Allows adding multiple instances of the same plugin. Closes #554 (#557)

Author: waldekmastykarz

dev-proxy-abstractions/BaseProxyPlugin.cs

@@ -1,6 +1,7 @@
 // Copyright (c) Microsoft Corporation.
 // Licensed under the MIT License.
 
+using System.CommandLine;
 using Microsoft.Extensions.Configuration;
 
 namespace Microsoft.DevProxy.Abstractions;
@@ -11,6 +12,9 @@ public abstract class BaseProxyPlugin : IProxyPlugin
     protected ILogger? _logger;
 
     public virtual string Name => throw new NotImplementedException();
+
+    public virtual Option[] GetOptions() => Array.Empty<Option>();
+
     public virtual void Register(IPluginEvents pluginEvents,
                          IProxyContext context,
                          ISet<UrlToWatch> urlsToWatch,

dev-proxy-abstractions/CommandLineExtensions.cs

@@ -0,0 +1,25 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT License.
+
+using System.CommandLine;
+using System.CommandLine.Parsing;
+
+namespace Microsoft.DevProxy.Abstractions;
+
+public static class CommandLineExtensions
+{
+    public static T? GetValueForOption<T>(this ParseResult parseResult, string optionName, Option[] options)
+    {
+        // we need to remove the leading - because CommandLine stores the option
+        // name without them
+        var option = options
+            .FirstOrDefault(o => o.Name == optionName.TrimStart('-'))
+            as Option<T>;
+        if (option is null)
+        {
+            throw new InvalidOperationException($"Could not find option with name {optionName} and value type {typeof(T).Name}");
+        }
+
+        return parseResult.GetValueForOption(option);
+    }
+}

dev-proxy-abstractions/IProxyPlugin.cs

@@ -1,13 +1,15 @@
 // Copyright (c) Microsoft Corporation.
 // Licensed under the MIT License.
 
+using System.CommandLine;
 using Microsoft.Extensions.Configuration;
 
 namespace Microsoft.DevProxy.Abstractions;
 
 public interface IProxyPlugin
 {
     string Name { get; }
+    Option[] GetOptions();
     void Register(IPluginEvents pluginEvents,
                   IProxyContext context,
                   ISet<UrlToWatch> urlsToWatch,

dev-proxy-abstractions/PluginEvents.cs

@@ -57,7 +57,7 @@ public ThrottlingInfo(int throttleForSeconds, string retryAfterHeaderName)
 }
 
 public class ProxyHttpEventArgsBase
-{    
+{
     internal ProxyHttpEventArgsBase(SessionEventArgs session)
     {
         Session = session ?? throw new ArgumentNullException(nameof(session));
@@ -98,21 +98,21 @@ public ProxyResponseArgs(SessionEventArgs session, ResponseState responseState)
 
 public class InitArgs
 {
-    public InitArgs(RootCommand rootCommand)
+    public InitArgs()
     {
-        RootCommand = rootCommand ?? throw new ArgumentNullException(nameof(rootCommand));
     }
-    public RootCommand RootCommand { get; set; }
-
 }
 
 public class OptionsLoadedArgs
 {
-    public OptionsLoadedArgs(InvocationContext context)
+    public InvocationContext Context { get; set; }
+    public Option[] Options { get; set; }
+
+    public OptionsLoadedArgs(InvocationContext context, Option[] options)
     {
         Context = context ?? throw new ArgumentNullException(nameof(context));
+        Options = options ?? throw new ArgumentNullException(nameof(options));
     }
-    public InvocationContext Context { get; set; }
 }
 
 public class RequestLog

dev-proxy-plugins/MockResponses/MockResponsePlugin.cs

@@ -35,26 +35,30 @@ public class MockResponsePlugin : BaseProxyPlugin
 {
     protected MockResponseConfiguration _configuration = new();
     private MockResponsesLoader? _loader = null;
-    private readonly Option<bool?> _noMocks;
-    private readonly Option<string?> _mocksFile;
+    private static readonly string _noMocksOptionName = "--no-mocks";
+    private static readonly string _mocksFileOptionName = "--mocks-file";
     public override string Name => nameof(MockResponsePlugin);
     private IProxyConfiguration? _proxyConfiguration;
     // tracks the number of times a mock has been applied
     // used in combination with mocks that have an Nth property
     private Dictionary<string, int> _appliedMocks = new();
 
