mm + ...

src/WireMock.Net.Minimal/Matchers/Request/RequestMessageMultiPartMatcher.cs

@@ -12,7 +12,7 @@ namespace WireMock.Matchers.Request;
 /// </summary>
 public class RequestMessageMultiPartMatcher : IRequestMatcher
 {
-    private static readonly IMimeKitUtils MimeKitUtils = TypeLoader.LoadStaticInstance<IMimeKitUtils>();
+    private readonly IMimeKitUtils _mimeKitUtils = LoadMimeKitUtils();
 
     /// <summary>
     /// The matchers.
@@ -62,7 +62,7 @@ public class RequestMessageMultiPartMatcher : IRequestMatcher
             return requestMatchResult.AddScore(GetType(), score, null);
         }
 
-        if (!MimeKitUtils.TryGetMimeMessage(requestMessage, out var message))
+        if (!_mimeKitUtils.TryGetMimeMessage(requestMessage, out var message))
         {
             return requestMatchResult.AddScore(GetType(), score, null);
         }
@@ -96,4 +96,14 @@ public class RequestMessageMultiPartMatcher : IRequestMatcher
 
         return requestMatchResult.AddScore(GetType(), score, exception);
     }
+
+    private static IMimeKitUtils LoadMimeKitUtils()
+    {
+        if (TypeLoader.TryLoadStaticInstance<IMimeKitUtils>(out var mimeKitUtils))
+        {
+            return mimeKitUtils;
+        }
+
+        throw new InvalidOperationException("MimeKit is required for RequestMessageMultiPartMatcher. Please install the WireMock.Net.MimePart package.");
+    }
 }

src/WireMock.Net.Minimal/Owin/Mappers/OwinResponseMapper.cs

@@ -179,9 +179,12 @@ namespace WireMock.Owin.Mappers
                     return (bodyData.Encoding ?? _utf8NoBom).GetBytes(jsonBody);
 
                 case BodyType.ProtoBuf:
-                    var protoDefinitions = bodyData.ProtoDefinition?.Invoke().Texts;
-                    var protoBufUtils = TypeLoader.LoadStaticInstance<IProtoBufUtils>();
-                    return await protoBufUtils.GetProtoBufMessageWithHeaderAsync(protoDefinitions, bodyData.ProtoBufMessageType, bodyData.BodyAsJson).ConfigureAwait(false);
+                    if (TypeLoader.TryLoadStaticInstance<IProtoBufUtils>(out var protoBufUtils))
+                    {
+                        var protoDefinitions = bodyData.ProtoDefinition?.Invoke().Texts;
+                        return await protoBufUtils.GetProtoBufMessageWithHeaderAsync(protoDefinitions, bodyData.ProtoBufMessageType, bodyData.BodyAsJson).ConfigureAwait(false);
+                    }
+                    break;
 
                 case BodyType.Bytes:
                     return bodyData.BodyAsBytes;

src/WireMock.Net.Minimal/RequestMessage.cs

@@ -184,16 +184,9 @@ public class RequestMessage : IRequestMessage
 //#endif
 
 #if MIMEKIT
-        try
+        if (TypeLoader.TryLoadStaticInstance<IMimeKitUtils>(out var mimeKitUtils) && mimeKitUtils.TryGetMimeMessage(this, out var mimeMessage))
         {
-            if (TypeLoader.LoadStaticInstance<IMimeKitUtils>().TryGetMimeMessage(this, out var mimeMessage))
-            {
-                BodyAsMimeMessage = mimeMessage;
-            }
-        }
-        catch
-        {
-            // Ignore exception from MimeMessage.Load
+            BodyAsMimeMessage = mimeMessage;
         }
 #endif
     }

src/WireMock.Net.Minimal/Serialization/MatcherMapper.cs

@@ -55,7 +55,12 @@ internal class MatcherMapper
             case "CSharpCodeMatcher":
                 if (_settings.AllowCSharpCodeMatcher == true)
                 {
-                    return TypeLoader.LoadNewInstance<ICSharpCodeMatcher>(matchBehaviour, matchOperator, stringPatterns);
+                    if (TypeLoader.TryLoadNewInstance<ICSharpCodeMatcher>(out var csharpCodeMatcher, matchBehaviour, matchOperator, stringPatterns))
+                    {
+                        return csharpCodeMatcher;
+                    }
+
+                    throw new InvalidOperationException("The 'CSharpCodeMatcher' cannot be loaded. Please install the WireMock.Net.Matchers.CSharpCode package.");
                 }
 
