Adds the --discover option. Closes #1038 (#1062)

Author: waldekmastykarz

dev-proxy/CommandHandlers/ProxyCommandHandler.cs

@@ -145,6 +145,11 @@ private void ParseOptions(InvocationContext context)
         {
             Configuration.TimeoutSeconds = timeout.Value;
         }
+        var isDiscover = context.ParseResult.GetValueForOption<bool?>(ProxyHost.DiscoverOptionName, _options);
+        if (isDiscover is not null)
+        {
+            Configuration.Record = true;
+        }
     }
 
     private async Task CheckForNewVersionAsync()

dev-proxy/PluginLoader.cs

@@ -14,7 +14,7 @@ internal class PluginLoaderResult(ISet<UrlToWatch> urlsToWatch, IEnumerable<IPro
     public IEnumerable<IProxyPlugin> ProxyPlugins { get; } = proxyPlugins ?? throw new ArgumentNullException(nameof(proxyPlugins));
 }
 
-internal class PluginLoader(ILogger logger, ILoggerFactory loggerFactory)
+internal class PluginLoader(bool isDiscover, ILogger logger, ILoggerFactory loggerFactory)
 {
     private PluginConfig? _pluginConfig;
     private readonly ILogger _logger = logger ?? throw new ArgumentNullException(nameof(logger));
@@ -126,7 +126,25 @@ private PluginConfig PluginConfig
             if (_pluginConfig == null)
             {
                 _pluginConfig = new PluginConfig();
-                Configuration.Bind(_pluginConfig);
+
+                if (isDiscover)
+                {
+                    _pluginConfig.Plugins.Add(new PluginReference
+                    {
+                        Name = "UrlDiscoveryPlugin",
+                        PluginPath = "~appFolder/plugins/dev-proxy-plugins.dll"
+                    });
+                    _pluginConfig.Plugins.Add(new PluginReference
+                    {
+                        Name = "PlainTextReporter",
+                        PluginPath = "~appFolder/plugins/dev-proxy-plugins.dll"
+                    });
+                    _pluginConfig.UrlsToWatch.Add("https://*/*");
+                }
+                else
+                {
+                    Configuration.Bind(_pluginConfig);
+                }
 
                 if (ProxyHost.UrlsToWatch is not null && ProxyHost.UrlsToWatch.Any())
                 {

dev-proxy/Program.cs

@@ -53,8 +53,14 @@
 var hasGlobalOption = args.Any(arg => globalOptions.Contains(arg));
 var hasHelpOption = args.Any(arg => helpOptions.Contains(arg));
 
+var isDiscover = args.Contains("--discover", StringComparer.OrdinalIgnoreCase);
+if (isDiscover)
+{
+    logger.LogWarning("Dev Proxy is running in URL discovery mode. Configured plugins and URLs to watch will be ignored.");
+}
+
 // load plugins to get their options and commands
-var pluginLoader = new PluginLoader(logger, loggerFactory);
+var pluginLoader = new PluginLoader(isDiscover, logger, loggerFactory);
 PluginLoaderResult loaderResults = await pluginLoader.LoadPluginsAsync(pluginEvents, context);
 var options = loaderResults.ProxyPlugins
     .SelectMany(p => p.GetOptions())

dev-proxy/ProxyHost.cs

@@ -37,6 +37,8 @@ internal class ProxyHost
     private static Option<IEnumerable<string>?>? _urlsToWatchOption;
     internal static readonly string TimeoutOptionName = "--timeout";
     private readonly Option<long?> _timeoutOption;
+    internal static readonly string DiscoverOptionName = "--discover";
+    private readonly Option<bool?> _discoverOption;
 
     private static bool _configFileResolved = false;
     private static string _configFile = "devproxyrc.json";
@@ -231,6 +233,7 @@ public ProxyHost()
         };
 
         _noFirstRunOption = new Option<bool?>(NoFirstRunOptionName, "Skip the first run experience");
+        _discoverOption = new Option<bool?>(DiscoverOptionName, "Run Dev Proxy in discovery mode");
 
         _asSystemProxyOption = new Option<bool?>(AsSystemProxyOptionName, "Set Dev Proxy as the system proxy");
         _asSystemProxyOption.AddValidator(input =>
@@ -314,7 +317,8 @@ public RootCommand GetRootCommand(ILogger logger)
             // _urlsToWatchOption is set while initialize the Program
             // As such, it's always set here
             _urlsToWatchOption!,
-            _timeoutOption
+            _timeoutOption,
+            _discoverOption
         };
         command.Description = "Dev Proxy is a command line tool for testing Microsoft Graph, SharePoint Online and any other HTTP APIs.";
 
@@ -487,6 +491,7 @@ public RootCommand GetRootCommand(ILogger logger)
             _asSystemProxyOption,
             _installCertOption,
             _timeoutOption,
+            _discoverOption,
             .. optionsFromPlugins,
         ],
         urlsToWatch,