-    public MockResponsePlugin()
+    public override Option[] GetOptions()
     {
-        _noMocks = new Option<bool?>("--no-mocks", "Disable loading mock requests");
+        var _noMocks = new Option<bool?>(_noMocksOptionName, "Disable loading mock requests")
+        {
+            ArgumentHelpName = "no mocks"
+        };
         _noMocks.AddAlias("-n");
-        _noMocks.ArgumentHelpName = "no mocks";
 
-        _mocksFile = new Option<string?>("--mocks-file", "Provide a file populated with mock responses")
+        var _mocksFile = new Option<string?>(_mocksFileOptionName, "Provide a file populated with mock responses")
         {
             ArgumentHelpName = "mocks file"
         };
-    }
 
+        return [_noMocks, _mocksFile];
+    }
+    
     public override void Register(IPluginEvents pluginEvents,
                             IProxyContext context,
                             ISet<UrlToWatch> urlsToWatch,
@@ -65,25 +69,18 @@ public override void Register(IPluginEvents pluginEvents,
         configSection?.Bind(_configuration);
         _loader = new MockResponsesLoader(_logger!, _configuration);
 
-        pluginEvents.Init += OnInit;
         pluginEvents.OptionsLoaded += OnOptionsLoaded;
         pluginEvents.BeforeRequest += OnRequest;
 
         _proxyConfiguration = context.Configuration;
     }
 
-    private void OnInit(object? sender, InitArgs e)
-    {
-        e.RootCommand.AddOption(_noMocks);
-        e.RootCommand.AddOption(_mocksFile);
-    }
-
     private void OnOptionsLoaded(object? sender, OptionsLoadedArgs e)
     {
         InvocationContext context = e.Context;
-
+        
         // allow disabling of mocks as a command line option
-        var noMocks = context.ParseResult.GetValueForOption(_noMocks);
+        var noMocks = context.ParseResult.GetValueForOption<bool?>(_noMocksOptionName, e.Options);
         if (noMocks.HasValue)
         {
             _configuration.NoMocks = noMocks.Value;
@@ -95,7 +92,7 @@ private void OnOptionsLoaded(object? sender, OptionsLoadedArgs e)
         }
 
         // update the name of the mocks file to load from if supplied
-        string? mocksFile = context.ParseResult.GetValueForOption(_mocksFile);
+        var mocksFile = context.ParseResult.GetValueForOption<string?>(_mocksFileOptionName, e.Options);
         if (mocksFile is not null)
         {
             _configuration.MocksFile = Path.GetFullPath(ProxyUtils.ReplacePathTokens(mocksFile));

dev-proxy-plugins/RandomErrors/GraphRandomErrorPlugin.cs

@@ -28,7 +28,7 @@ public class GraphRandomErrorConfiguration
 
 public class GraphRandomErrorPlugin : BaseProxyPlugin
 {
-    private readonly Option<IEnumerable<int>> _allowedErrors;
+    private static readonly string _allowedErrorsOptionName = "--allowed-errors";
     private readonly GraphRandomErrorConfiguration _configuration = new();
     private IProxyConfiguration? _proxyConfiguration;
 
@@ -90,11 +90,6 @@ public class GraphRandomErrorPlugin : BaseProxyPlugin
 
     public GraphRandomErrorPlugin()
     {
-        _allowedErrors = new Option<IEnumerable<int>>("--allowed-errors", "List of errors that Dev Proxy may produce");
-        _allowedErrors.AddAlias("-a");
-        _allowedErrors.ArgumentHelpName = "allowed errors";
-        _allowedErrors.AllowMultipleArgumentsPerToken = true;
-
         _random = new Random();
     }
 
@@ -225,6 +220,18 @@ private void UpdateProxyBatchResponse(ProxyRequestArgs ev, GraphBatchResponsePay
 
     private static string BuildApiErrorMessage(Request r) => $"Some error was generated by the proxy. {(ProxyUtils.IsGraphRequest(r) ? ProxyUtils.IsSdkRequest(r) ? "" : String.Join(' ', MessageUtils.BuildUseSdkForErrorsMessage(r)) : "")}";
 
