GoLang GraphQL 显示 EOF

Question

我正在尝试制作一个简单的 GO 服务器，运行使用 GraphQL 并与 PostgreSQL 连接，文件的编译和执行很顺利，与数据库的连接也很顺利，但是当我尝试为了检索数据库中的所有用户，我总是得到一个 EOF，查看我找到的答案

这个：

但是答案与我当前的项目不太吻合。

这是运行的所有文件。

DB.GO

package database

import (
    "database/sql"
    "fmt"
    "log"

    _ "github.com/lib/pq"
)

const (
    host     = "localhost"
    port     = 5432
    user     = "postgres"
    password = "lacb2208"
    dbname   = "IMOX_Tech_Personal"
)

var database *sql.DB

func init() {
    psqlInfo := fmt.Sprintf("host=%s port=%d user=%s "+
        "password=%s dbname=%s sslmode=disable",
        host, port, user, password, dbname)

    var err error
    database, err = sql.Open("postgres", psqlInfo)
    if err != nil {
        log.Fatal(err)
    }
}

type User struct {
    ID       int32  `json:"id"`
    UserName string `json:"username"`
}

// UserData is for params
type UserData struct {
    UserName string
}

func AllUsers(wrapper func(user *User)) {
    res, err := database.Query("SELECT id_user, username  FROM public.users")
    if err != nil {
        log.Println("error fetching all users", err)
    }
    defer res.Close()
    for res.Next() {
        user := User{}
        if err := res.Scan(&user.ID, &user.UserName); err != nil {
            log.Fatal(err)
        }
        wrapper(&user)
    }
}

RESOLVERS.GO

package resolvers

import (
    "../database"
)

type Resolver struct{}

type UserResolver struct {
    usr *database.User
}

// UserDataResolver is a struct for Resolver of the User params
type UserDataResolver struct {
    userData *database.UserData
}

func (r *Resolver) AllUsers() *[]*UserResolver {
    var users []*UserResolver
    wrapper := func(user *database.User) {
        users = append(users, &UserResolver{user})
    }

    database.AllUsers(wrapper)

    return &users
}

func (userR *UserResolver) ID() int32 {
    return userR.usr.ID
}

func (userR *UserResolver) UserName() string {
    return userR.usr.UserName
}

MAIN.GO

package main

import (
    "context"
    "fmt"
    "io/ioutil"
    "log"
    "net/http"
    "os"

    "github.com/gorilla/handlers"

    "github.com/gorilla/mux"

    "./resolvers"

    "github.com/graph-gophers/graphql-go"
    "github.com/graph-gophers/graphql-go/relay"
)

var (
    schema *graphql.Schema
)

const (
    schemaGraphQL         = "schema.graphqls"
    contentTypeKey        = "Content-Type"
    contentTypeJSONValue  = "application/json"
    authorizationTokenKey = "AuthorizationToken"
)

type (
    Authorization struct {
        Status             string `json:"status"`
        Message            string `json:"message"`
        AuthorizationToken string `json:"authorization_token`
    }
)

func init() {
    schemaFile, err := ioutil.ReadFile(schemaGraphQL)
    if err != nil {
        panic(err)
    }
    schema = graphql.MustParseSchema(string(schemaFile), &resolvers.Resolver{})
}

func main() {
    router := mux.NewRouter()
    router.HandleFunc("/", getToken)
    router.Handle("/graphiql", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
        w.Write(page)
    }))

    router.Handle("/query", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
        next := &relay.Handler{Schema: schema}
        // authorization := r.Header.Get(authorizationKey)
        // token := strings.Replace(authorization, "Bearer ", "", 1)
        token := "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJhZG1pbiI6dHJ1ZSwiaGFzaGVkLXBhc3N3b3JkIjoiZmMzZDBjMDAxMTdmZjFjY2FlOWQzMTAzZTU3M2M5YzMiLCJpc3MiOiJsdWNob25ldHZ2In0.o8D2I3UwZzxDCmdLHQiQ4XLBFcADOiPKgeuq_-32Nmk"
        ctx := context.WithValue(r.Context(), authorizationTokenKey, token)
        next.ServeHTTP(w, r.WithContext(ctx))
    }))

