如何在graphql中重用解析器

Question

我是 graphql 的新手，我正在使用 graphql 创建以下架构

// promotion type

const PromoType = new GraphQLObjectType({
  name: 'Promo',
  description: 'Promo object',
  fields: () => ({
    id: {
      type: GraphQLID,
      description: 'id of the promo'
    },
    title: {
      type: GraphQLString,
      description: 'this is just a test'
    },
    departments: {
      type: new GraphQLList(DepartmentType),
      description: 'departments associated with the promo'
    }
  })
})

部门类型

// department type

const DepartmentType = new GraphQLObjectType({
  name: 'Department',
  description: 'Department object',
  fields: () => ({
    id: {
      type: GraphQLID,
      description: 'id of the department'
    },
    name: {
      type: GraphQLString,
      description: 'name of the department'
    },
    createdAt: {
      type: GraphQLDate,
      description: 'date the promo is created'
    },
    updatedAt: {
      type: GraphQLDate,
      description: 'date the promo is last updated'
    }
  })
});

以下是解析器

// Promos resolver

const promos = {
  type: new GraphQLList(PromoType),
  resolve: (_, args, context) => {

    let promos = getPromos()
    let departments = getDepartmentsById(promos.promoId)
    return merge(promos, departments)
  }
};


//Departments resolver
const departments = {
  type: new GraphQLList(DepartmentType),
  args: {
      promoId: {
      type: GraphQLID
    }
  },
  resolve: (_, args, context) => {

    return getDepartmentsById(args.promoId)
  }
};

问题是我想使用部门的解析器进入促销的解析器来获取部门。

我可能遗漏了一些明显的东西，但有什么办法可以做到这一点？

Answer 1

这是实现它的方法。您想将其视为图形，而不仅仅是单个休息端点。

要获取Promo 的数据，您需要与我在此处的操作类似，但对于父节点，如果这有意义的话。所以，在例如查看者决定您添加查询Promo。

const PromoType = new GraphQLObjectType({
  name: 'Promo',
  description: 'Promo object',
  fields: () => ({
    id: {
      type: GraphQLID,
      description: 'id of the promo',
    },
    title: {
      type: GraphQLString,
      description: 'this is just a test',
    },
    departments: {
      type: new GraphQLList(DepartmentType),
      description: 'departments associated with the promo',
      resolve: (rootValue) => {
        return getDepartmentsById(rootValue.promoId);
      }
    }
  })
});