implemeneted resolvable fields

packages/@aws-cdk/aws-appsync/lib/graphqlapi.ts

@@ -6,7 +6,7 @@ import { IFunction } from '@aws-cdk/aws-lambda';
 import { Construct, Duration, IResolvable, Stack } from '@aws-cdk/core';
 import { CfnApiKey, CfnGraphQLApi, CfnGraphQLSchema } from './appsync.generated';
 import { DynamoDbDataSource, HttpDataSource, LambdaDataSource, NoneDataSource } from './data-source';
-import { ObjectType, ObjectTypeProps } from './schema-types';
+import { ObjectType, ObjectTypeProps, InterfaceType } from './schema-types';
 
 /**
  * enum with all possible values for AppSync authorization type
@@ -715,7 +715,7 @@ export class GraphQLApi extends Construct {
    * @param delimiter the delimiter between schema and addition
    * @default - ''
    */
-  public appendToSchema(addition: string | ObjectType, delimiter?: string): void {
+  public appendToSchema(addition: string | ObjectType | InterfaceType, delimiter?: string): void {
     if ( this.schemaMode != SchemaDefinition.CODE ) {
       throw new Error('API cannot append to schema because schema definition mode is not configured as CODE.');
     }

packages/@aws-cdk/aws-appsync/lib/index.ts

@@ -5,4 +5,5 @@ export * from './data-source';
 export * from './mapping-template';
 export * from './resolver';
 export * from './schema-types';
+export * from './schema-utils';
 export * from './graphqlapi';

packages/@aws-cdk/aws-appsync/lib/schema-types.ts

@@ -1,153 +1,6 @@
-/**
- * Directives for types
- *
- * i.e. @aws_iam or @aws_subscribe
- */
-export class Directive {
-  /**
-   * Add the @aws_iam directive
-   */
-  public static iam(): Directive{
-    return new Directive('@aws_iam');
-  }
-
-  /**
-   * Add a custom directive
-   *
-   * @param statement - the directive statement to append
-   * Note: doesn't guarantee functionality
-   */
-  public static custom(statement: string): Directive {
-    return new Directive(statement);
-  }
-
-  /**
-   * the directive statement
-   */
-  public readonly statement: string;
-
-  private constructor(statement: string) { this.statement = statement; }
-}
-
-/**
- * Properties for configuring an type
- *
- * @param definition - the variables and types that define this type
- * i.e. { string: GraphqlType, string: GraphqlType }
- */
-export interface BaseTypeProps {
-  /**
-   * the attributes of this type
-   */
-  readonly definition: { [key: string]: GraphqlType };
-}
-
-/**
- * Properties for configuring an Interface Type
- */
-export class InterfaceType {
-  /**
-   * the name of this type
-   */
-  public readonly name: string;
-  /**
-   * the attributes of this type
-   */
-  public readonly definition: { [key: string]: GraphqlType };
-
-  public constructor(name: string, props: BaseTypeProps) {
-    this.name = name;
-    this.definition = props.definition;
-  }
-}
-
-/**
- * Properties for configuring an Object Type
- *
- * @param definition - the variables and types that define this type
- * i.e. { string: GraphqlType, string: GraphqlType }
- * @param directives - the directives for this object type
- */
-export interface ObjectTypeProps extends BaseTypeProps {
-  /**
-   * the directives for this object type
-   *
-   * @default - no directives
-   */
-  readonly directives?: Directive [];
-}
-
-/**
- * Object Types are types declared by you.
- */
-export class ObjectType extends InterfaceType {
-  /**
-   * A method to define Object Types from an interface
-   */
-  public static fromInterface(name: string, interfaceType: InterfaceType, props: ObjectTypeProps): ObjectType {
-    return new ObjectType(name, {
-      definition: Object.assign({}, props.definition, interfaceType.definition),
-      directives: props.directives,
-    });
-  }
-  /**
-   * the directives for this object type
-   *
-   * @default - no directives
-   */
-  public readonly directives?: Directive[];
-
-  public constructor(name: string, props: ObjectTypeProps) {
-    super(name, props);
-    this.directives = props.directives;
-  }
-
-  /**
-   * Create an GraphQL Type representing this Object Type
-   *
-   * @param options the options to configure this attribute
-   * - isList
-   * - isRequired
-   * - isRequiredList
-   */
-  public attribute(options?: BaseGraphqlTypeOptions): GraphqlType{
-    return GraphqlType.graphqlObject({
-      isList: options?.isList,
-      isRequired: options?.isRequired,
-      isRequiredList: options?.isRequiredList,
-      objectType: this,
-    });
-  }
-
-  /**
-   * Generate the string of this object type
-   */
-  public toString(): string {
-    const directives = this.generateDirectives(this.directives);
-    let schemaAddition = `type ${this.name} ${directives}{\n`;
-    Object.keys(this.definition).forEach( (key) => {
-      const attribute = this.definition[key];
-      schemaAddition = `${schemaAddition}  ${key}: ${attribute.toString()}\n`;
-    });
-    return `${schemaAddition}}`;
-  }
-
-  /**
-   * Utility function to generate directives
-   *
-   * @param directives the directives of a given type
-   * @param delimiter the separator betweeen directives
-   * @default - ' '
-   */
-  private generateDirectives(directives?: Directive[], delimiter?: string): string{
-    let schemaAddition = '';
-    if (!directives){ return schemaAddition; }
-    directives.map((directive) => {
-      schemaAddition = `${schemaAddition}${directive.statement}${delimiter ?? ' '}`;
-    });
-    return schemaAddition;
-  }
-}
+import { Resolver } from './resolver';
+import { Directive, Type, ResolvableField, ResolvableFieldOptions } from './schema-utils';
+import { BaseDataSource } from './data-source';
 
