Node.js 如何将GraphQL连接到MySQL
我已经使用expresscli设置了一个简单的express项目,并按照教程创建了Node.js 如何将GraphQL连接到MySQL,node.js,graphql,Node.js,Graphql,我已经使用expresscli设置了一个简单的express项目,并按照教程创建了db.js和schema.js,但是在这一点上,我想不出如何调试这个错误/在graphiql文档中查看架构的任何部分 { "errors": [ { "message": "Schema must be an instance of GraphQLSchema. Also ensure that there are not multiple versions of GraphQL insta
db.js
和schema.js
,但是在这一点上,我想不出如何调试这个错误/在graphiql
文档中查看架构的任何部分
{
"errors": [
{
"message": "Schema must be an instance of GraphQLSchema. Also ensure that there are not multiple versions of GraphQL installed in your node_modules directory."
}
]
}
App.js
var express = require('express');
var path = require('path');
var favicon = require('serve-favicon');
var logger = require('morgan');
var cookieParser = require('cookie-parser');
var bodyParser = require('body-parser');
var index = require('./routes/index');
var users = require('./routes/users');
var schema = require('./schema');
var graphqlHTTP = require('express-graphql');
var app = express();
// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'pug');
// uncomment after placing your favicon in /public
//app.use(favicon(path.join(__dirname, 'public', 'favicon.ico')));
app.use(logger('dev'));
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({extended: false}));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));
app.use('/', index);
app.use('/users', users);
app.use('/api', graphqlHTTP({schema, graphiql: true}));
// catch 404 and forward to error handler
app.use(function(req, res, next) {
var err = new Error('Not Found');
err.status = 404;
next(err);
});
// error handler
app.use(function(err, req, res, next) {
// set locals, only providing error in development
res.locals.message = err.message;
res.locals.error = req.app.get('env') === 'development'
? err
: {};
// render the error page
res.status(err.status || 500);
res.render('error');
});
module.exports = app;
var Sequelize = require('sequelize');
var mysql = require('mysql');
var _ = require('lodash');
var Conn = new Sequelize('DB', 'Username', 'password', {
host: 'DB IP',
dialect: 'mysql'
});
var Sectors = Conn.define('sectors', {
name: {
type: Sequelize.STRING,
allowNull: false
}
});
Sectors.sync({force: true}).then(function () {
// Table created
return Sectors.create({
name: 'test'
});
});
exports.default = Conn;
var {
GraphQLSchema,
GraphQLObjectType,
GraphQLID,
GraphQLString,
GraphQLInt,
GraphQLBoolean,
GraphQLList,
GraphQLNonNull
} = require('graphql');
var Db = require('./db');
var Sectors = new GraphQLObjectType({
name: 'sectors',
description: 'list of all the sectors',
fields: () => {
return {
id: {
type: GraphQLInt,
resolve (sectors) {
return sectors.id;
}
},
name: {
type: GraphQLString,
resolve (sectors) {
return sectors.name;
}
}
};
}
});
var Query = new GraphQLObjectType({
name: 'Query',
description: 'Root query object',
fields: () => {
return {
sectors: {
type: new GraphQLList(Sectors),
args: {
id: {
type: GraphQLInt
},
name: {
type: GraphQLString
}
},
resolve (root, args) {
return Db.models.sectors.findAll({ where: args });
}
}
};
}
});
var Schema = new GraphQLSchema({query: Query});
exports.default = Schema;
db.js
var express = require('express');
var path = require('path');
var favicon = require('serve-favicon');
var logger = require('morgan');
var cookieParser = require('cookie-parser');
var bodyParser = require('body-parser');
var index = require('./routes/index');
var users = require('./routes/users');
var schema = require('./schema');
var graphqlHTTP = require('express-graphql');
var app = express();
// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'pug');
// uncomment after placing your favicon in /public
//app.use(favicon(path.join(__dirname, 'public', 'favicon.ico')));
app.use(logger('dev'));
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({extended: false}));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));
app.use('/', index);
app.use('/users', users);
app.use('/api', graphqlHTTP({schema, graphiql: true}));
// catch 404 and forward to error handler
app.use(function(req, res, next) {
var err = new Error('Not Found');
err.status = 404;
next(err);
});
// error handler
app.use(function(err, req, res, next) {
// set locals, only providing error in development
res.locals.message = err.message;
