【发布时间】：2018-08-01 19:02:52
【问题描述】：
我开始着手一个项目，将现有的 VB.net 网络表单应用程序集成到存储在 AWS 上的新数据中。我已经下载了一个 Athena SDK，它表明它可以完全做到这一点，但我无法让它工作。这是我到目前为止的模块：
Imports System
Imports System.Threading
Imports System.Threading.Tasks
Imports System.Collections.Generic
Imports Amazon
Imports Amazon.Athena
Imports Amazon.Athena.Model
Namespace athena_api
Class AthenaQuery
Private Const ATHENA_TEMP_PATH As String = "s3://xxxxxxxxxxx"
Private Const ATHENA_DB As String = "xxxxx"
Public Sub New()
Using client = New AmazonAthenaClient(Amazon.RegionEndpoint.USEast1)
Dim qContext As QueryExecutionContext = New QueryExecutionContext()
qContext.Database = ATHENA_DB
Dim resConf As ResultConfiguration = New ResultConfiguration()
resConf.OutputLocation = ATHENA_TEMP_PATH
Console.WriteLine("Created Athena Client")
run(client, qContext, resConf).Wait()
End Using
End Sub
Public Shared Async Function run(ByVal client As IAmazonAthena, ByVal qContext As QueryExecutionContext, ByVal resConf As ResultConfiguration) As Task
Dim qReq As StartQueryExecutionRequest = New StartQueryExecutionRequest() With {
.QueryString = "select count(*) from testTable",
.QueryExecutionContext = qContext,
.ResultConfiguration = resConf
}
Try
Dim qRes As StartQueryExecutionResponse = Await client.StartQueryExecutionAsync(qReq)
Dim items As List(Of Dictionary(Of String, String)) = Await getQueryExecution(client, qRes.QueryExecutionId)
For Each item In items
For Each pair As KeyValuePair(Of String, String) In item
Console.WriteLine("Col: {0}", pair.Key)
Console.WriteLine("Val: {0}", pair.Value)
Next
Next
Catch e As InvalidRequestException
Console.WriteLine("Run Error: {0}", e.Message)
End Try
End Function
Public Shared Async Function getQueryExecution(ByVal client As IAmazonAthena, ByVal id As String) As Task(Of List(Of Dictionary(Of String, String)))
Dim items As List(Of Dictionary(Of String, String)) = New List(Of Dictionary(Of String, String))()
Dim results As GetQueryExecutionResponse = Nothing
Dim q As QueryExecution = Nothing
Dim qReq As GetQueryExecutionRequest = New GetQueryExecutionRequest() With {
.QueryExecutionId = id
}
Do
Try
results = Await client.GetQueryExecutionAsync(qReq)
q = results.QueryExecution
Console.WriteLine("Status: {0}... {1}", q.Status.State, q.Status.StateChangeReason)
Await Task.Delay(5000)
Catch e As InvalidRequestException
Console.WriteLine("GetQueryExec Error: {0}", e.Message)
End Try
Loop While q.Status.State = "RUNNING" OrElse q.Status.State = "QUEUED"
Console.WriteLine("Data Scanned for {0}: {1} Bytes", id, q.Statistics.DataScannedInBytes)
Dim resReq As GetQueryResultsRequest = New GetQueryResultsRequest() With {
.QueryExecutionId = id,
.MaxResults = 10
}
Dim resResp As GetQueryResultsResponse = Nothing
Do
resResp = Await client.GetQueryResultsAsync(resReq)
For Each row As Row In resResp.ResultSet.Rows
Dim dict As Dictionary(Of String, String) = New Dictionary(Of String, String)()
For i = 0 To resResp.ResultSet.ResultSetMetadata.ColumnInfo.Count - 1
dict.Add(resResp.ResultSet.ResultSetMetadata.ColumnInfo(i).Name, row.Data(i).VarCharValue)
Next
items.Add(dict)
Next
If resResp.NextToken IsNot Nothing Then
resReq.NextToken = resResp.NextToken
End If
Loop While resResp.NextToken IsNot Nothing
Return items
End Function
End Class
End Namespace
运行时出现以下错误：
在 mscorlib.dll 中发生了“System.AggregateException”类型的未处理异常
我也不清楚这个 api 如何对 AWS 进行身份验证...没有请求密钥或令牌，因此看起来任何具有 S3 路径和 DB 名称的人都可以访问。
谢谢大家，这是我第一次尝试使用 AWS 进行项目，所以请多多包涵！
【问题讨论】：
-
假设您从桌面运行此程序，它通过您可能已设置的
defaultAWS 配置文件进行身份验证。如果您尚未设置它，您可能需要这样做，错误可能会消失。 -
我被告知有一个默认配置文件，但仍然收到错误。还有其他想法吗？这个 API 的文档似乎为零。
-
如果您有默认配置文件，那么您应该擅长凭据。我需要查看 AggregateException 的内部异常才能真正了解问题所在。
标签： .net amazon-web-services amazon-athena