 /**
  * Base options for GraphQL Types
@@ -457,89 +310,173 @@ export class GraphqlType {
 }
 
 /**
- * Enum containing the Types that can be used to define ObjectTypes
+ * Properties for configuring an type
+ *
+ * @param definition - the variables and types that define this type
+ * i.e. { string: GraphqlType, string: GraphqlType }
  */
-export enum Type {
-  /**
-   * `ID` scalar type is a unique identifier. `ID` type is serialized similar to `String`.
-   *
-   * Often used as a key for a cache and not intended to be human-readable.
-   */
-  ID = 'ID',
-  /**
-   * `String` scalar type is a free-form human-readable text.
-   */
-  STRING = 'String',
+export interface BaseTypeProps {
   /**
-   * `Int` scalar type is a signed non-fractional numerical value.
+   * the attributes of this type
    */
-  INT = 'Int',
+  readonly definition: { [key: string]: GraphqlType | ResolvableField };
+}
+
+/**
+ * Properties for configuring an Interface Type
+ */
+export class InterfaceType {
   /**
-   * `Float` scalar type is a signed double-precision fractional value.
+   * the name of this type
    */
-  FLOAT = 'Float',
+  public readonly name: string;
   /**
-   * `Boolean` scalar type is a boolean value: true or false.
+   * the attributes of this type
    */
-  BOOLEAN = 'Boolean',
+  public readonly definition: { [key: string]: GraphqlType | ResolvableField };
+
+  public constructor(name: string, props: BaseTypeProps) {
+    this.name = name;
+    this.definition = props.definition;
+  }
 
