DevProxy not intercepting localhost requests when api is launched from Visual Studio 2022

[neil-thompson-schemeserve]

It's not clear to me how to get devProxy to intercept localhost requests when debug session launched from Visual Studio 2022 Pro. Requests made to https://jsonplaceholder.typicode.com are intercepted fine.

I have an asp net core web api that will launch on localhost:60309, and a sample ping endpoint

GET https://localhost:60309/ss/ping

I launch devproxy with a config file, which includes the port, an ExecutionSummaryPlugin and a reporter (all fine for jsonplaceholder.typicode.com)

"urlsToWatch": [
     "https://jsonplaceholder.typicode.com/*",
     "https://localhost:60309/*"
  ],

I've updated VS through the "Browse with..." dialog to Add a new browser,
FriendlyName: "EdgeProxy"
Program: "C:\Program Files (x86)\Microsoft\Edge\Application\msedge.exe"
Arguments: --proxy-bypass-list="<-loopback> --proxy-server="127.0.0.1:8000"`

I make sure no instance of edge is running. Click the Debug option in VS, choosing "EdgeProxy", which launches msedge with the API running - but devProxy never intercepts any requests to GET https://localhost:60309/ss/ping (made via a VSCode .http and from Postman)

Where am I going wrong?
I have tried variants of using the build in server. IISExpress, Debug, "Start without Debugging" - no variant has the proxy.

I have also tried just starting edge using Run: msedge --proxy-bypass-list="<-loopback> --proxy-server="127.0.0.1:8000
The choosing Edge as the browser in VS, which launches the app in a new tab of the browser launched from Run. Doesn't intercept.

Windows 11, all up to date. Any suggestions welcome.
A walkthrough would be amazing, if anyone else has got this to work.

[waldekmastykarz]

Thanks for reaching out and sorry to hear you're getting stuck. Could it be that Windows' proxy settings override Edge's proxy bypass list? If I recall correctly, you can also configure proxy bypass list in Windows' Internet settings.

[neil-thompson-schemeserve]

In Control Panel > Network and Internet > Internet Options
Connections tab > LAN Settings > Proxy Server> Advanced > Exceptions

I added localhost:60309, but this hasn't helped.
Also tried ticking "Bypass proxy server for local addresses" - no joy

Thanks though :)

[waldekmastykarz]

Thanks for confirming. We'll check it out and get back to you asap.

[waldekmastykarz]

I've followed your steps and it seems to be working just fine for me:

Here is my devproxyrc.json:

{
  "$schema": "https://raw.githubusercontent.com/dotnet/dev-proxy/main/schemas/v1.2.0/rc.schema.json",
  "plugins": [
    {
      "name": "GenericRandomErrorPlugin",
      "enabled": true,
      "pluginPath": "~appFolder/plugins/DevProxy.Plugins.dll",
      "configSection": "weatherApiErrors"
    }
  ],
  "urlsToWatch": [
    "https://localhost:7232/*"
  ],
  "weatherApiErrors": {
    "$schema": "https://raw.githubusercontent.com/dotnet/dev-proxy/main/schemas/v1.2.0/genericrandomerrorplugin.schema.json",
    "errorsFile": "weather-api-errors.json"
  }
}

And the weather-api-errors.json:

{
  "$schema": "https://raw.githubusercontent.com/dotnet/dev-proxy/main/schemas/v1.2.0/genericrandomerrorplugin.errorsfile.schema.json",
  "errors": [
    {
      "request": {
        "url": "https://localhost:7232/WeatherForecast*"
      },
      "responses": [
        {
          "statusCode": 500,
          "headers": [
            {
              "name": "content-type",
              "value": "application/json; charset=utf-8"
            }
          ],
          "body": {
            "type": "https://tools.ietf.org/html/rfc7231#section-6.6.1",
            "title": "An error occurred while processing your request.",
            "status": 500,
            "detail": "Internal server error - weather service temporarily unavailable"
          }
        },
        {
          "statusCode": 503,
          "headers": [
            {
              "name": "content-type",
              "value": "application/json; charset=utf-8"
            },
            {
              "name": "retry-after",
              "value": "30"
            }
          ],
          "body": {
            "type": "https://tools.ietf.org/html/rfc7231#section-6.6.4",
            "title": "Service Unavailable",
            "status": 503,
            "detail": "Weather service is temporarily overloaded. Please retry after 30 seconds."
          }
        },
        {
          "statusCode": 429,
          "headers": [
            {
              "name": "content-type",
              "value": "application/json; charset=utf-8"
            },
            {
              "name": "retry-after",
              "value": "60"
            }
          ],
          "body": {
            "type": "https://tools.ietf.org/html/rfc6585#section-4",
            "title": "Too Many Requests",
            "status": 429,
            "detail": "Rate limit exceeded. Please wait 60 seconds before making another request."
          }
        },
        {
          "statusCode": 502,
          "headers": [
            {
              "name": "content-type",
              "value": "application/json; charset=utf-8"
            }
          ],
          "body": {
            "type": "https://tools.ietf.org/html/rfc7231#section-6.6.3",
            "title": "Bad Gateway",
            "status": 502,
            "detail": "Unable to connect to weather data provider"
          }
        }
      ]
    }
  ]
}

The only thing I had to change was to fix quotes around arguments: --proxy-bypass-list="<-loopback>" --proxy-server="127.0.0.1:8000" (the closing quote behind loopback was missing)

[neil-thompson-schemeserve]

Thank you for trying that out!

I followed in your footsteps (one thing to clarify)

New asp.net core web api with weatherforecast
GET https://localhost:7253/WeatherForecast = 200
Copied your json files to my DevProxyConfigs folder (but changed the port to 7253)
devproxy --config-file D:\ss\DevProxyConfigs\devproxyrc.json
= comes up fine without errors or warnings.

info 1 error responses loaded from D:\ss\DevProxyConfigs\weathererrors.json
info Dev Proxy API listening on http://127.0.0.1:8897...
info Dev Proxy listening on 127.0.0.1:8000...

Can you describe your exact next steps please?

I have tried Run: msedge --proxy-bypass-list="<-loopback>" --proxy-server="127.0.0.1:8000" (sorry about the typo earlier, that was just a typo in the GH chat), then start a debug session (spawns new window), then copied url to msedge window opened with proxy args = nothing

and tried modifying the VS2022 Web Browser arguments to be the same ^^ but STILL nothing happens

I might be doing the wrong thing here, so looking to copy you as much as possible.

I have 2 VPNs, which were inactive, but I have closed the apps completely. No change.

Thank you!

EDIT: once I have your exact steps, if it still doesn't work I can try it on a different machine...