如何在aws-amplify中的列表查询中的字段上按日期(createdAt)排序?

时间:2019-10-02 14:29:05

标签: amazon-web-services sorting graphql schema aws-amplify

type Test @model @key(fields: ["id", "createdAt"]) {
  id: ID!
  name: String
  createdAt: String!
}

此模型创建了查询:

getTest(createdAt: String!id: ID!): Test

listTests(
  createdAt: ModelStringKeyConditionInput
  filter: ModelTestFilterInput
  id: ID
  limit: Int
  nextToken: String
  sortDirection: ModelSortDirection
): ModelTestConnection

该方案应如何请求按日期排序的列表?

1 个答案:

答案 0 :(得分:1)

当@key指定多个字段时,第一个字段用作HASH键,随后的字段用作SORT键。

https://aws-amplify.github.io/docs/cli-toolchain/graphql#key

可以列出具有相同HASH键的已排序项目。例如,列出用户的所有评论:

type Comment
  @model
  @key(fields: ["userId", "createdAt"]) {
    userId: ID!
    createdAt: String!
    text: String
}

假设您使用的是AWS Amplify的GraphQL客户端,这将按用户列出所有注释,并按最新的顺序排列:

import { API, graphqlOperation } from 'aws-amplify';
import { listComments } from '@/graphql/queries';

export default async function listCommentsForUser(userId) {
  const queryParams = {
    userId,
    sortDirection: 'DESC',
  };

  const operation = graphqlOperation(listComments, queryParams);

  return API.graphql(operation);
}

要列出自指定日期以来的评论(最新的优先),请更改查询参数以包括范围查询:

const queryParams = {
    userId,
    sortDirection: 'DESC',
    createdAt: { gt: timestamp },
  };