    fmt.Println("server is running on port 8989")
    server := http.ListenAndServe(":8989", handlers.LoggingHandler(os.Stdout, router))
    log.Fatal(server)
}

func getToken(response http.ResponseWriter, request *http.Request) {
    response.Header().Set(contentTypeKey, contentTypeJSONValue)
    response.WriteHeader(200)
}

var page = []byte(`
    <!DOCTYPE html>
    <html>
        <head>
            <link href="https://cdnjs.cloudflare.com/ajax/libs/graphiql/0.11.11/graphiql.min.css" rel="stylesheet" />
            <script src="https://cdnjs.cloudflare.com/ajax/libs/es6-promise/4.1.1/es6-promise.auto.min.js"></script>
            <script src="https://cdnjs.cloudflare.com/ajax/libs/fetch/2.0.3/fetch.min.js"></script>
            <script src="https://cdnjs.cloudflare.com/ajax/libs/react/16.2.0/umd/react.production.min.js"></script>
            <script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/16.2.0/umd/react-dom.production.min.js"></script>
            <script src="https://cdnjs.cloudflare.com/ajax/libs/graphiql/0.11.11/graphiql.min.js"></script>
        </head>
        <body style="width: 100%; height: 100%; margin: 0; overflow: hidden;">
            <div id="graphiql" style="height: 100vh;">Loading...</div>
            <script>
                function graphQLFetcher(graphQLParams) {
                    return fetch("/query", {
                        method: "post",
                        body: JSON.stringify(graphQLParams),
                        credentials: "include",
                    }).then(function (response) {
                        return response.text();
                    }).then(function (responseBody) {
                        try {
                            return JSON.parse(responseBody);
                        } catch (error) {
                            return responseBody;
                        }
                    });
                }
                ReactDOM.render(
                    React.createElement(GraphiQL, {fetcher: graphQLFetcher}),
                    document.getElementById("graphiql")
                );
            </script>
        </body>
    </html>
    `,
)

和SCHEMA.GRAPHQL

schema {
  query: Query
}

type User {
  id: Int!
  username: String!
}

input UserData {
  id: Int!
  userName: String!
}

type Query {
    allUsers: [User]
}

type Mutation {
    addUser(userData: UserData!): User
}

为什么 用户 table 来自 数据库:

CREATE TABLE public.users
(
  id_user integer NOT NULL DEFAULT nextval('users_id_user_seq'::regclass),
  username character varying(200) NOT NULL,
  password character varying(300) NOT NULL,
  hashed_password character varying(300) NOT NULL,
  status boolean NOT NULL DEFAULT true,
  CONSTRAINT users_pkey PRIMARY KEY (id_user),
  CONSTRAINT users_username_key UNIQUE (username)
)
WITH (
  OIDS=FALSE
);
ALTER TABLE public.users
  OWNER TO postgres;

当我运行 localhost:8989/query 时，我从服务器得到的唯一答案是 EOF 但是有没有 return 来自数据库的用户列表

谁能告诉我我的代码哪里做错了...

或者如何做一个好的查询:(

root@Crdzbird-Host:~/GoProjects/go-graphql-sample# curl -XPOST -d '{"query": "{ allUsers{} }"}' localhost:8989/query {"errors":[{"message":"Field \"allUsers\" of type \"[User]\" must have a selection of subfields. Did you mean \"allUsers { ... }\"?","locations":[{"line":1,"column":3}]}]}

Answer 1

一切都很好，我的问题是我想通过浏览器访问结果，但是当我在终端中输入时：

root@Crdzbird-Host:~/curl -X POST -H "Content-Type: application/json" -d '{"query": "{ allUsers {id,username} }"}' http://localhost:8989/query

我得到的值是：

{"data":{"allUsers":[{"id":1,"username":"Luis"},{"id":2,"username":"Jean"},{"id":3,"username":"Erich"},{"id":4,"username":"Marcos"},{"id":5,"username":"Alvin"},{"id":6,"username":"Jimmy"}]}}

我查询的方式不对，感谢大家的支持:)

GoLang GraphQL 显示 EOF

GoLang GraphQL display EOF

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