Cassandra 的 Stargate 文档 API 的分页

Posted 2023-03-22

【中文标题】Cassandra 的 Stargate 文档 API 的分页

【英文标题】：Pagination of Stargate document API for Cassandra

【发布时间】：2021-11-12 14:07:45

【问题描述】：

Cassandra 的 Stargate 文档 API 提供页面大小以返回受页面大小限制的所有文档。页面大小的最大值为 20。如何获取下一个文档；即21到30？

Reading Documents using Stargate API for Cassandra

【参考方案1】：

因此，当您针对最初的 20 个运行查询时，您将在返回的 JSON 中获得一个名为 pageState。这是page-size=5 的示例：

% curl --request GET \
  --url https://$ASTRA_DB_ID-$ASTRA_DB_REGION.apps.astra.datastax.com/api/rest/v2/namespaces/$ASTRA_DB_KEYSPACE/collections/hello_docs\?page-size\=5 \
  -H "X-Cassandra-Token: $ASTRA_DB_APPLICATION_TOKEN" \
  -H 'Content-Type: application/json'
"pageState":"JGNlYjczMDc5LTE1NTItNGQyNS1hM2ExLWE2MzgxNWVlYTAyMADwf_____B_____","data":
"58b12778-0efd-466e-89bf-66a4c99adee1":"author":"Tom Clancy","title":"Red Rabbit",
"77fe8690-f8d4-43b8-b1c9-a328318d4eae":"author":"Tom Clancy","title":"Every Man a Tiger",
"3177f86c-a633-4302-92a5-de4c15ab5840":"author":"Tom Clancy","title":"Rainbow Six",
"cefc7117-fc73-47b8-a965-099cf3a59269":"author":"Tom Clancy","title":"Clear and Present Danger",
"ceb73079-1552-4d25-a3a1-a63815eea020":"author":"Tom Clancy","title":"The Cardinal of the Kremlin"%

当我想要获取接下来的 5 个文档时，我重新运行相同的查询，但将 page-state 参数与之前的结果返回的值一起添加：

&page-state\=JGNlYjczMDc5LTE1NTItNGQyNS1hM2ExLWE2MzgxNWVlYTAyMADwf_____B_____

当我将它添加到原始查询中时，它看起来像这样：

% curl --request GET \
--url https://$ASTRA_DB_ID-$ASTRA_DB_REGION.apps.astra.datastax.com/api/rest/v2/namespaces/$ASTRA_DB_KEYSPACE/collections/hello_docs\?page-size\=5\&page-state\=JGNlYjczMDc5LTE1NTItNGQyNS1hM2ExLWE2MzgxNWVlYTAyMADwf_____B_____ \
-H "X-Cassandra-Token: $ASTRA_DB_APPLICATION_TOKEN" \
-H 'Content-Type: application/json'

 "pageState":"JDUxMzVmMzFiLWY4NDYtNGZiNy1iNmFmLTk2YmU2OTMyNzlmMQDwf_____B_____","data":
"f42cc7d8-81ba-41d5-b5c9-c13f8d0009c6":"author":"Tom Clancy","title":"Patriot Games",
"46df315f-7208-4859-af1c-96c4953f70c7":"author":"Tom Clancy","title":"Without Remorse",
"b23af545-4fdc-4ac5-907a-7132d7429d26":"author":"Tom Clancy","title":"The Hunt for Red October",
"c6d55ecd-1631-4d5c-8320-d111662f8837":"other":"This is nonsensical stuff.","title":"Some Stuff",
"5135f31b-f846-4fb7-b6af-96be693279f1":"author":"Tom Clancy","title":"The Sum of all Fears"%

tl;dr;

添加结果中返回的pageState，你应该得到下一个20。

编辑 20211011

Stargate 文档已更新详细信息以解决此过程。

Retrieving all documents with Paging