问题描述
在 apolly-server-lambda 应用程序中启动 Playground 时出现此错误:
Playground.tsx:289 SyntaxError: Unexpected end of JSON input
at JSON.parse (<anonymous>)
at index.js:40
该应用只有一个测试解析器。我使用 type-graphql 来定义架构:
@Resolver()
export class InviteResolver {
@Query(() => String)
hello() {
return 'test';
}
}
然后我用生成的模式配置了 apollo 服务器:
async function createHandler() {
const schema = await buildSchema({
resolvers: [InviteResolver]
});
const server = new ApolloServer({
schema,playground: {
endpoint: "/dev/graphql"
}
})
return server.createHandler({
cors: {
origin: '*',methods: '*',allowedHeaders: '*',credentials: true,},});
}
export const handler = async function(event: APIGatewayProxyEvent,context: LambdaContext,callback: APIGatewayProxyCallback) {
context.callbackWaitsForEmptyEventLoop = false;
return await createHandler()
.then(handler => handler(event,context,callback));
};
最后,我已经设置好了无服务器:
service: app
provider:
name: aws
runtime: nodejs12.x
region: us-east-1
apiGateway:
shouldStartNameWithService: true
functions:
graphql:
handler: src/app.handler
events:
- http:
path: /graphql
method: post
cors: true
- http:
path: /graphql
method: get
cors: true
plugins:
- serverless-dotenv-plugin
- serverless-plugin-typescript
- serverless-offline
正如您在配置中看到的,我使用无服务器离线进行开发,并从以下开始:
serverless offline start
而且好像启动成功了:
┌───────────────────────────────────────────────────────────────────────────┐
│ │
│ POST | http://localhost:3000/dev/graphql │
│ POST | http://localhost:3000/2015-03-31/functions/graphql/invocations │
│ GET | http://localhost:3000/dev/graphql │
│ POST | http://localhost:3000/2015-03-31/functions/graphql/invocations │
│ │
└───────────────────────────────────────────────────────────────────────────┘
我可以在 http://localhost:3000/dev/graphql
访问 Playground UI,但我立即开始在控制台中一遍又一遍地看到上面的错误。我看不到架构或文档选项卡(基本上所有轮询都失败了),并且没有查询到达该解析器。
你们觉得我的接线方式有什么问题吗?
解决方法
问题是我导出的是异步函数而不是常规函数。
对我有用的是:
const globalSchema = buildSchema({
resolvers: [InviteResolver]
});
async function getServer() {
const schema = await globalSchema;
return new ApolloServer({
schema,playground: {
endpoint: "/dev/graphql"
}
});
}
export function handler(event: any,ctx: any,callback: any) {
getServer()
.then(server => server.createHandler({
cors: {
origin: '*',methods: '*',allowedHeaders: '*',credentials: true,},}))
.then(handler => handler(event,ctx,callback))
}