   /**
-   * `AWSDate` scalar type represents a valid extended `ISO 8601 Date` string.
-   *
-   * In other words, accepts date strings in the form of `YYYY-MM-DD`. It accepts time zone offsets.
-   *
-   * @see https://en.wikipedia.org/wiki/ISO_8601#Calendar_dates
+   * Generate the string of this object type
    */
-  AWS_DATE = 'AWSDate',
+  public toString(): string {
+    let schemaAddition = `interface ${this.name}{\n`;
+    Object.keys(this.definition).forEach( (key) => {
+      const attribute = this.definition[key];
+      schemaAddition = `${schemaAddition}  ${key}: ${attribute.toString()}\n`;
+    });
+    return `${schemaAddition}}`;
+  }
+}
+
+/**
+ * Properties for configuring an Object Type
+ *
+ * @param definition - the variables and types that define this type
+ * i.e. { string: GraphqlType, string: GraphqlType }
+ * @param directives - the directives for this object type
+ */
+export interface ObjectTypeProps extends BaseTypeProps {
   /**
-   * `AWSTime` scalar type represents a valid extended `ISO 8601 Time` string.
-   *
-   * In other words, accepts date strings in the form of `hh:mm:ss.sss`. It accepts time zone offsets.
+   * the directives for this object type
    *
-   * @see https://en.wikipedia.org/wiki/ISO_8601#Times
+   * @default - no directives
    */
-  AWS_TIME = 'AWSTime',
+  readonly directives?: Directive[];
+}
+
+/**
+ * Object Types are types declared by you.
+ */
+export class ObjectType extends InterfaceType {
   /**
-   * `AWSDateTime` scalar type represents a valid extended `ISO 8601 DateTime` string.
-   *
-   * In other words, accepts date strings in the form of `YYYY-MM-DDThh:mm:ss.sssZ`. It accepts time zone offsets.
-   *
-   * @see https://en.wikipedia.org/wiki/ISO_8601#Combined_date_and_time_representations
+   * A method to define Object Types from an interface
    */
-  AWS_DATE_TIME = 'AWSDateTime',
+  public static fromInterface(name: string, interfaceType: InterfaceType, props: ObjectTypeProps): ObjectType {
+    return new ObjectType(name, {
+      definition: Object.assign({}, props.definition, interfaceType.definition),
+      directives: props.directives,
+    });
+  }
   /**
-   * `AWSTimestamp` scalar type represents the number of seconds since `1970-01-01T00:00Z`.
+   * the directives for this object type
    *
-   * Timestamps are serialized and deserialized as numbers.
+   * @default - no directives
    */
-  AWS_TIMESTAMP = 'AWSTimestamp',
+  public readonly directives?: Directive[];
   /**
-   * `AWSEmail` scalar type represents an email address string (i.e.`username@example.com`)
+   * The resolvers linked to this data source
    */
-  AWS_EMAIL = 'AWSEmail',
+  public resolvers?: Resolver[];
+
+  public constructor(name: string, props: ObjectTypeProps) {
+    super(name, props);
+    this.directives = props.directives;
+
+    Object.keys(this.definition).forEach((fieldName) => {
+      const fieldInfo = this.definition[fieldName];
+      if(fieldInfo instanceof ResolvableField) {
+        this.resolvers?.push(this.generateResolver(fieldName, fieldInfo));
+      }
+    });
+  }
+
   /**
-   * `AWSJson` scalar type represents a JSON string.
+   * Create an GraphQL Type representing this Object Type
+   *
+   * @param options the options to configure this attribute
+   * - isList
+   * - isRequired
+   * - isRequiredList
    */
-  AWS_JSON = 'AWSJSON',
+  public attribute(options?: BaseGraphqlTypeOptions): GraphqlType{
+    return GraphqlType.graphqlObject({
+      isList: options?.isList,
+      isRequired: options?.isRequired,
+      isRequiredList: options?.isRequiredList,
+      objectType: this,
+    });
+  }
+
   /**
-   * `AWSURL` scalar type represetns a valid URL string.
+   * Add a resolvable field to this Object Type
    *
-   * URLs wihtout schemes or contain double slashes are considered invalid.
+   * @param fieldName -
+   * @param type -
+   * @param dataSource -
+   * @param options -
    */
-  AWS_URL = 'AWSURL',
+  public addResolvableField(fieldName: string, type: GraphqlType, dataSource: BaseDataSource, options?: ResolvableFieldOptions): Resolver{
+    const resolvableField = new ResolvableField(type, dataSource, options);
+    const resolver = this.generateResolver(fieldName, resolvableField);
+    this.resolvers?.push(resolver);
+    this.definition[fieldName] = resolvableField;
+    return resolver;
+  }
+
   /**
-   * `AWSPhone` scalar type represents a valid phone number. Phone numbers maybe be whitespace delimited or hyphenated.
-   *
-   * The number can specify a country code at the beginning, but is not required for US phone numbers.
+   * Generate the string of this object type
    */
-  AWS_PHONE = 'AWSPhone',
+  public toString(): string {
+    const directives = this.generateDirectives(this.directives);
+    let schemaAddition = `type ${this.name} ${directives}{\n`;
+    Object.keys(this.definition).forEach( (key) => {
+      const attribute = this.definition[key];
+      const args = attribute instanceof ResolvableField ? attribute.argsToString() : '';
+      schemaAddition = `${schemaAddition}  ${key}${args}: ${attribute.toString()}\n`;
+    });
+    return `${schemaAddition}}`;
+  }
+
   /**
-   * `AWSIPAddress` scalar type respresents a valid `IPv4` of `IPv6` address string.
+   * Utility function to generate directives
+   *
+   * @param directives the directives of a given type
+   * @param delimiter the separator betweeen directives
+   * @default - ' '
    */
-  AWS_IP_ADDRESS = 'AWSIPAddress',
+  private generateDirectives(directives?: Directive[], delimiter?: string): string{
+    let schemaAddition = '';
+    if (!directives){ return schemaAddition; }
+    directives.map((directive) => {
+      schemaAddition = `${schemaAddition}${directive.statement}${delimiter ?? ' '}`;
+    });
+    return schemaAddition;
+  }
 
