package main

import (
    "flag"
    "github.com/aws/aws-lambda-go/lambda"
    "github.com/aws/aws-sdk-go/aws"
    "github.com/aws/aws-sdk-go/aws/credentials"
    "github.com/aws/aws-sdk-go/aws/session"
    v4 "github.com/aws/aws-sdk-go/aws/signer/v4"
    "github.com/sony/appsync-client-go"
    "github.com/sony/appsync-client-go/graphql"
    "log"
)

type Response struct {
    Email  string `json:"email"`
    Id     int64  `json:"id"`
    Name   string `json:"name"`
    Phone  string `json:"phone"`
    Answer string `json:"answer"`
}

var (
    region = flag.String("region", "us-xxx-1", "AppSync API region")
    url    = flag.String("url", "https://xxx.appsync-api.us-xxx-1.amazonaws.com/graphql", "AppSync API URL")
    accessKeyID = "xxx"
    secretAccessKey = "xxx"

)

type Request struct {
    Id      int    `json:"id"`
    Message string `json:"message"`
}

func hello(arg Request) (Response, error) {
    query := `
        query MyQuery {
            getCustomers(id: 2) {
                email
                id
                name
                phone
            }
        }`

    credential := credentials.NewStaticCredentials(accessKeyID, secretAccessKey, "")
    conf := aws.NewConfig().WithRegion("us-east-1").WithCredentials(credential)

    sess := session.Must(session.NewSessionWithOptions(session.Options{Config: *conf}))
    signer := v4.NewSigner(sess.Config.Credentials)
    client := appsync.NewClient(appsync.NewGraphQLClient(graphql.NewClient(*url)),
        appsync.WithIAMAuthorization(*signer, *region, *url))
    response, err := client.Post(graphql.PostRequest{
        Query: query,
    })
    if err != nil {
        log.Fatal("error:", err)
        return Response{}, err
    }

    data := new(Response)
    if err := response.DataAs(data); err != nil {
        log.Fatalln("error:", err, response)
        return Response{}, err
    }
    log.Println(*data)
    return *data, nil

}

func main() {
    lambda.Start(hello)
    //hello()
}