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AWS::Serverless::GraphQLApi

使用 Amazon Serverless Application Model (Amazon SAM) AWS::Serverless::GraphQLApi 资源类型为您的无服务器应用程序创建和配置 Amazon AppSync GraphQL API。

若要了解 Amazon AppSync 的更多信息，请参阅《Amazon AppSync 开发人员指南》中的什么是 Amazon AppSync？。

语法

YAML

LogicalId:
  Type: AWS::Serverless::GraphQLApi
  Properties:
    ApiKeys: ApiKeys
    Auth: Auth
    Cache: AWS::AppSync::ApiCache
    DataSources: DataSource
    DomainName: AWS::AppSync::DomainName
    Functions: Function
    Logging: LogConfig
    Name: String
    Resolvers: Resolver
    SchemaInline: String
    SchemaUri: String
    Tags:
    - Tag
    XrayEnabled: Boolean

属性

示例

以 DynamoDB 为数据来源的 GraphQL API

在此示例中，我们创建了一个使用 DynamoDB 表作为数据来源的 GraphQL API。

schema.graphql

schema {
  query: Query
  mutation: Mutation
}

type Query {
  getPost(id: String!): Post
}

type Mutation {
  addPost(author: String!, title: String!, content: String!): Post!
}

type Post {
  id: String!
  author: String
  title: String
  content: String
  ups: Int!
  downs: Int!
  version: Int!
}

template.yaml

AWSTemplateFormatVersion: '2010-09-09'
Transform: AWS::Serverless-2016-10-31
...
Resources:
  DynamoDBPostsTable:
    Type: AWS::Serverless::SimpleTable

  MyGraphQLAPI:
    Type: AWS::Serverless::GraphQLApi
    Properties:
      SchemaUri: ./sam_graphql_api/schema.graphql
      Auth:
        Type: AWS_IAM
      DataSources:
        DynamoDb:
          PostsDataSource:
            TableName: !Ref DynamoDBPostsTable
            TableArn: !GetAtt DynamoDBPostsTable.Arn
      Functions:
        preprocessPostItem:
          Runtime:
            Name: APPSYNC_JS
            Version: 1.0.0
          DataSource: NONE
          CodeUri: ./sam_graphql_api/preprocessPostItem.js
        createPostItem:
          Runtime:
            Name: APPSYNC_JS
            Version: "1.0.0"
          DataSource: PostsDataSource
          CodeUri: ./sam_graphql_api/createPostItem.js
        getPostFromTable:
          Runtime:
            Name: APPSYNC_JS
            Version: "1.0.0"
          DataSource: PostsDataSource
          CodeUri: ./sam_graphql_api/getPostFromTable.js
      Resolvers:
        Mutation:
          addPost:
            Runtime:
              Name: APPSYNC_JS
              Version: "1.0.0"
            Pipeline:
            - preprocessPostItem
            - createPostItem
        Query:
          getPost:
            CodeUri: ./sam_graphql_api/getPost.js
            Runtime:
              Name: APPSYNC_JS
              Version: "1.0.0"
            Pipeline:
            - getPostFromTable

createPostItem.js

import { util } from "@aws-appsync/utils";

export function request(ctx) {
  const { key, values } = ctx.prev.result;
  return {
    operation: "PutItem",
    key: util.dynamodb.toMapValues(key),
    attributeValues: util.dynamodb.toMapValues(values),
  };
}

export function response(ctx) {
  return ctx.result;
}

getPostFromTable.js

import { util } from "@aws-appsync/utils";

export function request(ctx) {
  return dynamoDBGetItemRequest({ id: ctx.args.id });
}

export function response(ctx) {
  return ctx.result;
}

/**
 * A helper function to get a DynamoDB item
 */
function dynamoDBGetItemRequest(key) {
  return {
    operation: "GetItem",
    key: util.dynamodb.toMapValues(key),
  };
}

preprocessPostItem.js

import { util } from "@aws-appsync/utils";

export function request(ctx) {
  const id = util.autoId();
  const { ...values } = ctx.args;
  values.ups = 1;
  values.downs = 0;
  values.version = 1;
  return { payload: { key: { id }, values: values } };
}

export function response(ctx) {
  return ctx.result;
}

解析程序代码如下：

getPost.js

export function request(ctx) {
  return {};
}

export function response(ctx) {
  return ctx.prev.result;
}

以 Lambda 函数为数据来源的 GraphQL API

在此示例中，我们创建了一个使用 Lambda 函数作为数据来源的 GraphQL API。

template.yaml

AWSTemplateFormatVersion: '2010-09-09'
Transform: AWS::Serverless-2016-10-31
...
Resources:
  MyLambdaFunction:
    Type: AWS::Serverless::Function
    Properties:
      Handler: index.handler
      Runtime: nodejs14.x
      CodeUri: ./lambda

  MyGraphQLAPI:
    Type: AWS::Serverless::GraphQLApi
    Properties:
      Name: MyApi
      SchemaUri: ./gql/schema.gql
      Auth:
        Type: API_KEY
      ApiKeys:
        MyApiKey:
          Description: my api key
      DataSources:
        Lambda:
          MyLambdaDataSource:
            FunctionArn: !GetAtt MyLambdaFunction.Arn
      Functions:
        lambdaInvoker:
          Runtime:
            Name: APPSYNC_JS
            Version: 1.0.0
          DataSource: MyLambdaDataSource
          CodeUri: ./gql/invoker.js
      Resolvers:
        Mutation:
          addPost:
            Runtime:
              Name: APPSYNC_JS
              Version: 1.0.0
            Pipeline:
            - lambdaInvoker
        Query:
          getPost:
            Runtime:
              Name: APPSYNC_JS
              Version: 1.0.0
            Pipeline:
            - lambdaInvoker

Outputs:
  MyGraphQLAPI:
    Description: AppSync API
    Value: !GetAtt MyGraphQLAPI.GraphQLUrl
  MyGraphQLAPIMyApiKey:
    Description: API Key for authentication
    Value: !GetAtt MyGraphQLAPIMyApiKey.ApiKey

schema.graphql

schema {
  query: Query
  mutation: Mutation
}
type Query {
  getPost(id: ID!): Post
}
type Mutation {
  addPost(id: ID!, author: String!, title: String, content: String): Post!
}
type Post {
  id: ID!
  author: String!
  title: String
  content: String
  ups: Int
  downs: Int
}

函数如下：

lambda/index.js

exports.handler = async (event) => {
  console.log("Received event {}", JSON.stringify(event, 3));

  const posts = {
    1: {
      id: "1",
      title: "First book",
      author: "Author1",
      content: "Book 1 has this content",
      ups: "100",
      downs: "10",
    },
  };

  console.log("Got an Invoke Request.");
  let result;
  switch (event.field) {
    case "getPost":
      return posts[event.arguments.id];
    case "addPost":
      // return the arguments back
      return event.arguments;
    default:
      throw new Error("Unknown field, unable to resolve " + event.field);
  }
};

invoker.js

import { util } from "@aws-appsync/utils";

export function request(ctx) {
  const { source, args } = ctx;
  return {
    operation: "Invoke",
    payload: { field: ctx.info.fieldName, arguments: args, source },
  };
}

export function response(ctx) {
  return ctx.result;
}