   /**
-   * Type used for Object Types
+   * Generate the resolvers linked to this Object Type
    */
-  OBJECT = 'OBJECT',
+  protected generateResolver(fieldName: string, resolvableField: ResolvableField): Resolver{
+    return resolvableField.dataSource.createResolver({
+      typeName: this.name,
+      fieldName: fieldName,
+      requestMappingTemplate: resolvableField.requestMappingTemplate,
+      responseMappingTemplate: resolvableField.responseMappingTemplate,
+    });
+  }
 }

packages/@aws-cdk/aws-appsync/lib/schema-utils.ts

@@ -0,0 +1,221 @@
+import { BaseDataSource } from './data-source';
+import { MappingTemplate } from './mapping-template';
+import { GraphqlType } from './schema-types';
+
+/**
+ * Directives for types
+ *
+ * i.e. @aws_iam or @aws_subscribe
+ */
+export class Directive {
+  /**
+   * Add the @aws_iam directive
+   */
+  public static iam(): Directive{
+    return new Directive('@aws_iam');
+  }
+
+  /**
+   * Add a custom directive
+   *
+   * @param statement - the directive statement to append
+   * Note: doesn't guarantee functionality
+   */
+  public static custom(statement: string): Directive {
+    return new Directive(statement);
+  }
+
+  /**
+   * the directive statement
+   */
+  public readonly statement: string;
+
+  private constructor(statement: string) { this.statement = statement; }
+}
+
+/**
+ * Properties for configuring a resolvable field
+ *
+ * @options args - the variables and types that define the arguments
+ *
+ * i.e. { string: GraphqlType, string: GraphqlType }
+ *
+ * @options requestMappingTemplate - the mapping template for requests to this resolver
+ * @options responseMappingTemplate - the mapping template for responses from this resolver
+ */
+export interface ResolvableFieldOptions {
+  /**
+   * The arguments for this resolvable field.
+   *
+   * i.e. type Example (first: String second: String) {}
+   * - where 'first' and 'second' are key values for args
+   * and 'String' is the GraphqlType
+   *
+   * @default - no arguments
+   */
+  readonly args?: { [key: string]: GraphqlType };
+  /**
+   * The request mapping template for this resolver
+   *
+   * @default - No mapping template
+   */
+  readonly requestMappingTemplate?: MappingTemplate;
+  /**
+   * The response mapping template for this resolver
+   *
+   * @default - No mapping template
+   */
+  readonly responseMappingTemplate?: MappingTemplate;
+}
+
+/**
+ * Resolvable Fields build upon Graphql Types and provide fields
+ * that can resolve into operations on a data source.
+ */
+export class ResolvableField {
+  /**
+   * The return type for this field
+   */
+  readonly graphqlType: GraphqlType;
+  /**
+   * The data source creating linked to this resolvable field
+   */
+  readonly dataSource: BaseDataSource;
+  /**
+   * The arguments for this resolvable field.
+   *
+   * i.e. type Example (first: String second: String) {}
+   * - where 'first' and 'second' are key values for args
+   * and 'String' is the GraphqlType
+   *
+   * @default - no arguments
+   */
+  readonly args?: { [key: string]: GraphqlType };
+  /**
+   * The request mapping template for this resolver
+   *
+   * @default - No mapping template
+   */
+  readonly requestMappingTemplate?: MappingTemplate;
+  /**
+   * The response mapping template for this resolver
+   *
+   * @default - No mapping template
+   */
+  readonly responseMappingTemplate?: MappingTemplate;
+
+  public constructor(type: GraphqlType, dataSource: BaseDataSource, options?: ResolvableFieldOptions) {