+    public override Option[] GetOptions()
+    {
+        var _allowedErrors = new Option<IEnumerable<int>>(_allowedErrorsOptionName, "List of errors that Dev Proxy may produce")
+        {
+            ArgumentHelpName = "allowed errors",
+            AllowMultipleArgumentsPerToken = true
+        };
+        _allowedErrors.AddAlias("-a");
+
+        return [_allowedErrors];
+    }
+
     public override void Register(IPluginEvents pluginEvents,
                          IProxyContext context,
                          ISet<UrlToWatch> urlsToWatch,
@@ -233,7 +240,6 @@ public override void Register(IPluginEvents pluginEvents,
         base.Register(pluginEvents, context, urlsToWatch, configSection);
 
         configSection?.Bind(_configuration);
-        pluginEvents.Init += OnInit;
         pluginEvents.OptionsLoaded += OnOptionsLoaded;
         pluginEvents.BeforeRequest += OnRequest;
 
@@ -244,17 +250,12 @@ public override void Register(IPluginEvents pluginEvents,
         _proxyConfiguration = context.Configuration;
     }
 
-    private void OnInit(object? sender, InitArgs e)
-    {
-        e.RootCommand.AddOption(_allowedErrors);
-    }
-
     private void OnOptionsLoaded(object? sender, OptionsLoadedArgs e)
     {
         InvocationContext context = e.Context;
 
         // Configure the allowed errors
-        IEnumerable<int>? allowedErrors = context.ParseResult.GetValueForOption(_allowedErrors);
+        var allowedErrors = context.ParseResult.GetValueForOption<IEnumerable<int>?>(_allowedErrorsOptionName, e.Options);
         if (allowedErrors?.Any() ?? false)
             _configuration.AllowedErrors = allowedErrors.ToList();
 

dev-proxy-plugins/RequestLogs/ExecutionSummaryPlugin.cs

@@ -27,16 +27,18 @@ public class ExecutionSummaryPlugin : BaseProxyPlugin
 {
     public override string Name => nameof(ExecutionSummaryPlugin);
     private ExecutionSummaryPluginConfiguration _configuration = new();
-    private readonly Option<string?> _filePath;
-    private readonly Option<SummaryGroupBy?> _groupBy;
+    private static readonly string _filePathOptionName = "--summary-file-path";
+    private static readonly string _groupByOptionName = "--summary-group-by";
     private const string _requestsInterceptedMessage = "Requests intercepted";
     private const string _requestsPassedThroughMessage = "Requests passed through";
 
-    public ExecutionSummaryPlugin()
+    public override Option[] GetOptions()
     {
-        _filePath = new Option<string?>("--summary-file-path", "Path to the file where the summary should be saved. If not specified, the summary will be printed to the console. Path can be absolute or relative to the current working directory.");
-        _filePath.ArgumentHelpName = "summary-file-path";
-        _filePath.AddValidator(input =>
+        var filePath = new Option<string?>(_filePathOptionName, "Path to the file where the summary should be saved. If not specified, the summary will be printed to the console. Path can be absolute or relative to the current working directory.")
+        {
+            ArgumentHelpName = "summary-file-path"
+        };
+        filePath.AddValidator(input =>
         {
             var outputFilePath = input.Tokens.First().Value;
             if (string.IsNullOrEmpty(outputFilePath))
@@ -58,15 +60,19 @@ public ExecutionSummaryPlugin()
             }
         });
 
-        _groupBy = new Option<SummaryGroupBy?>("--summary-group-by", "Specifies how the information should be grouped in the summary. Available options: `url` (default), `messageType`.");
-        _groupBy.ArgumentHelpName = "summary-group-by";
-        _groupBy.AddValidator(input =>
+        var groupBy = new Option<SummaryGroupBy?>(_groupByOptionName, "Specifies how the information should be grouped in the summary. Available options: `url` (default), `messageType`.")
+        {
+            ArgumentHelpName = "summary-group-by"
+        };
+        groupBy.AddValidator(input =>
         {
             if (!Enum.TryParse<SummaryGroupBy>(input.Tokens.First().Value, true, out var groupBy))
             {
                 input.ErrorMessage = $"{input.Tokens.First().Value} is not a valid option to group by. Allowed values are: {string.Join(", ", Enum.GetNames(typeof(SummaryGroupBy)))}";
             }
         });
+
+        return [filePath, groupBy];
     }
 
     public override void Register(IPluginEvents pluginEvents,
@@ -78,28 +84,21 @@ public override void Register(IPluginEvents pluginEvents,
 
         configSection?.Bind(_configuration);
 
-        pluginEvents.Init += OnInit;
         pluginEvents.OptionsLoaded += OnOptionsLoaded;
         pluginEvents.AfterRecordingStop += AfterRecordingStop;
     }
 
