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When executing the line Invoke-WebRequest -Uri https://www.freehaven.net/anonbib/date.html PowerShell throws WebCmdletResponseException. How can I get more information about it, and what may be causing this? While I can successfully get the contents of the page using Python, but in PowerShell it throws an exception.
Full exception:
Invoke-WebRequest : The underlying connection was closed: An unexpected error occurred on a send. At line:1 char:1 + Invoke-WebRequest -Uri https://www.freehaven.net/anonbib/date.html + ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + CategoryInfo : InvalidOperation: (System.Net.HttpWebRequest:HttpWebRequest) [Invoke-WebRequest], WebExc eption + FullyQualifiedErrorId : WebCmdletWebResponseException,Microsoft.PowerShell.Commands.InvokeWebRequestCommand
433
The Invoke-WebRequest cmdlet sends HTTP and HTTPS requests to a web page or web service. It parses the response and returns collections of links, images, and other significant HTML elements. This cmdlet was introduced in PowerShell 3.0.
Invoke-RestMethod - unlike Invoke-WebRequest - has deserialization built in: with a JSON response, it automatically parses the JSON text returned into a [pscustomobject] graph as if ConvertFrom-Json had been applied to it.
Invoke-WebRequest sends a request to the URI (Uniform Resource Identifier) which is also called Endpoint and retrieves the data from the Web Page. It directly works with the URL or with the REST API because some websites allow modifying the content using only APIs.
Invoke-WebRequest along with it's brother, Invite-RestMethod are the two PowerShell cmdlets you'll want to familiarize yourself with if you need to do any kind of web automation. The Invoke-WebRequest cmdlet is a part of the Microsoft. PowerShell. Utility module that comes with Windows PowerShell and PowerShell Core.
This is because Invoke-WebRequest uses HttpWebRequest under the hood, which in all but the most recent versions of .Net defaults to using SSLv3 and TLSv1.
You can see this by looking at the current value:
[System.Net.ServicePointManager]::SecurityProtocol
The site you're connecting to only supports TLS 1.2.
You can change the allowed protocols, but it applies globally during your application's run:
[System.Net.ServicePointManager]::SecurityProtocol = [System.Net.SecurityProtocolType]::Tls12
This overwrites the value.
Of course that would break anything else in your application which relies on a connection to a server that doesn't support TLS 1.2
A safe method might be to add TLS 1.2:
[System.Net.ServicePointManager]::SecurityProtocol] = (
[System.Net.ServicePointManager]::SecurityProtocol -bor
[System.Net.SecurityProtocolType]::Tls12
)
# parentheses are for readability
On the off-chance this still causes a problem for other sites (not sure what, maybe a site that says it accepts TLS 1.2 but its implementation is broken while its TLS 1.0 works fine?), you can save the previous value and restore it.
$cur = [System.Net.ServicePointManager]::SecurityProtocol]
try {
[System.Net.ServicePointManager]::SecurityProtocol = [System.Net.SecurityProtocolType]::Tls12
Invoke-WebRequest -Uri https://www.freehaven.net/anonbib/date.html
} finally {
[System.Net.ServicePointManager]::SecurityProtocol = $cur
}
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