+    this.graphqlType = type;
+    this.dataSource = dataSource;
+    this.args = options?.args;
+    this.requestMappingTemplate = options?.requestMappingTemplate;
+    this.responseMappingTemplate = options?.responseMappingTemplate;
+  }
+
+  /**
+   * Generate the string of this resolvable field
+   */
+  public toString(): string{
+    return this.graphqlType.toString();
+  }
+
+  /**
+   * Generate the args string of this resolvable field
+   */
+  public argsToString(): string{
+    let args = '( ';
+    Object.keys(this.args ?? {}).forEach((key) => {
+      const type = this.args?.[key].toString();
+      args = `${args}${key}: ${type} `;
+    });
+    return `${args})`;
+  }
+}
+
+/**
+ * Enum containing the Types that can be used to define ObjectTypes
+ */
+export enum Type {
+  /**
+   * `ID` scalar type is a unique identifier. `ID` type is serialized similar to `String`.
+   *
+   * Often used as a key for a cache and not intended to be human-readable.
+   */
+  ID = 'ID',
+  /**
+   * `String` scalar type is a free-form human-readable text.
+   */
+  STRING = 'String',
+  /**
+   * `Int` scalar type is a signed non-fractional numerical value.
+   */
+  INT = 'Int',
+  /**
+   * `Float` scalar type is a signed double-precision fractional value.
+   */
+  FLOAT = 'Float',
+  /**
+   * `Boolean` scalar type is a boolean value: true or false.
+   */
+  BOOLEAN = 'Boolean',
+
+  /**
+   * `AWSDate` scalar type represents a valid extended `ISO 8601 Date` string.
+   *
+   * In other words, accepts date strings in the form of `YYYY-MM-DD`. It accepts time zone offsets.
+   *
+   * @see https://en.wikipedia.org/wiki/ISO_8601#Calendar_dates
+   */
+  AWS_DATE = 'AWSDate',
+  /**
+   * `AWSTime` scalar type represents a valid extended `ISO 8601 Time` string.
+   *
+   * In other words, accepts date strings in the form of `hh:mm:ss.sss`. It accepts time zone offsets.
+   *
+   * @see https://en.wikipedia.org/wiki/ISO_8601#Times
+   */
+  AWS_TIME = 'AWSTime',
+  /**
+   * `AWSDateTime` scalar type represents a valid extended `ISO 8601 DateTime` string.
+   *
+   * In other words, accepts date strings in the form of `YYYY-MM-DDThh:mm:ss.sssZ`. It accepts time zone offsets.
+   *
+   * @see https://en.wikipedia.org/wiki/ISO_8601#Combined_date_and_time_representations
+   */
+  AWS_DATE_TIME = 'AWSDateTime',
+  /**
+   * `AWSTimestamp` scalar type represents the number of seconds since `1970-01-01T00:00Z`.
+   *
+   * Timestamps are serialized and deserialized as numbers.
+   */
+  AWS_TIMESTAMP = 'AWSTimestamp',
+  /**
+   * `AWSEmail` scalar type represents an email address string (i.e.`username@example.com`)
+   */
+  AWS_EMAIL = 'AWSEmail',
+  /**
+   * `AWSJson` scalar type represents a JSON string.
+   */
+  AWS_JSON = 'AWSJSON',
+  /**
+   * `AWSURL` scalar type represetns a valid URL string.
+   *
+   * URLs wihtout schemes or contain double slashes are considered invalid.
+   */
+  AWS_URL = 'AWSURL',
+  /**
+   * `AWSPhone` scalar type represents a valid phone number. Phone numbers maybe be whitespace delimited or hyphenated.
+   *
+   * The number can specify a country code at the beginning, but is not required for US phone numbers.
+   */
+  AWS_PHONE = 'AWSPhone',
+  /**
+   * `AWSIPAddress` scalar type respresents a valid `IPv4` of `IPv6` address string.
+   */
+  AWS_IP_ADDRESS = 'AWSIPAddress',
+
+  /**
+   * Type used for Object Types
+   */
+  OBJECT = 'OBJECT',
+}