Merge pull request #29 from indigotech/feature/refactor-enum

Feature - EnumType and UnionType refactor

Author: felipesabino

src/decorator.ts

@@ -15,9 +15,7 @@ export const GQ_QUERY_KEY = 'gq_query';
 export const GQ_MUTATION_KEY = 'gq_mutation';
 export const GQ_SUBSCRIPTION_KEY = 'gq_subscription';
 export const GQ_FIELDS_KEY = 'gq_fields';
-export const GQ_VALUES_KEY = 'gq_values';
 export const GQ_OBJECT_METADATA_KEY = 'gq_object_type';
-export const GQ_ENUM_METADATA_KEY = 'gq_enum_type';
 export const GQ_DESCRIPTION_KEY = 'gq_description';
 
 export interface TypeMetadata {
@@ -54,18 +52,6 @@ export interface ObjectTypeMetadata {
     isInput?: boolean;
 }
 
-export interface EnumTypeMetadata {
-    name?: string;
-    description?: string;
-    values?: EnumValueMetadata[];
-}
-
-export interface EnumValueMetadata {
-    name: string;
-    value?: any;
-    description?: string;
-}
-
 export interface DefaultOption {
     description?: string;
 }
@@ -119,32 +105,6 @@ function createOrSetObjectTypeMetadata(target: any, metadata: ObjectTypeMetadata
     }
 }
 
-function createOrSetEnumTypeMetadata(target: any, metadata: EnumTypeMetadata) {
-    if (!Reflect.hasMetadata(GQ_ENUM_METADATA_KEY, target.prototype)) {
-        let mergedMetadata = mergeDescriptionMetadata(target, metadata);
-        Reflect.defineMetadata(GQ_ENUM_METADATA_KEY, mergedMetadata, target.prototype);
-    } else {
-        const originalMetadata = Reflect.getMetadata(GQ_ENUM_METADATA_KEY, target.prototype) as EnumTypeMetadata;
-        Object.assign(originalMetadata, metadata);
-    }
-}
-
-function createOrSetValueTypeMetadata(target: any, metadata: EnumValueMetadata) {
-    let valueDefs: EnumValueMetadata[];
-    if (!Reflect.hasMetadata(GQ_VALUES_KEY, target)) {
-        valueDefs = [];
-        Reflect.defineMetadata(GQ_VALUES_KEY, valueDefs, target);
-    } else {
-        valueDefs = Reflect.getMetadata(GQ_VALUES_KEY, target);
-    }
-    const def = valueDefs.find(d => d.name === metadata.name);
-    if (!def) {
-        let propertyDescriptionMetadata = getPropertyDescriptionMetadata(target, metadata.name);
-        Object.assign(metadata, propertyDescriptionMetadata);
-        valueDefs.push(metadata);
-    }
-}
-
 function createOrSetFieldTypeMetadata(target: any, metadata: FieldTypeMetadata) {
     let fieldDefs: FieldTypeMetadata[];
     if (!Reflect.hasMetadata(GQ_FIELDS_KEY, target)) {
@@ -202,13 +162,6 @@ export function getFieldMetadata(target: any, name: string) {
     return (<FieldTypeMetadata[]>Reflect.getMetadata(GQ_FIELDS_KEY, target)).find(m => m.name === name);
 }
 
-export function getValueMetadata(target: any, name: string) {
-    if (!Reflect.hasMetadata(GQ_VALUES_KEY, target)) {
-        return null;
-    }
-    return (<EnumValueMetadata[]>Reflect.getMetadata(GQ_VALUES_KEY, target)).find(m => m.name === name);
-}
-
 function setArgumentMetadata(target: any, propertyKey: any, index: number, metadata: ArgumentMetadata) {
     const fieldMetadata = getFieldMetadata(target, propertyKey);
     if (fieldMetadata && fieldMetadata.args && fieldMetadata.args[index]) {
@@ -258,11 +211,6 @@ function setDescriptionMetadata(description: string, target: any, propertyKey: s
                 name: propertyKey,
                 description: description,
             });
-        } else if (getValueMetadata(target, propertyKey) != null) {
-            createOrSetValueTypeMetadata(target, {
-                name: propertyKey,
-                description: description,
-            });
         } else {
             createPropertyDescriptionMetadata(target, description, propertyKey);
         }
@@ -271,10 +219,6 @@ function setDescriptionMetadata(description: string, target: any, propertyKey: s
             createOrSetObjectTypeMetadata(target, {
                 description: description,
             });
-        } else if (Reflect.hasMetadata(GQ_ENUM_METADATA_KEY, target.prototype)) {
-            createOrSetEnumTypeMetadata(target, {
-                description: description,
-            });
         } else {
             createDescriptionMetadata(target, description);
         }
@@ -321,22 +265,6 @@ function setPaginationMetadata(target: any, propertyKey: string, methodDescripto
     };
 }
 
