemoryLruGcSettings) {
+          return ((MemoryLruGcSettings) memorySettings.getGarbageCollectorSettings())
+              .getSizeBytes();
+        }
+
         return CACHE_SIZE_UNLIMITED;
       }
     }

firebase-firestore/src/main/java/com/google/firebase/firestore/MemoryCacheSettings.java

@@ -27,42 +27,58 @@
  * `FirebaseFirestoreSettings` instance to configure Firestore SDK.
  */
 public final class MemoryCacheSettings implements LocalCacheSettings {
+  private MemoryGarbageCollectorSettings gcSettings;
 
   /** Returns a new instance of {@link MemoryCacheSettings.Builder} with default configurations. */
   @NonNull
   public static MemoryCacheSettings.Builder newBuilder() {
     return new MemoryCacheSettings.Builder();
   }
 
-  private MemoryCacheSettings() {}
+  private MemoryCacheSettings(MemoryGarbageCollectorSettings settings) {
+    gcSettings = settings;
+  }
 
   @Override
   public int hashCode() {
-    return super.hashCode();
+    return gcSettings.hashCode();
   }
 
   @Override
   public boolean equals(@Nullable Object obj) {
     if (this == obj) return true;
     if (obj == null || getClass() != obj.getClass()) return false;
 
-    return true;
+    return getGarbageCollectorSettings()
+        .equals(((MemoryCacheSettings) obj).getGarbageCollectorSettings());
   }
 
   @Override
   public String toString() {
-    return "MemoryCacheSettings{}";
+    return "MemoryCacheSettings{gcSettings=" + getGarbageCollectorSettings() + "}";
+  }
+
+  @NonNull
+  public MemoryGarbageCollectorSettings getGarbageCollectorSettings() {
+    return gcSettings;
   }
 
   /** A Builder for creating {@code MemoryCacheSettings} instance. */
   public static class Builder {
+    private MemoryGarbageCollectorSettings gcSettings = MemoryEagerGcSettings.newBuilder().build();
 
     private Builder() {}
 
     /** Creates a {@code MemoryCacheSettings} instance. */
     @NonNull
     public MemoryCacheSettings build() {
-      return new MemoryCacheSettings();
+      return new MemoryCacheSettings(gcSettings);
+    }
+
+    @NonNull
+    public Builder setGcSettings(@NonNull MemoryGarbageCollectorSettings gcSettings) {
+      this.gcSettings = gcSettings;
+      return this;
     }
   }
 }

firebase-firestore/src/main/java/com/google/firebase/firestore/MemoryEagerGcSettings.java

@@ -0,0 +1,55 @@
+// Copyright 2023 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.firebase.firestore;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+
+public final class MemoryEagerGcSettings implements MemoryGarbageCollectorSettings {
+  private MemoryEagerGcSettings() {}
+
+  public static class Builder {
+    private Builder() {}
+
+    @NonNull
+    public MemoryEagerGcSettings build() {
+      return new MemoryEagerGcSettings();
+    }
+  }
+
+  @Override
+  public int hashCode() {
+    return super.hashCode();
+  }
+
+  @Override
+  public boolean equals(@Nullable Object obj) {
+    if (this == obj) return true;
+    if (obj == null || getClass() != obj.getClass()) return false;
+
+    return true;
+  }
+
+  @NonNull
+  @Override
+  public String toString() {
+    return "MemoryEagerGcSettings{}";
+  }
+
+  @NonNull
+  public static MemoryEagerGcSettings.Builder newBuilder() {
+    return new Builder();
+  }
+}

firebase-firestore/src/main/java/com/google/firebase/firestore/MemoryGarbageCollectorSettings.java

@@ -0,0 +1,17 @@
+// Copyright 2023 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.firebase.firestore;
+
+public interface MemoryGarbageCollectorSettings {}

firebase-firestore/src/main/java/com/google/firebase/firestore/MemoryLruGcSettings.java

@@ -0,0 +1,71 @@
+// Copyright 2023 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.firebase.firestore;
+
+import androidx.annotation.NonNull;
+
+public final class MemoryLruGcSettings implements MemoryGarbageCollectorSettings {
+
+  private long sizeBytes;
+
+  public static class Builder {
+    private long sizeBytes = FirebaseFirestoreSettings.DEFAULT_CACHE_SIZE_BYTES;
+
+    private Builder() {}
+
+    @NonNull
+    public MemoryLruGcSettings build() {
+      return new MemoryLruGcSettings(sizeBytes);
+    }
+
+    public void setSizeBytes(long size) {
+      sizeBytes = size;
+    }
+  }
+
+  private MemoryLruGcSettings(long size) {
+    sizeBytes = size;
+  }
+
+  @NonNull
+  public static MemoryLruGcSettings.Builder newBuilder() {
+    return new Builder();
+  }
+
+  public long getSizeBytes() {
+    return sizeBytes;
+  }
+
+  @Override
+  public boolean equals(Object o) {
+    if (this == o) return true;
+    if (o == null || getClass() != o.getClass()) return false;
+
+    MemoryLruGcSettings that = (MemoryLruGcSettings) o;
+
+    return sizeBytes == that.sizeBytes;
+  }
+
+  @Override
+  public int hashCode() {
+    return (int) (sizeBytes ^ (sizeBytes >>> 32));
+  }
+
+  @NonNull
+  @Override
+  public String toString() {
+    return "MemoryLruGcSettings{cacheSize=" + getSizeBytes() + "}";
+  }
+}