I am trying to translate this apache rewrite rule into web.config rules but I can't get it to work.
Basically it checks the user agent and redirect the agent to the url provided
# allow social media crawlers to work by redirecting them to a server-rendered static version on the page
RewriteCond %{HTTP_USER_AGENT (facebookexternalhit/[09]|Twitterbot|Pinterest|Google.*snippet)
RewriteRule qs/(\d*)$ http://sitetocrawl.com/doc?id=$1 [P]
This is what I have so far. However, I can't figure out how to catch the url querystring parameter. Basically the text string after http://example.com/qs/parameter
<rule name="Social Rewrite" patternSyntax="ECMAScript" stopProcessing="true">
<match url="urltomatchpattern" ignoreCase="true" negate="false" />
<conditions logicalGrouping="MatchAny" trackAllCaptures="false">
<add input="{HTTP_USER_AGENT}" pattern="facebookexternalhit/[0-9]|Twitterbot|Pinterest|Google.*snippet" />
</conditions>
<action type="Redirect" url="http://sitetocrawl.com/doc?parameter" appendQueryString="true" redirectType="Found" />
</rule>
EDIT:
I tried with many variants of simpler rules, like redirect/rewrite when a specific user agent requests the site(in my case, the facebook crawler). But I can't even get those rules to work. I am debugging using the Facebook OG debugger
<rule name="Rule1" stopProcessing="true">
<match url=".*" />
<conditions>
<add input="{HTTP_USER_AGENT}" pattern="facebookexternalhit/1.1|Facebot" />
</conditions>
<action type="Redirect" url="new url here" />
</rule>