res.locals.error = req.app.get('env') === 'development'
? err
: {};
// render the error page
res.status(err.status || 500);
res.render('error');
});
module.exports = app;
var Sequelize = require('sequelize');
var mysql = require('mysql');
var _ = require('lodash');
var Conn = new Sequelize('DB', 'Username', 'password', {
host: 'DB IP',
dialect: 'mysql'
});
var Sectors = Conn.define('sectors', {
name: {
type: Sequelize.STRING,
allowNull: false
}
});
Sectors.sync({force: true}).then(function () {
// Table created
return Sectors.create({
name: 'test'
});
});
exports.default = Conn;
var {
GraphQLSchema,
GraphQLObjectType,
GraphQLID,
GraphQLString,
GraphQLInt,
GraphQLBoolean,
GraphQLList,
GraphQLNonNull
} = require('graphql');
var Db = require('./db');
var Sectors = new GraphQLObjectType({
name: 'sectors',
description: 'list of all the sectors',
fields: () => {
return {
id: {
type: GraphQLInt,
resolve (sectors) {
return sectors.id;
}
},
name: {
type: GraphQLString,
resolve (sectors) {
return sectors.name;
}
}
};
}
});
var Query = new GraphQLObjectType({
name: 'Query',
description: 'Root query object',
fields: () => {
return {
sectors: {
type: new GraphQLList(Sectors),
args: {
id: {
type: GraphQLInt
},
name: {
type: GraphQLString
}
},
resolve (root, args) {
return Db.models.sectors.findAll({ where: args });
}
}
};
}
});
var Schema = new GraphQLSchema({query: Query});
exports.default = Schema;
Schema.js
var express = require('express');
var path = require('path');
var favicon = require('serve-favicon');
var logger = require('morgan');
var cookieParser = require('cookie-parser');
var bodyParser = require('body-parser');
var index = require('./routes/index');
var users = require('./routes/users');
var schema = require('./schema');
var graphqlHTTP = require('express-graphql');
var app = express();
// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'pug');
// uncomment after placing your favicon in /public
//app.use(favicon(path.join(__dirname, 'public', 'favicon.ico')));
app.use(logger('dev'));
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({extended: false}));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));
app.use('/', index);
app.use('/users', users);
app.use('/api', graphqlHTTP({schema, graphiql: true}));
// catch 404 and forward to error handler
app.use(function(req, res, next) {
var err = new Error('Not Found');
err.status = 404;
next(err);
});
// error handler
app.use(function(err, req, res, next) {
// set locals, only providing error in development
res.locals.message = err.message;
res.locals.error = req.app.get('env') === 'development'
? err
: {};
// render the error page
res.status(err.status || 500);
res.render('error');
});
module.exports = app;
var Sequelize = require('sequelize');
var mysql = require('mysql');
var _ = require('lodash');
var Conn = new Sequelize('DB', 'Username', 'password', {
host: 'DB IP',
dialect: 'mysql'
});
var Sectors = Conn.define('sectors', {
name: {
type: Sequelize.STRING,
allowNull: false
}
});
Sectors.sync({force: true}).then(function () {
// Table created
return Sectors.create({
name: 'test'
});
});
exports.default = Conn;
var {
GraphQLSchema,
GraphQLObjectType,
GraphQLID,
GraphQLString,
GraphQLInt,
GraphQLBoolean,
GraphQLList,
GraphQLNonNull
} = require('graphql');
var Db = require('./db');
var Sectors = new GraphQLObjectType({
name: 'sectors',
description: 'list of all the sectors',
fields: () => {
return {
id: {
type: GraphQLInt,
resolve (sectors) {
return sectors.id;
}
},
name: {
type: GraphQLString,
resolve (sectors) {
return sectors.name;
}
}
};
}
});
var Query = new GraphQLObjectType({
name: 'Query',
description: 'Root query object',
fields: () => {
return {
sectors: {
type: new GraphQLList(Sectors),
args: {
id: {
type: GraphQLInt
},
name: {
type: GraphQLString
}
},
resolve (root, args) {
return Db.models.sectors.findAll({ where: args });
}
}
};
}
});
var Schema = new GraphQLSchema({query: Query});
exports.default = Schema;
啊哈,原因是出口错了
exports.default = Schema
像这样
module.exports = Schema
您可能想到了
导出默认模式
或其他什么,并犯了一个错误,但改用module.exports=Schema
。导出时带有“s”,我在开始时也犯了同样的错误。
我建议更频繁地使用console.log()调试js文件您是否在node_模块中安装了多个版本的graphql。。。虽然我认为:)如果您还没有正确导出和导入模式,那么清除节点_模块并重新安装可能是值得的?节点模块不起作用,关于模式,我不知道我只是遵循了Lee Benson,除了我使用了vanilla Js和mysql。没有错误!你认为你可能需要安装graphql sequelize吗?我只是用这个问题作为一个关于如何为graphql连接MySQL的一页教程!谢谢