public async Task <ActionResult <IEnumerable <StockListItem> > > Get(
[FromQuery] string search,
[FromQuery] int?page,
[FromQuery] int?itemsPerPage)
{
if (((page == null ? 1 : 0) ^ (itemsPerPage == null ? 1 : 0)) != 0)
{
// page 或 itemsPerPage 没有同时提供
return(BadRequest());
}
var hbaseClient = _hbaseClientFactory.Create();
var scannerCreationOptions = new HBaseScannerCreationOptions
{
Batch = 1000,
MaxVersions = 1
};
// 获取所有的股票信息的列表
IEnumerable <StockListItem> stocksList = Array.Empty <StockListItem>();
using (var scanner = await hbaseClient.OpenScanner(RealtimeDataTableName, scannerCreationOptions))
{
while (await scanner.ReadNextBatch())
{
stocksList = stocksList.Concat(scanner.CurrentBatch.Select(StockListItem.FromHBaseRow));
}
}
// 在线程池线程中完成搜索和分页任务
stocksList = await Task.Run(() =>
{
if (!string.IsNullOrEmpty(search))
{
// 执行搜索
stocksList = stocksList.Where(
stock => stock.Code.IndexOf(search, StringComparison.CurrentCultureIgnoreCase) != -1 ||
stock.Name.IndexOf(search, StringComparison.CurrentCultureIgnoreCase) != -1);
}
if (page != null && itemsPerPage != null)
{
stocksList = stocksList.Skip(page.Value *itemsPerPage.Value).Take(itemsPerPage.Value);
}
return(stocksList);
});
return(new ActionResult <IEnumerable <StockListItem> >(stocksList));
}
/// <inheritdoc />
public async Task <IHBaseScanner> OpenScanner(string tableName, HBaseScannerCreationOptions options = null)
{
if (tableName == null)
{
throw new ArgumentNullException(nameof(tableName));
}
// 构造请求负载
var contentJson = string.Empty;
if (options != null)
{
contentJson = HBaseSerializationHelper.SerializeObject(options);
}
// 发送 HTTP 请求
var url = $"{tableName}/scanner";
var content = HttpRequestContentFactory.CreateJsonContent(contentJson);
HttpResponseMessage response;
using (var httpClient = CreateHttpClient())
{
response = await httpClient.PutAsync(url, content);
}
if (!response.IsSuccessStatusCode)
{
throw new HBaseException("HBase REST API 返回了表示错误的 HTTP 状态码：" + response.StatusCode);
}
// 从响应的 Location 头部拿到 Scanner 的接入点
if (!response.Headers.TryGetValues("Location", out var scannerEndpoints))
{
throw new HBaseException("HBase REST API 没有返回任何有效的 Scanner 终结点。");
}
var scannerEpt = scannerEndpoints.FirstOrDefault();
if (scannerEpt == null)
{
throw new HBaseException("HBase REST API 没有返回任何有效的 Scanner 终结点。");
}
return(new DefaultHBaseScanner(scannerEpt, _httpClientFactory));
}