-    private void OnInit(object? sender, InitArgs e)
-    {
-        e.RootCommand.AddOption(_filePath);
-        e.RootCommand.AddOption(_groupBy);
-    }
-
     private void OnOptionsLoaded(object? sender, OptionsLoadedArgs e)
     {
         InvocationContext context = e.Context;
 
-        var filePath = context.ParseResult.GetValueForOption(_filePath);
+        var filePath = context.ParseResult.GetValueForOption<string?>(_filePathOptionName, e.Options);
         if (filePath is not null)
         {
             _configuration.FilePath = filePath;
         }
 
-        var groupBy = context.ParseResult.GetValueForOption(_groupBy);
+        var groupBy = context.ParseResult.GetValueForOption<SummaryGroupBy?>(_groupByOptionName, e.Options);
         if (groupBy is not null)
         {
             _configuration.GroupBy = groupBy.Value;

dev-proxy-plugins/RequestLogs/MinimalPermissionsGuidancePlugin.cs

@@ -42,15 +42,15 @@ public class MinimalPermissionsGuidancePlugin : BaseProxyPlugin
 {
     public override string Name => nameof(MinimalPermissionsGuidancePlugin);
     private MinimalPermissionsGuidancePluginConfiguration _configuration = new();
-    private readonly Option<string?> _filePath;
+    private static readonly string _filePathOptionName = "--minimal-permissions-summary-file-path";
 
-    public MinimalPermissionsGuidancePlugin()
+    public override Option[] GetOptions()
     {
-        _filePath = new Option<string?>("--minimal-permissions-summary-file-path", "Path to the file where the permissions summary should be saved. If not specified, the summary will be printed to the console. Path can be absolute or relative to the current working directory.")
+        var filePath = new Option<string?>(_filePathOptionName, "Path to the file where the permissions summary should be saved. If not specified, the summary will be printed to the console. Path can be absolute or relative to the current working directory.")
         {
             ArgumentHelpName = "minimal-permissions-summary-file-path"
         };
-        _filePath.AddValidator(input =>
+        filePath.AddValidator(input =>
         {
             var outputFilePath = input.Tokens.First().Value;
             if (string.IsNullOrEmpty(outputFilePath))
@@ -71,6 +71,8 @@ public MinimalPermissionsGuidancePlugin()
                 input.ErrorMessage = $"The directory {outputDir} does not exist.";
             }
         });
+
+        return [filePath];
     }
 
     public override void Register(IPluginEvents pluginEvents,
@@ -82,7 +84,6 @@ public override void Register(IPluginEvents pluginEvents,
 
         configSection?.Bind(_configuration);
 
-        pluginEvents.Init += Init;
         pluginEvents.OptionsLoaded += OptionsLoaded;
         pluginEvents.AfterRecordingStop += AfterRecordingStop;
     }
@@ -91,18 +92,13 @@ private void OptionsLoaded(object? sender, OptionsLoadedArgs e)
     {
         InvocationContext context = e.Context;
 
-        var filePath = context.ParseResult.GetValueForOption(_filePath);
+        var filePath = context.ParseResult.GetValueForOption<string?>(_filePathOptionName, e.Options);
         if (filePath is not null)
         {
             _configuration.FilePath = filePath;
         }
     }
 
-    private void Init(object? sender, InitArgs e)
-    {
-        e.RootCommand.AddOption(_filePath);
-    }
-
     private async Task AfterRecordingStop(object? sender, RecordingArgs e)
     {
         if (!e.RequestLogs.Any())

dev-proxy/Program.cs

@@ -39,11 +39,18 @@
 }
 
 PluginLoaderResult loaderResults = new PluginLoader(logger).LoadPlugins(pluginEvents, context);
-
-// have all the plugins init and provide any command line options
-pluginEvents.RaiseInit(new InitArgs(rootCommand));
-
-rootCommand.Handler = proxyHost.GetCommandHandler(pluginEvents, loaderResults.UrlsToWatch, logger);
+// have all the plugins init
+pluginEvents.RaiseInit(new InitArgs());
+
+var options = loaderResults.ProxyPlugins
+    .SelectMany(p => p.GetOptions())
+    // remove duplicates by comparing the option names
+    .GroupBy(o => o.Name)
+    .Select(g => g.First())
+    .ToList();
+options.ForEach(rootCommand.AddOption);
+
+rootCommand.Handler = proxyHost.GetCommandHandler(pluginEvents, options.ToArray(), loaderResults.UrlsToWatch, logger);
 
 // filter args to retrieve options
 var incomingOptions = args.Where(arg => arg.StartsWith("-")).ToArray();