-
-export function EnumType(option?: DefaultOption) {
-    return function (target: any) {
-        createOrSetEnumTypeMetadata(target, {
-            name: target.name,
-        });
-
-        if (option) {
-            // description
-            if (option.description) {
-                setDescriptionMetadata(option.description, target);
-            }
-        }
-    } as Function;
-}
-
 export function ObjectType(option?: DefaultOption) {
     return function (target: any) {
         createOrSetObjectTypeMetadata(target, {
@@ -415,22 +343,6 @@ export function Field(option?: FieldOption) {
     } as Function;
 }
 
-export function Value(value?: any, option?: DefaultOption) {
-    return function (target: any, propertyKey: any) {
-        createOrSetValueTypeMetadata(target, {
-            name: propertyKey,
-            value: value,
-        });
-
-        if (option) {
-            // description
-            if (option.description) {
-                setDescriptionMetadata(option.description, target, propertyKey);
-            }
-        }
-    } as Function;
-}
-
 export function NonNull() {
     return function (target: any, propertyKey: any, index?: number) {
         setNonNullMetadata(target, propertyKey, index);

src/decorator/enum-type.decorator.ts

@@ -0,0 +1,48 @@
+import { EnumOption, EnumValueOption } from '../metadata';
+import { getMetadataArgsStorage } from '../metadata-builder';
+
+/**
+ * It can be used just like {@link ObjectType} in order to create {@link GraphQLEnumType} objects.
+ * See [GraphQL Documentation - Enum Types]{@http://graphql.org/learn/schema/#enumeration-types}
+ *
+ * @param option Options for a Enum Type
+ */
+export function EnumType(option?: EnumOption) {
+  return function (target: any) {
+    getMetadataArgsStorage().enums.push({
+      target: target,
+      name: target.name,
+      description: option ? option.description : null,
+    });
+  } as Function;
+}
+
+/**
+ * Used to define a value for an {@link EnumType} definition.
+ *
+ * Example usage:
+ *
+ * ```typescript
+ * @EnumType()
+ * class MyEnum {
+ *   @Value('1', {description: 'Value One'})
+ *   VALUE_ONE: string;
+ *
+ *   @Value('2', {description: 'Value Two'})
+ *   VALUE_TWO: string;
+ * }
+ *```
+ *
+ * @param value Value to be assigned to the property at schema level
+ * @param option Options for a Enum Value
+ */
+export function Value(value: any, option?: EnumValueOption) {
+  return function (target: any, propertyKey: any, methodDescriptor: any) {
+    getMetadataArgsStorage().enumValues.push({
+      target: target,
+      name: propertyKey,
+      value: value,
+      description: option ? option.description : null,
+    });
+  } as Function;
+}

src/decorator/index.ts

@@ -1 +1,2 @@
+export * from './enum-type.decorator';
 export * from './union-type.decorator';

src/decorator/union-type.decorator.ts

@@ -1,13 +1,16 @@
-import { MetadataStorage } from '../metadata-storage';
+import { getMetadataArgsStorage } from '../metadata-builder';
 import { UnionOption } from '../metadata';
 
 /**
- * Union Type. ref: http://graphql.org/learn/schema/#union-types
+ * Union Type.
+ * See [GraphQL Documentation - Union Types]{@link http://graphql.org/learn/schema/#union-types}
+ *
  * @param option Options for a Union Type
  */
 export function UnionType<T>(option: UnionOption<T>) {
   return function (target: any) {
-      MetadataStorage.addUnionMetadata({
+    getMetadataArgsStorage().union.push({
+          target: target,
           name: target.name,
           types: option.types,
           resolver: option.resolver,

src/enum.type-factory.ts

@@ -4,23 +4,21 @@ import {
     ArgumentMetadata,
     ContextMetadata,
     FieldTypeMetadata,
-    GQ_ENUM_METADATA_KEY,
     GQ_FIELDS_KEY,
     GQ_OBJECT_METADATA_KEY,
     Middleware,
     RootMetadata,
     TypeMetadata,
 } from './decorator';
-import { MetadataStorage } from './metadata-storage';
+import { getMetadataArgsStorage } from './metadata-builder';
 
 import { SchemaFactoryError, SchemaFactoryErrorType } from './schema_factory';
 
 import { IoCContainer } from './ioc-container';
 import { OrderByTypeFactory } from './order-by.type-factory';
 import { PaginationType } from './pagination.type';
-import { enumTypeFactory } from './enum.type-factory';
 import { objectTypeFactory } from './object_type_factory';
-import { unionTypeFactory } from './type-factory';
+import { unionTypeFactory, enumTypeFactory } from './type-factory';
 
 
 export interface ResolverHolder {
@@ -53,13 +51,12 @@ function convertType(typeFn: Function, metadata: TypeMetadata, isInput: boolean,
       } else {
         returnType = metadata.explicitType;
 
