feat(memory): use WeakMap instead normal Map to allow GC

MichalLytek · Dec 22, 2019 · a195e8a · a195e8a
1 parent 9568cfd
commit a195e8a
Show file tree

Hide file tree

Showing 3 changed files with 16 additions and 10 deletions.
diff --git a/packages/core/src/metadata/builder/MetadataBuilder.ts b/packages/core/src/metadata/builder/MetadataBuilder.ts
@@ -8,7 +8,7 @@ import MissingClassMetadataError from "@src/errors/MissingClassMetadataError";
 import MissingFieldsError from "@src/errors/MissingFieldsError";
 
 export default class MetadataBuilder {
-  private readonly typeMetadataByClassMap = new Map<
+  private readonly typeMetadataByClassMap = new WeakMap<
     ClassType,
     BuiltObjectTypeMetadata
   >();
@@ -30,7 +30,7 @@ export default class MetadataBuilder {
     const objectTypeFieldsMetadata = MetadataStorage.get().findFieldMetadata(
       typeClass,
     );
-    if (objectTypeFieldsMetadata.length === 0) {
+    if (!objectTypeFieldsMetadata || objectTypeFieldsMetadata.length === 0) {
       throw new MissingFieldsError(typeClass);
     }
 

diff --git a/packages/core/src/metadata/storage/MetadataStorage.ts b/packages/core/src/metadata/storage/MetadataStorage.ts
@@ -3,8 +3,11 @@ import FieldMetadata from "@src/metadata/storage/definitions/FieldMetadata";
 import ClassType from "@src/interfaces/ClassType";
 
 export default class MetadataStorage {
-  protected objectTypesMetadata: ObjectTypeMetadata[] = [];
-  protected fieldsMetadata: FieldMetadata[] = [];
+  protected objectTypesMetadataMap = new WeakMap<
+    ClassType,
+    ObjectTypeMetadata
+  >();
+  protected fieldsMetadataMap = new WeakMap<ClassType, FieldMetadata[]>();
 
   protected constructor() {}
 
@@ -16,16 +19,19 @@ export default class MetadataStorage {
   }
 
   collectObjectTypeMetadata(metadata: ObjectTypeMetadata): void {
-    this.objectTypesMetadata.push(metadata);
+    this.objectTypesMetadataMap.set(metadata.target, metadata);
   }
   findObjectTypeMetadata(typeClass: ClassType): ObjectTypeMetadata | undefined {
-    return this.objectTypesMetadata.find(it => it.target === typeClass);
+    return this.objectTypesMetadataMap.get(typeClass);
   }
 
   collectFieldMetadata(metadata: FieldMetadata): void {
-    this.fieldsMetadata.push(metadata);
+    this.fieldsMetadataMap.set(metadata.target, [
+      ...(this.fieldsMetadataMap.get(metadata.target) ?? []),
+      metadata,
+    ]);
   }
-  findFieldMetadata(typeClass: ClassType): FieldMetadata[] {
-    return this.fieldsMetadata.filter(it => it.target === typeClass);
+  findFieldMetadata(typeClass: ClassType): FieldMetadata[] | undefined {
+    return this.fieldsMetadataMap.get(typeClass);
   }
 }
diff --git a/packages/core/src/schema/SchemaGenerator.ts b/packages/core/src/schema/SchemaGenerator.ts
@@ -23,7 +23,7 @@ import {
 } from "@src/metadata/storage/definitions/common";
 
 export default class SchemaGenerator {
-  private readonly typeByClassMap = new Map<ClassType, GraphQLObjectType>();
+  private readonly typeByClassMap = new WeakMap<ClassType, GraphQLObjectType>();
   private readonly metadataBuilder: MetadataBuilder;
 
   constructor(private readonly buildSchemaOptions: BuildSchemaOptions) {