使用 graphq 将 object 添加到 mongodb model 内的 object 数组中

Question

我制作了一个 GraphQL API 来检索和操作 mongo 数据库中的数据。 此数据表示包含书籍列表的作者，如 Author.ts 中所示。

作者.ts：

import { Document, Model, model, Schema } from "mongoose";
import { Ibook } from "./book";

export interface Iauthor extends Document {
    name: String;
    books: Array<Ibook>;
  }
  
const AuthorSchema: Schema = new Schema({
    name: { type: String, required: true },
    books: { type: Array, required: true }
  });
  
export const Author: Model<Iauthor> = model('author', AuthorSchema);

Book.ts：

import {Document, Model, model, Schema} from "mongoose";

export interface Ibook extends Document {
    title: String;
    pages: Number;
  }
  
const BookSchema: Schema = new Schema({
    title: { type: String, required: true },
    pages: { type: Number, required: true }
  });
  
export const Book: Model<Ibook> = model('book', BookSchema);

我正在使用查询解析器和突变解析器来读取和操作这些对象。 我只是迁移到 graphql-compose-mongoose 来生成解析器，而不是自己编程。 在遇到解析器“AssignBooktoAuthor”之前，我成功迁移了每个查询和突变。 这基本上是一个解析器，它将书籍 object 添加到作者书籍列表中。 我根本不知道如何让它与 graphql-compose-mongoose 一起工作。

作曲家.ts：

import { composeMongoose } from "graphql-compose-mongoose";
import { schemaComposer } from "graphql-compose";
import { Book } from "./models/book";
import { Author } from "./models/author";

const customizationOptions = {};
const BookTC = composeMongoose(Book, customizationOptions);
const AuthorTC = composeMongoose(Author, customizationOptions);

//in aparte file zetten prob
schemaComposer.Query.addFields({
  getAllBooks: BookTC.mongooseResolvers.findMany(),
  getBookById: BookTC.mongooseResolvers.findById(),
  getAllAuthors: AuthorTC.mongooseResolvers.findMany(),
  getAuthorById: AuthorTC.mongooseResolvers.findById(),
});

schemaComposer.Mutation.addFields({
  CreateBook: BookTC.mongooseResolvers.createOne(),
  UpdateBook: BookTC.mongooseResolvers.updateById(),
  DeleteBook: BookTC.mongooseResolvers.removeById(),
  CreateAuthor: AuthorTC.mongooseResolvers.createOne(),
  UpdateAuthor: AuthorTC.mongooseResolvers.updateById(),
  DeleteAuthor: AuthorTC.mongooseResolvers.removeById(),
  /**AssignBooktoAuthor: AuthorTC.mongooseResolvers.///What function does this??///**/
});

const graphqlSchema = schemaComposer.buildSchema();
export default graphqlSchema;

gql.ts（服务器文件）：

import { ApolloServer, gql } from "apollo-server-express";
import * as mongoose from "mongoose";
import * as express from "Express";
import * as dotenv from "dotenv";
import * as jwt from "jsonwebtoken";
import graphqlSchema from "./composer";

const app = express();
 
dotenv.config();

(async () => {
  mongoose.connect("mongodb+srv://xxxxxxx:xxxxxxx@clusterxxxxx.mongodb.net/myFirstDatabase?retryWrites=true&w=majority", { useUnifiedTopology: true , useNewUrlParser: true});

  const server = new ApolloServer({ 
    schema: graphqlSchema,
  });

  await server.start();

  //verifying token 
  app.use((req, res, next) => {
    const Token = req.header('auth-token');
    try{
      (Token && jwt.verify(Token, process.env.TOKEN_SECRET)) ? next() : console.log("mw: Unauthorized");
    }catch(err){
      console.log("mw:Unauthorized");
    }
  });

  server.applyMiddleware({ app });
  
  app.listen({ port: 4000 }, () =>
  console.log(`🚀 Server ready at http://localhost:4000${server.graphqlPath}`)
  );

})();

由于对 graphql-compose-mongoose 的支持不是很大，我希望有人可以帮助我解决这个问题！

Answer 1

我自己找到了解决方案！

Graphql 支持使用 object id 添加关系。 因此，在 model 中，您必须分配一个名为 authorid 的类型，然后添加一个带有 objectid 类型的“ref”。 例如，参见 book.ts。 有关 addrelation 示例，请参见 composer.ts。

Book.ts：

export interface Ibook extends Document {
  title: String;
  pages: Number;
  author: Schema.Types.ObjectId; 
}
  
const BookSchema: Schema = new Schema({
  title: { type: String, required: true },
  pages: { type: Number, required: true },
  author: { type: Schema.Types.ObjectId, ref:"author", required: true}
});

作曲家.ts：

BookTC.addRelation('author', {
  resolver: () => AuthorTC.mongooseResolvers.findById(),
  prepareArgs:{
    _id: source => source.author,
    skip: null,
    sort: null,    
  },
  projection: {author: true},
})

AuthorTC.addRelation('books', {
  resolver: () => BookTC.mongooseResolvers.findMany(),
  prepareArgs: {
    filter: source => ({ author: source._id }),
  },
  projection: { id: true },
});