我必须调用TeamCity公开的API，告诉我用户是否存在。 API网址是这样的：http://myteamcityserver.com:8080/httpAuth/app/rest/users/monkey
从浏览器（或fiddler）调用时，我得到以下内容：
Error has occurred during request processing (Not Found).
Error: jetbrains.buildServer.server.rest.errors.NotFoundException: No user can be found by username 'monkey'.
Could not find the entity requested. Check the reference is correct and the user has permissions to access the entity.
我必须使用powershell调用API。当我这样做时，我得到一个例外，我没有看到上面的文字。这是我使用的powershell：
try{
$client = New-Object System.Net.WebClient
$client.Credentials = New-Object System.Net.NetworkCredential $TeamCityAgentUserName, $TeamCityAgentPassword
$teamCityUser = $client.DownloadString($url)
return $teamCityUser
}
catch
{
$exceptionDetails = $_.Exception
Write-Host "$exceptionDetails" -foregroundcolor "red"
}
例外：
System.Management.Automation.MethodInvocationException: Exception calling "DownloadString" with "1" argument(s): "The remote server returned an error: (404) Not Found." ---> System.Net.WebException: The remote server returned an error: (404) Not Found.
at System.Net.WebClient.DownloadDataInternal(Uri address, WebRequest& request)
at System.Net.WebClient.DownloadString(Uri address)
at CallSite.Target(Closure , CallSite , Object , Object )
--- End of inner exception stack trace ---
at System.Management.Automation.ExceptionHandlingOps.CheckActionPreference(FunctionContext funcContext, Exception exception)
at System.Management.Automation.Interpreter.ActionCallInstruction`2.Run(InterpretedFrame frame)
at System.Management.Automation.Interpreter.EnterTryCatchFinallyInstruction.Run(InterpretedFrame frame)
at System.Management.Automation.Interpreter.EnterTryCatchFinallyInstruction.Run(InterpretedFrame frame)
我需要能够检查返回的页面是否包含上述文本。这样我知道是否应该自动创建新用户。我可以检查404，但我担心的是，如果API被更改并且呼叫确实返回404，那么我就不会更聪明了。
更改您的catch子句以捕获更具体的WebException，然后您可以使用它上面的Response属性来获取状态代码：
{
#...
}
catch [System.Net.WebException]
{
$statusCode = [int]$_.Exception.Response.StatusCode
$html = $_.Exception.Response.StatusDescription
}
BrokenGlass给出了答案，但这可能会有所帮助：
try
{
$URI='http://8bit-museum.de/notfound.htm'
$HTTP_Request = [System.Net.WebRequest]::Create($URI)
"check: $URI"
$HTTP_Response = $HTTP_Request.GetResponse()
# We then get the HTTP code as an integer.
$HTTP_Status = [int]$HTTP_Response.StatusCode
}
catch [System.Net.WebException]
{
$statusCode = [int]$_.Exception.Response.StatusCode
$statusCode
$html = $_.Exception.Response.StatusDescription
$html
}
$HTTP_Response.Close()
回复：检查：http://8bit-museum.de/notfound.htm 404 Not Found
另一种方法：
$URI='http://8bit-museum.de/notfound.htm'
try {
$HttpWebResponse = $null;
$HttpWebRequest = [System.Net.HttpWebRequest]::Create("$URI");
$HttpWebResponse = $HttpWebRequest.GetResponse();
if ($HttpWebResponse) {
Write-Host -Object $HttpWebResponse.StatusCode.value__;
Write-Host -Object $HttpWebResponse.GetResponseHeader("X-Detailed-Error");
}
}
catch {
$ErrorMessage = $Error[0].Exception.ErrorRecord.Exception.Message;
$Matched = ($ErrorMessage -match '[0-9]{3}')
if ($Matched) {
Write-Host -Object ('HTTP status code was {0} ({1})' -f $HttpStatusCode, $matches.0);
}
else {
Write-Host -Object $ErrorMessage;
}
$HttpWebResponse = $Error[0].Exception.InnerException.Response;
$HttpWebResponse.GetResponseHeader("X-Detailed-Error");
}
如果我理解了这个问题，那么$ ErrorMessage = $ Error [0] .Exception.ErrorRecord.Exception.Message包含你正在寻找的错误消息。 （来源：Error Handling in System.Net.HttpWebRequest::GetResponse()）
另一个简单的例子，希望这有助于：
BEGIN
{
# set an object to store results
$queries = New-Object System.Collections.ArrayList
Function Test-Website($Site)
{
try
{
# check the Site param passed in
$request = Invoke-WebRequest -Uri $Site
}
catch [System.Net.WebException] # web exception
{
# if a 404
if([int]$_.Exception.Response.StatusCode -eq 404)
{
$request = [PSCustomObject]@{Site=$site;ReturnCode=[int]$_.Exception.Response.StatusCode}
}
else
{
# set a variable to set a value available to automate with later
$request = [PSCustomObject]@{Site=$site;ReturnCode='another_thing'}
}
}
catch
{
# available to automate with later
$request = [PSCustomObject]@{Site=$site;ReturnCode='request_failure'}
}
# if successful as an invocation and has
# a StatusCode property
if($request.StatusCode)
{
$siteURI = $Site
$response = $request.StatusCode
}
else
{
$response = $request.ReturnCode
}
# return the data
return [PSCustomObject]@{Site=$Site;Response=$response}
}
}
PROCESS
{
# test all the things
$nullTest = Test-Website -Site 'http://www.Idontexist.meh'
$nonNullTest = Test-Website -Site 'https://www.stackoverflow.com'
$404Test = Test-Website -Site 'https://www.stackoverflow.com/thispagedoesnotexist'
# add all the things to results
$queries.Add($nullTest) | Out-Null
$queries.Add($nonNullTest) | Out-Null
$queries.Add($404Test) | Out-Null
# show the info
$queries | Format-Table
}
END{}
输出：
Site Response
---- --------
http://www.Idontexist.meh another_thing
https://www.stackoverflow.com 200
https://www.stackoverflow.com/thispagedoesnotexist 404
您可以尝试使用Internet Explorer COM对象。它允许您检查浏览器返回代码并导航HTML对象模型。
注意：我发现您需要从提升的PowerShell提示符运行此命令以维护COM对象定义。
$url = "http://myteamcityserver.com:8080/httpAuth/app/rest/users/monkey"
$ie = New-Object -ComObject InternetExplorer.Application
添加此项以查看浏览器
$ie.visibility = $true
导航到该站点
$ie.navigate($url)
这将暂停脚本，直到页面完全加载
do { start-sleep -Milliseconds 250 } until ($ie.ReadyState -eq 4)
然后验证您的URL以确保它不是错误页面
if ($ie.document.url -ne $url) {
Write-Host "Site Failed to Load" -ForegroundColor "RED"
} else {
[Retrieve and Return Data]
}
您可以通过$ ie.document导航HTML对象模型。使用Get-Member和HTML方法，如GetElementsByTagName（）或GetElementById（）。
如果凭据是一个问题，请将其构建到一个函数中，然后使用带有-Credentials参数的Invoke-Command来定义您的登录信息。