-        if (returnType && returnType.prototype && MetadataStorage.containsUnionMetadata(returnType.name)) {
-            returnType = unionTypeFactory(returnType.name, isInput);
+        if (returnType && returnType.prototype && getMetadataArgsStorage().filterUnionTypeByClass(returnType).length > 0) {
+            returnType = unionTypeFactory(returnType, isInput);
         } else if (returnType && returnType.prototype && Reflect.hasMetadata(GQ_OBJECT_METADATA_KEY, returnType.prototype)) {
             // recursively call objectFactory
             returnType = objectTypeFactory(returnType, isInput);
-        } else if (returnType && returnType.prototype && Reflect.hasMetadata(GQ_ENUM_METADATA_KEY, returnType.prototype)) {
-            let enumMetadata = Reflect.getMetadata(GQ_ENUM_METADATA_KEY, returnType.prototype);
+        } else if (returnType && returnType.prototype && getMetadataArgsStorage().filterEnumsByClass(returnType).length > 0) {
             returnType = enumTypeFactory(returnType);
         }
     }

src/field_type_factory.ts

@@ -0,0 +1,2 @@
+export * from './metadata-args.storage';
+export * from './metadata.builder';

src/metadata-builder/index.ts

@@ -0,0 +1,36 @@
+import {
+  EnumTypeArg,
+  EnumValueArg,
+  UnionTypeArgs,
+} from '../metadata/args';
+
+/**
+ * Gets metadata args storage.
+ * Metadata args storage follows the best practices and stores metadata in a global variable.
+ */
+export function getMetadataArgsStorage(): MetadataArgsStorage {
+  if (!(global as any).graphqlSchemaMetadataArgsStorage) {
+      (global as any).graphqlSchemaMetadataArgsStorage = new MetadataArgsStorage();
+  }
+
+  return (global as any).graphqlSchemaMetadataArgsStorage;
+}
+
+export class MetadataArgsStorage {
+  enums: EnumTypeArg[] = [];
+  enumValues: EnumValueArg[] = [];
+  union: UnionTypeArgs[] = [];
+
+  filterEnumsByClass(target: any): EnumTypeArg[] {
+    return this.enums.filter(item => item.target === target);
+  }
+
+  filterEnumValuesByClass(target: any): EnumValueArg[] {
+    return this.enumValues.filter(item => item.target === target.prototype);
+  }
+
+  filterUnionTypeByClass(target: any): UnionTypeArgs[] {
+    return this.union.filter(item => item.target === target);
+  }
+}
+

src/metadata-builder/metadata-args.storage.ts

@@ -0,0 +1,57 @@
+import {
+  EnumTypeMetadata,
+  EnumValueMetadata,
+  UnionTypeMetadata,
+} from '../metadata/types';
+
+import { getMetadataArgsStorage } from './metadata-args.storage';
+
+/**
+ * Gets metadata builder
+ * Metadata builder follows the best practices and stores metadata in a global variable.
+ */
+export function getMetadataBuilder(): MetadataBuilder {
+  if (!(global as any).graphqlSchemaMetadataBuilder) {
+      (global as any).graphqlSchemaMetadataBuilder = new MetadataBuilder();
+  }
+
+  return (global as any).graphqlSchemaMetadataBuilder;
+}
+
+export class MetadataBuilder {
+
+  buildEnumMetadata(target: any): EnumTypeMetadata[] | undefined {
+    return getMetadataArgsStorage()
+      .filterEnumsByClass(target)
+      .map(enumArg => ({
+        target: enumArg.target,
+        name: enumArg.name,
+        description: enumArg.description,
+        values: this.buildEnumValueMetadata(target),
+      }));
+  }
+
+  buildUnionTypeMetadata(target: any): UnionTypeMetadata[] | undefined {
+    return getMetadataArgsStorage()
+      .filterUnionTypeByClass(target)
+      .map(unionArg => ({
+        target: unionArg.target,
+        name: unionArg.name,
+        resolver: unionArg.resolver,
+        types: unionArg.types,
+        description: unionArg.description,
+      }));
+  }
+
+  protected buildEnumValueMetadata(target: any): EnumValueMetadata[] | undefined {
+    return getMetadataArgsStorage()
+      .filterEnumValuesByClass(target)
+      .map(enumValueArg => ({
+        target: enumValueArg.target,
+        name: enumValueArg.name,
+        value: enumValueArg.value,
+        description: enumValueArg.description,
+      }));
+  }
+
+}