                 throw new NotSupportedException("It's not allowed to use the 'CSharpCodeMatcher' because WireMockServerSettings.AllowCSharpCodeMatcher is not set to 'true'.");
@@ -75,7 +80,12 @@ internal class MatcherMapper
             case "GraphQLMatcher":
                 var patternAsString = stringPatterns[0].GetPattern();
                 var schema = new AnyOf<string, StringPattern, ISchemaData>(patternAsString);
-                return TypeLoader.LoadNewInstance<IGraphQLMatcher>(schema, matcherModel.CustomScalars, matchBehaviour, matchOperator);
+                if (TypeLoader.TryLoadNewInstance<IGraphQLMatcher>(out var graphQLMatcher, schema, matcherModel.CustomScalars, matchBehaviour, matchOperator))
+                {
+                    return graphQLMatcher;
+                }
+
+                throw new InvalidOperationException("The 'GraphQLMatcher' cannot be loaded. Please install the WireMock.Net.GraphQL package.");
 
             case "MimePartMatcher":
                 return CreateMimePartMatcher(matchBehaviour, matcherModel);
@@ -282,18 +292,34 @@ internal class MatcherMapper
         var contentTransferEncodingMatcher = Map(matcher.ContentTransferEncodingMatcher) as IStringMatcher;
         var contentMatcher = Map(matcher.ContentMatcher);
 
-        return TypeLoader.LoadNewInstance<IMimePartMatcher>(matchBehaviour, contentTypeMatcher, contentDispositionMatcher, contentTransferEncodingMatcher, contentMatcher);
+        if (TypeLoader.TryLoadNewInstance<IMimePartMatcher>(
+            out var mimePartMatcher,
+            matchBehaviour,
+            contentTypeMatcher,
+            contentDispositionMatcher,
+            contentTransferEncodingMatcher,
+            contentMatcher))
+        {
+            return mimePartMatcher;
+        }
+
+        throw new InvalidOperationException("The 'MimePartMatcher' cannot be loaded. Please install the WireMock.Net.MimePart package.");
     }
 
     private IProtoBufMatcher CreateProtoBufMatcher(MatchBehaviour? matchBehaviour, IReadOnlyList<string> protoDefinitions, MatcherModel matcher)
     {
         var objectMatcher = Map(matcher.ContentMatcher) as IObjectMatcher;
 
-        return TypeLoader.LoadNewInstance<IProtoBufMatcher>(
+        if (TypeLoader.TryLoadNewInstance<IProtoBufMatcher>(
+            out var protobufMatcher,
             () => ProtoDefinitionUtils.GetIdOrTexts(_settings, protoDefinitions.ToArray()),
             matcher.ProtoBufMessageType!,
             matchBehaviour ?? MatchBehaviour.AcceptOnMatch,
-            objectMatcher
-        );
+            objectMatcher))
+        {
+            return protobufMatcher;
+        }
+
+        throw new InvalidOperationException("The 'ProtoBufMatcher' cannot be loaded. Please install the WireMock.Net.ProtoBuf package.");
     }
 }

src/WireMock.Net.Minimal/Server/WireMockServer.ConvertMapping.cs

@@ -366,10 +366,8 @@ public partial class WireMockServer
         }
         else if (responseModel.BodyAsJson != null)
         {
-            if (responseModel.ProtoBufMessageType != null)
+            if (responseModel.ProtoBufMessageType != null && TypeLoader.TryLoadStaticInstance<IProtoBufUtils>(out var protoBufUtils))
             {
-                var protoBufUtils = TypeLoader.LoadStaticInstance<IProtoBufUtils>();
-
                 if (responseModel.ProtoDefinition != null)
                 {
                     responseBuilder = protoBufUtils.UpdateResponseBuilder(responseBuilder, responseModel.ProtoBufMessageType, responseModel.BodyAsJson, responseModel.ProtoDefinition);