我已经使用GraphQL了一段时间,并且能够成功启动一个简单的GraphQL Server . 现在我试图让它支持Relay,我的最终目标,并且我在添加对根节点查询和查看器查询的支持时遇到了麻烦 .
我理解节点和查看器的概念,但我没有按照我构建代码的方式工作 . 这是我的代码,组织成单独的文件:
./graphql/User/types.js
import {
GraphQLObjectType,
GraphQLInputObjectType,
GraphQLNonNull,
GraphQLID,
GraphQLList,
GraphQLString,
GraphQLInt,
GraphQLBoolean
} from 'graphql';
import { GraphQLLong } from '../scalars';
import { NodeInterface } from '../interfaces';
const fields = {
_id: {
type: new GraphQLNonNull(GraphQLID)
},
email: {
type: GraphQLString
},
firstName: {
type: GraphQLString
},
lastName: {
type: GraphQLString
},
jobTitle: {
type: GraphQLString
},
phone: {
type: GraphQLString
}
};
export const UserType = new GraphQLObjectType({
name: 'User',
description: 'User',
interface: NodeInterface,
fields: fields
})
./graphql/User/queries.js
import { GraphQLNonNull, GraphQLID, GraphQLList } from 'graphql';
import { UserType, UserInputType } from './types';
import UserModel from '../../models/User';
const User = {
type: UserType,
description: 'Get single user',
args: {
id: {
name: 'id',
type: new GraphQLNonNull(GraphQLID)
}
},
resolve(root, params) {
params.deleted = false;
return UserModel.find(params).exec();
}
}
const Users = {
type: new GraphQLList(UserType),
description: 'Get all users',
resolve(root) {
const companies = UserModel.find({ deleted: false }).exec();
if (!companies) {
throw new Error('Error getting users.')
}
return companies;
}
}
export default {
User,
Users
}
./graphql/Company/types.js
import {
GraphQLObjectType,
GraphQLInputObjectType,
GraphQLNonNull,
GraphQLID,
GraphQLList,
GraphQLString,
GraphQLInt,
GraphQLBoolean
} from 'graphql';
import { GraphQLLong } from '../scalars';
import { UserType } from '../User/types';
import { NodeInterface } from '../interfaces';
import UserModel from '../../models/User';
const fields = {
_id: {
type: new GraphQLNonNull(GraphQLID)
},
name: {
type: GraphQLString
},
ein: {
type: GraphQLString
},
users: {
type: new GraphQLList(UserType),
resolve(company) {
const { _id } = company;
return UserModel.find({ companyId: _id }).exec();
}
}
};
export const CompanyType = new GraphQLObjectType({
name: 'Company',
description: 'Company',
interface: NodeInterface,
fields: fields
})
./graphql/Company/queries.js
import { GraphQLNonNull, GraphQLID, GraphQLList } from 'graphql';
import { CompanyType, CompanyInputType } from './types';
import CompanyModel from '../../models/Company';
const Company = {
type: CompanyType,
description: 'Get single company',
args: {
id: {
name: 'id',
type: new GraphQLNonNull(GraphQLID)
}
},
resolve(root, params) {
params.deleted = false;
return CompanyModel.find(params).exec();
}
}
const Companies = {
type: new GraphQLList(CompanyType),
description: 'Get all companies',
resolve(root) {
const companies = CompanyModel.find({ deleted: false }).exec();
if (!companies) {
throw new Error('Error getting companies.')
}
return companies;
}
}
export default {
Company,
Companies
}
./graphql/interfaces.js
import {
GraphQLInterfaceType,
GraphQLNonNull,
GraphQLID
} from 'graphql';
const NodeInterface = new GraphQLInterfaceType({
name: 'Node',
fields: {
id: {
type: new GraphQLNonNull(GraphQLID)
}
},
resolveType: (source) => {
return source.__type;
}
});
export default NodeInterface;
./graphql/schema.js
import { GraphQLObjectType, GraphQLSchema } from 'graphql';
import queries from './queries';
import mutations from './mutations';
export default new GraphQLSchema({
query: new GraphQLObjectType({
name: 'Query',
fields: queries
}),
mutation: new GraphQLObjectType({
name: 'Mutation',
fields: mutations
})
});
./graphql/queries.js
import {
GraphQLObjectType,
GraphQLNonNull,
GraphQLID
} from 'graphql';
import { NodeInterface } from './interfaces';
import CompanyQueries from './Company/queries';
import UserQueries from './User/queries';
const RootQuery = new GraphQLObjectType({
name: 'RootQuery',
description: 'The root query',
fields: {
viewer: {
type: NodeInterface,
resolve(source, args, context) {
return { result: "VIEWER!" };
}
},
node: {
type: NodeInterface,
args: {
id: {
type: new GraphQLNonNull(GraphQLID)
}
},
resolve(source, args, context, info) {
return { result: "NODE QUERY" };
}
}
}
});
export default {
RootQuery,
...CompanyQueries,
...UserQueries
}
./server.js
import express from 'express';
import bodyParser from 'body-parser';
import mongoose from 'mongoose';
import morgan from 'morgan';
import graphqlHTTP from 'express-graphql';
import schema from './graphql/schema';
// set up example server
const app = express();
app.set('port', (process.env.API_PORT || 3001));
// logger
app.use(morgan('dev'));
// parse body
app.use(bodyParser.json());
app.use('/graphql', graphqlHTTP({
schema: schema,
graphiql: true,
pretty: true
}));
const mongoUri = process.env.MONGO_URI || 'mongodb://localhost/testdb';
mongoose.set('debug', true);
mongoose.connect(mongoUri, {
useMongoClient: true,
});
export default app;
RootQuery没有添加到Schema . 实际上我收到了这个错误:
Error: Query.RootQuery field type must be Output Type but got: undefined.
从概念上讲,我不知道如何修复此代码:
a)我不知道如何将RootQuery添加到我的查询中,我不知道是否需要将其他查询保存到我的服务器(因为Relay基本上依赖于节点查询) .
b)我还不能看到我的RootQuery如何发现对象类型并将其返回到 return source.__type
. 我已经添加了那段代码,但我不知道给定类型将填充此字段的方式或位置 .
虽然我理解一点GraphQL,但我还没有关于如何构建Relay的基础知识需要root查询(不是谈论分页器,但是一旦我解决了这一点,这是我的下一步) .
帮助赞赏 .