apollo 服务器 + 续集错误非空字段

Question

我正在运行一个apollo 服务器，并将sequelize 作为postgres 数据库的orm。这是架构：

    type Tag {

        id: ID!

        name: String!

    }

    type Service {

        id: ID!

        name: String!

        slug: String!

        tags: [Tag!]!

    }

解析器：

        findServicesByTag: async(_, { tag }, { models }) => {

            const res = await models.Service.findAll({

                where: {

                    '$Tags.name$': tag

                }

                ,include: [

                    {

                        model: models.Tag,

                        as: 'Tags'

                    }

                ]

            })

            console.log(res)

            return res

        }

但是当执行这个查询时

query {

  findServicesByTag(tag: "restaurant")

  {

    id name slug

    tags {

      name

    }

  }

}

我收到消息“无法为不可为空的字段 Service.id 返回 null”。

console.log 指令打印此数据：

[ Service {

    dataValues: { id: 1, name: 'Restaurant X', Tags: [Array] },

    _previousDataValues: { id: 1, name: 'Restaurant X', Tags: [Array] },

    _changed: Set {},

    _options:

     { isNewRecord: false,

       _schema: null,

       _schemaDelimiter: '',

       include: [Array],

       includeNames: [Array],

       includeMap: [Object],

       includeValidated: true,

       attributes: [Array],

       raw: true },

    isNewRecord: false,

    Tags: [ [Tag] ] },

  Service {

    dataValues: { id: 2, name: 'Restaurant Y', Tags: [Array] },

    _previousDataValues: { id: 2, name: 'Restaurant Y', Tags: [Array] },

    _changed: Set {},

    _options:

     { isNewRecord: false,

       _schema: null,

       _schemaDelimiter: '',

       include: [Array],

       includeNames: [Array],

       includeMap: [Object],

       includeValidated: true,

       attributes: [Array],

       raw: true },

    isNewRecord: false,

    Tags: [ [Tag] ] } ]

看起来 apollo 无法处理此数据，它不会查询后续标签实体。

Answer 1

您应该使用instance.get方法来获取dataValues。模型实例使用属性的概念进行操作dataValues，属性存储由实例表示的实际值。然后，您需要定义alias: 'tags'模型关联，因为 graphql 类型对象 -service具有tags字段。确保它们映射正确。"sequelize": "^5.21.3"使用和 的工作示例"apollo-server": "^2.19.0"。model.tsimport { sequelize } from '../../db';import { Model, DataTypes } from 'sequelize';class Service extends Model {}Service.init(  {    id: {      primaryKey: true,      type: DataTypes.INTEGER,      autoIncrement: true,      allowNull: false,    },    name: DataTypes.STRING,    slug: DataTypes.STRING,  },  { sequelize },);class Tag extends Model {}Tag.init(  {    id: {      primaryKey: true,      type: DataTypes.INTEGER,      autoIncrement: true,      allowNull: false,    },    name: DataTypes.STRING,  },  { sequelize },);Service.belongsToMany(Tag, { through: 'Service_Tag', as: 'tags' });Tag.belongsToMany(Service, { through: 'Service_Tag', as: 'services' });(async function test() {  try {    await sequelize.sync({ force: true });    //seed    await Service.bulkCreate(      [        { name: 'Restaurant X', slug: 'a', tags: [{ name: 'restaurant' }, { name: 'b' }] },        { name: 'Restaurant Y', slug: 'b', tags: [{ name: 'c' }] },        { name: 'Restaurant Z', slug: 'c', tags: [{ name: 'restaurant' }] },      ],      { include: [{ model: Tag, as: 'tags' }] },    );  } catch (error) {    console.log(error);  }})();export { Service, Tag };app.ts:import { ApolloServer, gql } from 'apollo-server';import * as models from './model';const typeDefs = gql`  type Tag {    id: ID!    name: String!  }  type Service {    id: ID!    name: String!    slug: String!    tags: [Tag!]!  }  type Query {    findServicesByTag(tag: String!): [Service]!  }`;const resolvers = {  Query: {    async findServicesByTag(_, { tag }, { models }) {      const res = await models.Service.findAll({        where: {          '$tags.name$': tag,        },        include: [          {            model: models.Tag,            as: 'tags',          },        ],      });      const data = res.map((v) => v.get({ plain: true }));      return data;    },  },};const server = new ApolloServer({  typeDefs,  resolvers,  context: {    models,  },});server.listen().then(({ url }) => {  console.log(`🚀  Server ready at ${url}`);});使用以下命令测试 GraphQl 查询curl： ⚡  curl 'http://localhost:4000/graphql' -H 'Accept-Encoding: gzip, deflate, br' -H 'Content-Type: application/json' -H 'Accept: application/json' -H 'Connection: keep-alive' -H 'Origin: chrome-extension://flnheeellpciglgpaodhkhmapeljopja' --data-binary '{"query":"\nquery{\n  findServicesByTag(tag: \"restaurant\"){\n    id\n    name\n    slug\n    tags {\n      \tname\n\t\t}\n  }\n}","variables":{}}' --compressed{"data":{"findServicesByTag":[{"id":"1","name":"Restaurant X","slug":"a","tags":[{"name":"restaurant"}]},{"id":"3","name":"Restaurant Z","slug":"c","tags":[{"name":"restaurant"}]}]}}数据库中的数据记录：node-sequelize-examples=# select * from "Service"; id |     name     | slug ----+--------------+------  1 | Restaurant X | a  2 | Restaurant Y | b  3 | Restaurant Z | c(3 rows)node-sequelize-examples=# select * from "Tag"; id |    name    ----+------------  1 | restaurant  2 | b  3 | c  4 | restaurant(4 rows)node-sequelize-examples=# select * from "Service_Tag"; ServiceId | TagId -----------+-------         1 |     1         1 |     2         2 |     3         3 |     4(4 rows)