Don't Throw Away All Those web.config Settings

ASP.NET Core might not use a complicated hierarchy of XML configuration files anymore, but if you host under IIS, then IIS and web.config are still the best of friends. There is some XML configuration required to run Core under IIS, specifically the part to reverse proxy all incoming requests over to the ASP.NET Core module and ultimately into the Kestrel server.

Other pieces of web.config still work in the new world of ASP.NET, too. For example, IIS will still honor rewrite rules in web.config.

Here is a sample web.config to enforce lower case URLs that also proxies to the ASP.NET Core Module.

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <system.webServer>

    <rewrite>
      <rules>
        <rule name="Convert to lower case" stopProcessing="true">
          <match url=".*[A-Z].*" ignoreCase="false" />
          <action type="Redirect" url="{ToLower:{R:0}}" redirectType="Permanent" />
        </rule>
      </rules>
    </rewrite>
    
    <handlers>
      <add name="aspNetCore" path="*" verb="*" 
           modules="AspNetCoreModule" resourceType="Unspecified"/>
    </handlers>
    
    <aspNetCore processPath="%LAUNCHER_PATH%" arguments="%LAUNCHER_ARGS%" 
                stdoutLogEnabled="false" stdoutLogFile=".\logs\stdout" 
                forwardWindowsAuthToken="false"/>
    
  </system.webServer>
</configuration>