Question

我刚刚开始学习GraphQL并做了一个简单的例子。我有这个架构

const {
    GraphQLObjectType,
    GraphQLString,
    GraphQLSchema,
    GraphQLID,
    // GraphQLInt,
    GraphQLList,
    GraphQLNonNull
} = graphql;

const ContinentType = new GraphQLObjectType({
    name: 'Continent',
    fields: () => ({
        id: {
            type: GraphQLID
        },
        details: {
            type: GraphQLString
        },
        name: {
            type: GraphQLString
        },
        country_to_show: {
            type: CountryType,
            resolve(parent, args) {
                console.log(parent);
                console.log(parent.countryID);
                return Country.findById(parent.countryID);
            }
        }
    })
});

const CountryType = new GraphQLObjectType({
    name: 'Country',
    fields: () => ({
        id: {
            type: GraphQLID
        },
        name: {
            type: GraphQLString
        },
        flag: {
            type: GraphQLString
        },
        countryCode: {
            type: GraphQLString
        },
        details: {
            type: GraphQLString
        }
    })
});

const RootQuery = new GraphQLObjectType({
    name: 'RootQueryType',
    fields: {

        continent: {
            type: ContinentType,
            args: {
                id: {
                    type: GraphQLID
                }
            },
            resolve(parent, args) {
                return Continent.findById(args.id);
            }
        },

        country: {
            type: CountryType,
            args: {
                id: {
                    type: GraphQLID
                }
            },
            resolve(parent, args) {
                return Country.findById(args.id);
            }
        },

        countrys: {
            type: new GraphQLList(CountryType),
            resolve(parent, args) {
                return Country.find({});
            }
        },

        contintens: {
            type: new GraphQLList(ContinentType),
            resolve(parent, args) {
                return Continent.find({});
            }
        },

    }

});

const Mutation = new GraphQLObjectType({
    name: 'Mutation',
    fields: {

        addContinent: {
            type: ContinentType,
            args: {
                name: {
                    type: new GraphQLNonNull(GraphQLString)
                },
                details: {
                    type: new GraphQLNonNull(GraphQLString)
                },
                countryID: {
                    type: new GraphQLNonNull(GraphQLList(GraphQLString))
                }
            },
            resolve(parent, args) {
                let continent = new Continent({
                    name: args.name,
                    details: args.details,
                    countryID: args.countryID
                });
                return continent.save();
            }
        },
        addCountry: {
            type: CountryType,
            args: {
                name: {
                    type: new GraphQLNonNull(GraphQLString)
                },
                details: {
                    type: new GraphQLNonNull(GraphQLString)
                },
                flag: {
                    type: new GraphQLNonNull(GraphQLString)
                },
                countryCode: {
                    type: new GraphQLNonNull(GraphQLString)
                },

            },
            resolve(parent, args) {
                let country = new Country({
                    name: args.name,
                    details: args.details,
                    countryCode: args.countryCode,
                    flag: args.flag
                });
                return country.save();
            }
        }
    }
});

module.exports = new GraphQLSchema({
    query: RootQuery,
    mutation: Mutation
});

当我尝试添加新的大陆时，我可以在数据库中看到记录已存储

{
    "_id": {
        "$oid": "5b60dea3ff0eba10ada3cbff"
    },
    "countryID": [
        "5b5cd39951017b08d3e1303a",
        "5b5cd3c77640c708edbcbf45"
    ],
    "name": "something",
    "details": "something",
    "__v": 0
}

但是在GrapiQL中执行addContinent突变后

mutation{
addContinent(name:"something",details:"something",countryID:["5b5cd39951017b08d3e1303a","5b5cd3c77640c708edbcbf45"]){
  name
  country_to_show{
    name
  }
}
}

我在country_to_show中看不到嵌套的嵌套结果，我在结果查询中只得到一个国家名称，而不是我保存的两个国家名称，所以不明白为什么？

{
  "data": {
    "addContinent": {
      "name": "something",
      "country_to_show": {
        "name": "albania"
      }
    }
  }
}

我认为这与以下事实有关：ContinentType中的country_to_show在数据库中搜索单个国家/地区，但是即使我尝试在结果查询中返回国家/地区列表，也无法找到解决方案运行突变后，我得到null。

Answer 1

您很近。这是一些应该起作用的修改后的代码：

INSERT

这将允许大洲和国家之间建立多对多关系。

GraphQL突变仅返回一个结果

1 个答案: