Add WithProbability (#922)

* WithProbability

* fix

* x

* ,

* .

* .

* .

src/WireMock.Net.Abstractions/Admin/Mappings/FaultModel.cs

@@ -1,19 +1,18 @@
-namespace WireMock.Admin.Mappings
+namespace WireMock.Admin.Mappings;
+
+/// <summary>
+/// Fault Model
+/// </summary>
+[FluentBuilder.AutoGenerateBuilder]
+public class FaultModel
 {
     /// <summary>
-    /// Fault Model
+    /// Gets or sets the fault. Can be null, "", NONE, EMPTY_RESPONSE or MALFORMED_RESPONSE_CHUNK.
     /// </summary>
-    [FluentBuilder.AutoGenerateBuilder]
+    public string? Type { get; set; }
-    public class FaultModel
-    {
-        /// <summary>
-        /// Gets or sets the fault. Can be null, "", NONE, EMPTY_RESPONSE, MALFORMED_RESPONSE_CHUNK or RANDOM_DATA_THEN_CLOSE.
-        /// </summary>
-        public string Type { get; set; }
 
-        /// <summary>
+    /// <summary>
-        /// Gets or sets the fault percentage.
+    /// Gets or sets the fault percentage.
-        /// </summary>
+    /// </summary>
-        public double? Percentage { get; set; }
+    public double? Percentage { get; set; }
-    }
 }

src/WireMock.Net.Abstractions/Admin/Mappings/MappingModel.cs

@@ -1,5 +1,4 @@
 using System;
-using System.Collections.Generic;
 using WireMock.Models;
 
 namespace WireMock.Admin.Mappings;
@@ -94,4 +93,9 @@ public class MappingModel
     /// </example>
     /// </summary>
     public object? Data { get; set; }
+
+    /// <summary> 
+    /// The probability when this request should be matched. Value is between 0 and 1. [Optional]
+    /// </summary>
+    public double? Probability { get; set; }
 }

src/WireMock.Net.Abstractions/ResponseBuilders/FaultType.cs

@@ -1,23 +1,23 @@
-namespace WireMock.ResponseBuilders
+// ReSharper disable InconsistentNaming
+namespace WireMock.ResponseBuilders;
+
+/// <summary>
+/// The FaultType enumeration
+/// </summary>
+public enum FaultType
 {
     /// <summary>
-    /// The FaultType enumeration
+    /// No Fault
     /// </summary>
-    public enum FaultType
+    NONE,
-    {
-        /// <summary>
-        /// No Fault
-        /// </summary>
-        NONE,
 
-        /// <summary>
+    /// <summary>
-        /// Return a completely empty response.
+    /// Return a completely empty response.
-        /// </summary>
+    /// </summary>
-        EMPTY_RESPONSE,
+    EMPTY_RESPONSE,
 
-        /// <summary>
+    /// <summary>
-        /// Send a defined status header, then garbage, then close the connection.
+    /// Send a defined status header, then garbage, then close the connection.
-        /// </summary>
+    /// </summary>
-        MALFORMED_RESPONSE_CHUNK
+    MALFORMED_RESPONSE_CHUNK
-    }
 }

src/WireMock.Net/IMapping.cs

@@ -1,5 +1,4 @@
 using System;
-using System.Collections.Generic;
 using System.Threading.Tasks;
 using WireMock.Matchers.Request;
 using WireMock.Models;
@@ -132,6 +131,11 @@ public interface IMapping
     /// </summary>
     object? Data { get; }
 
+    /// <summary> 
+    /// The probability when this request should be matched. Value is between 0 and 1. [Optional]
+    /// </summary>
+    double? Probability { get; }
+
     /// <summary>
     /// ProvideResponseAsync
     /// </summary>

src/WireMock.Net/Json/DynamicPropertyWithValue.cs

@@ -4,7 +4,7 @@ using System.Linq.Dynamic.Core;
 
 namespace WireMock.Json;
 
-public class DynamicPropertyWithValue : DynamicProperty
+internal class DynamicPropertyWithValue : DynamicProperty
 {
     public object? Value { get; }
 

src/WireMock.Net/Mapping.cs

@@ -75,6 +75,9 @@ public class Mapping : IMapping
     /// <inheritdoc />
     public object? Data { get; }
 
+    /// <inheritdoc />
+    public double? Probability { get; }
+
     /// <summary>
     /// Initializes a new instance of the <see cref="Mapping"/> class.
     /// </summary>
@@ -95,6 +98,7 @@ public class Mapping : IMapping
     /// <param name="useWebhooksFireAndForget">Use Fire and Forget for the defined webhook(s). [Optional]</param>
     /// <param name="timeSettings">The TimeSettings. [Optional]</param>
     /// <param name="data">The data object. [Optional]</param>
+    /// <param name="probability">Define the probability when this request should be matched. [Optional]</param>
     public Mapping(
         Guid guid,
         DateTime updatedAt,
@@ -112,7 +116,8 @@ public class Mapping : IMapping
         IWebhook[]? webhooks,
         bool? useWebhooksFireAndForget,
         ITimeSettings? timeSettings,
-        object? data)
+        object? data,
+        double? probability)
     {
         Guid = guid;
         UpdatedAt = updatedAt;
@@ -131,6 +136,7 @@ public class Mapping : IMapping
         UseWebhooksFireAndForget = useWebhooksFireAndForget;
         TimeSettings = timeSettings;
         Data = data;
+        Probability = probability;
     }
 
     /// <inheritdoc cref="IMapping.ProvideResponseAsync" />

src/WireMock.Net/MappingBuilder.cs

@@ -69,12 +69,7 @@ public class MappingBuilder : IMappingBuilder
     /// <inheritdoc />
     public MappingModel[] GetMappings()
     {
-        return GetMappingsInternal().Select(_mappingConverter.ToMappingModel).ToArray();
+        return GetNonAdminMappings().Select(_mappingConverter.ToMappingModel).ToArray();
-    }
-
-    internal IMapping[] GetMappingsInternal()
-    {
-        return _options.Mappings.Values.ToArray().Where(m => !m.IsAdminInterface).ToArray();
     }
 
     /// <inheritdoc />
@@ -86,7 +81,7 @@ public class MappingBuilder : IMappingBuilder
     /// <inheritdoc />
     public string? ToCSharpCode(Guid guid, MappingConverterType converterType)
     {
-        var mapping = GetMappingsInternal().FirstOrDefault(m => m.Guid == guid);
+        var mapping = GetNonAdminMappings().FirstOrDefault(m => m.Guid == guid);
         if (mapping is null)
         {
             return null;
@@ -101,7 +96,7 @@ public class MappingBuilder : IMappingBuilder
     {
         var sb = new StringBuilder();
         bool addStart = true;
-        foreach (var mapping in GetMappingsInternal())
+        foreach (var mapping in GetNonAdminMappings())
         {
             sb.AppendLine(_mappingConverter.ToCSharpCode(mapping, new MappingConverterSettings { AddStart = addStart, ConverterType = converterType }));
 
@@ -123,7 +118,7 @@ public class MappingBuilder : IMappingBuilder
     /// <inheritdoc />
     public void SaveMappingsToFolder(string? folder)
     {
-        foreach (var mapping in GetNonAdminMappings().Where(m => !m.IsAdminInterface))
+        foreach (var mapping in GetNonAdminMappings())
         {
             _mappingToFileSaver.SaveMappingToFile(mapping, folder);
         }
@@ -131,7 +126,7 @@ public class MappingBuilder : IMappingBuilder
 
     private IMapping[] GetNonAdminMappings()
     {
-        return _options.Mappings.Values.ToArray();
+        return _options.Mappings.Values.Where(m => !m.IsAdminInterface).OrderBy(m => m.UpdatedAt).ToArray();
     }
 
     private void RegisterMapping(IMapping mapping, bool saveToFile)

src/WireMock.Net/Matchers/Request/RequestMessageCompositeMatcher.cs

@@ -1,6 +1,5 @@
 using System.Collections.Generic;
 using System.Linq;
-using JetBrains.Annotations;
 using Stef.Validation;
 
 namespace WireMock.Matchers.Request;
@@ -25,9 +24,9 @@ public abstract class RequestMessageCompositeMatcher : IRequestMatcher
     /// </summary>
     /// <param name="requestMatchers">The request matchers.</param>
     /// <param name="type">The CompositeMatcherType type (Defaults to 'And')</param>
-    protected RequestMessageCompositeMatcher([NotNull] IEnumerable<IRequestMatcher> requestMatchers, CompositeMatcherType type = CompositeMatcherType.And)
+    protected RequestMessageCompositeMatcher(IEnumerable<IRequestMatcher> requestMatchers, CompositeMatcherType type = CompositeMatcherType.And)
     {
-        Guard.NotNull(requestMatchers, nameof(requestMatchers));
+        Guard.NotNull(requestMatchers);
 
         _type = type;
         RequestMatchers = requestMatchers;

src/WireMock.Net/Owin/AspNetCoreSelfHost.cs

@@ -11,6 +11,7 @@ using Microsoft.Extensions.DependencyInjection;
 using Stef.Validation;
 using WireMock.Logging;
 using WireMock.Owin.Mappers;
+using WireMock.Services;
 using WireMock.Util;
 
 namespace WireMock.Owin
@@ -66,6 +67,7 @@ namespace WireMock.Owin
                 {
                     services.AddSingleton(_wireMockMiddlewareOptions);
                     services.AddSingleton<IMappingMatcher, MappingMatcher>();
+                    services.AddSingleton<IRandomizerDoubleBetween0And1, RandomizerDoubleBetween0And1>();
                     services.AddSingleton<IOwinRequestMapper, OwinRequestMapper>();
                     services.AddSingleton<IOwinResponseMapper, OwinResponseMapper>();
 

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

@@ -62,11 +62,11 @@ namespace WireMock.Owin.Mappers
             switch (responseMessage.FaultType)
             {
                 case FaultType.EMPTY_RESPONSE:
-                    bytes = IsFault(responseMessage) ? new byte[0] : GetNormalBody(responseMessage);
+                    bytes = IsFault(responseMessage) ? EmptyArray<byte>.Value : GetNormalBody(responseMessage);
                     break;
 
                 case FaultType.MALFORMED_RESPONSE_CHUNK:
-                    bytes = GetNormalBody(responseMessage) ?? new byte[0];
+                    bytes = GetNormalBody(responseMessage) ?? EmptyArray<byte>.Value;
                     if (IsFault(responseMessage))
                     {
                         bytes = bytes.Take(bytes.Length / 2).Union(_randomizerBytes.Generate()).ToArray();
@@ -87,7 +87,7 @@ namespace WireMock.Owin.Mappers
 
                 case { } typeAsString when typeAsString == typeof(string):
                     // Note: this case will also match on null 
-                    int.TryParse(responseMessage.StatusCode as string, out int result);
+                    int.TryParse(responseMessage.StatusCode as string, out var result);
                     response.StatusCode = MapStatusCode(result);
                     break;
 

src/WireMock.Net/Owin/MappingMatcher.cs

@@ -1,18 +1,21 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
-using WireMock.Extensions;
 using Stef.Validation;
+using WireMock.Extensions;
+using WireMock.Services;
 
 namespace WireMock.Owin;
 
 internal class MappingMatcher : IMappingMatcher
 {
     private readonly IWireMockMiddlewareOptions _options;
+    private readonly IRandomizerDoubleBetween0And1 _randomizerDoubleBetween0And1;
 
-    public MappingMatcher(IWireMockMiddlewareOptions options)
+    public MappingMatcher(IWireMockMiddlewareOptions options, IRandomizerDoubleBetween0And1 randomizerDoubleBetween0And1)
     {
         _options = Guard.NotNull(options);
+        _randomizerDoubleBetween0And1 = Guard.NotNull(randomizerDoubleBetween0And1);
     }
 
     public (MappingMatcherResult? Match, MappingMatcherResult? Partial) FindBestMatch(RequestMessage request)
@@ -21,7 +24,12 @@ internal class MappingMatcher : IMappingMatcher
 
         var possibleMappings = new List<MappingMatcherResult>();
 
-        foreach (var mapping in _options.Mappings.Values.Where(m => m.TimeSettings.IsValid()))
+        var mappings = _options.Mappings.Values
+            .Where(m => m.TimeSettings.IsValid())
+            .Where(m => m.Probability is null || m.Probability <= _randomizerDoubleBetween0And1.Generate())
+            .ToArray();
+
+        foreach (var mapping in mappings)
         {
             try
             {

src/WireMock.Net/Owin/OwinSelfHost.cs

@@ -9,6 +9,9 @@ using JetBrains.Annotations;
 using WireMock.Logging;
 using WireMock.Owin.Mappers;
 using Stef.Validation;
+using RandomDataGenerator.FieldOptions;
+using RandomDataGenerator.Randomizers;
+using WireMock.Services;
 
 namespace WireMock.Owin;
 
@@ -70,7 +73,7 @@ internal class OwinSelfHost : IOwinSelfHost
         {
             var requestMapper = new OwinRequestMapper();
             var responseMapper = new OwinResponseMapper(_options);
-            var matcher = new MappingMatcher(_options);
+            var matcher = new MappingMatcher(_options, new RandomizerDoubleBetween0And1());
 
             Action<IAppBuilder> startup = app =>
             {

src/WireMock.Net/RequestBuilders/IRequestBuilder.cs

@@ -1,9 +1,8 @@
-namespace WireMock.RequestBuilders
+namespace WireMock.RequestBuilders;
+
+/// <summary>
+/// IRequestBuilder
+/// </summary>
+public interface IRequestBuilder : IClientIPRequestBuilder
 {
-    /// <summary>
-    /// IRequestBuilder
-    /// </summary>
-    public interface IRequestBuilder : IClientIPRequestBuilder
-    {
-    }
 }

src/WireMock.Net/RequestBuilders/Request.WithCookies.cs

@@ -1,82 +1,81 @@
-using System;
+using System;
 using System.Collections.Generic;
 using WireMock.Matchers;
 using WireMock.Matchers.Request;
 using Stef.Validation;
 
-namespace WireMock.RequestBuilders
+namespace WireMock.RequestBuilders;
+
+public partial class Request
 {
-    public partial class Request
+    /// <inheritdoc cref="ICookiesRequestBuilder.WithCookie(string, string, MatchBehaviour)"/>
+    public IRequestBuilder WithCookie(string name, string pattern, MatchBehaviour matchBehaviour)
     {
-        /// <inheritdoc cref="ICookiesRequestBuilder.WithCookie(string, string, MatchBehaviour)"/>
+        return WithCookie(name, pattern, true, matchBehaviour);
-        public IRequestBuilder WithCookie(string name, string pattern, MatchBehaviour matchBehaviour)
+    }
-        {
-            return WithCookie(name, pattern, true, matchBehaviour);
-        }
 
-        /// <inheritdoc cref="ICookiesRequestBuilder.WithCookie(string, string, bool, MatchBehaviour)"/>
+    /// <inheritdoc cref="ICookiesRequestBuilder.WithCookie(string, string, bool, MatchBehaviour)"/>
-        public IRequestBuilder WithCookie(string name, string pattern, bool ignoreCase = true, MatchBehaviour matchBehaviour = MatchBehaviour.AcceptOnMatch)
+    public IRequestBuilder WithCookie(string name, string pattern, bool ignoreCase = true, MatchBehaviour matchBehaviour = MatchBehaviour.AcceptOnMatch)
-        {
+    {
-            Guard.NotNull(name, nameof(name));
+        Guard.NotNull(name, nameof(name));
-            Guard.NotNull(pattern, nameof(pattern));
+        Guard.NotNull(pattern, nameof(pattern));
 
-            _requestMatchers.Add(new RequestMessageCookieMatcher(matchBehaviour, name, pattern, ignoreCase));
+        _requestMatchers.Add(new RequestMessageCookieMatcher(matchBehaviour, name, pattern, ignoreCase));
-            return this;
+        return this;
-        }
+    }
 
-        /// <inheritdoc cref="ICookiesRequestBuilder.WithCookie(string, string[], MatchBehaviour)"/>
+    /// <inheritdoc cref="ICookiesRequestBuilder.WithCookie(string, string[], MatchBehaviour)"/>
-        public IRequestBuilder WithCookie(string name, string[] patterns, MatchBehaviour matchBehaviour)
+    public IRequestBuilder WithCookie(string name, string[] patterns, MatchBehaviour matchBehaviour)
-        {
+    {
-            return WithCookie(name, patterns, true, matchBehaviour);
+        return WithCookie(name, patterns, true, matchBehaviour);
-        }
+    }
 
-        /// <inheritdoc cref="ICookiesRequestBuilder.WithCookie(string, string[], bool, MatchBehaviour)"/>
+    /// <inheritdoc cref="ICookiesRequestBuilder.WithCookie(string, string[], bool, MatchBehaviour)"/>
-        public IRequestBuilder WithCookie(string name, string[] patterns, bool ignoreCase = true, MatchBehaviour matchBehaviour = MatchBehaviour.AcceptOnMatch)
+    public IRequestBuilder WithCookie(string name, string[] patterns, bool ignoreCase = true, MatchBehaviour matchBehaviour = MatchBehaviour.AcceptOnMatch)
-        {
+    {
-            Guard.NotNull(name, nameof(name));
+        Guard.NotNull(name, nameof(name));
-            Guard.NotNull(patterns, nameof(patterns));
+        Guard.NotNull(patterns, nameof(patterns));
 
-            _requestMatchers.Add(new RequestMessageCookieMatcher(matchBehaviour, name, ignoreCase, patterns));
+        _requestMatchers.Add(new RequestMessageCookieMatcher(matchBehaviour, name, ignoreCase, patterns));
-            return this;
+        return this;
-        }
+    }
 
-        /// <inheritdoc cref="ICookiesRequestBuilder.WithCookie(string, IStringMatcher[])"/>
+    /// <inheritdoc cref="ICookiesRequestBuilder.WithCookie(string, IStringMatcher[])"/>
-        public IRequestBuilder WithCookie(string name, params IStringMatcher[] matchers)
+    public IRequestBuilder WithCookie(string name, params IStringMatcher[] matchers)
-        {
+    {
-            Guard.NotNull(name, nameof(name));
+        Guard.NotNull(name, nameof(name));
-            Guard.NotNullOrEmpty(matchers, nameof(matchers));
+        Guard.NotNullOrEmpty(matchers, nameof(matchers));
 
-            _requestMatchers.Add(new RequestMessageCookieMatcher(MatchBehaviour.AcceptOnMatch, name, false, matchers));
+        _requestMatchers.Add(new RequestMessageCookieMatcher(MatchBehaviour.AcceptOnMatch, name, false, matchers));
-            return this;
+        return this;
-        }
+    }
 
-        /// <inheritdoc cref="ICookiesRequestBuilder.WithCookie(string, bool, IStringMatcher[])"/>
+    /// <inheritdoc cref="ICookiesRequestBuilder.WithCookie(string, bool, IStringMatcher[])"/>
-        public IRequestBuilder WithCookie(string name, bool ignoreCase, params IStringMatcher[] matchers)
+    public IRequestBuilder WithCookie(string name, bool ignoreCase, params IStringMatcher[] matchers)
-        {
+    {
-            Guard.NotNull(name, nameof(name));
+        Guard.NotNull(name, nameof(name));
-            Guard.NotNullOrEmpty(matchers, nameof(matchers));
+        Guard.NotNullOrEmpty(matchers, nameof(matchers));
 
-            _requestMatchers.Add(new RequestMessageCookieMatcher(MatchBehaviour.AcceptOnMatch, name, ignoreCase, matchers));
+        _requestMatchers.Add(new RequestMessageCookieMatcher(MatchBehaviour.AcceptOnMatch, name, ignoreCase, matchers));
-            return this;
+        return this;
-        }
+    }
 
-        /// <inheritdoc cref="ICookiesRequestBuilder.WithCookie(string, IStringMatcher[])"/>
+    /// <inheritdoc cref="ICookiesRequestBuilder.WithCookie(string, IStringMatcher[])"/>
-        public IRequestBuilder WithCookie(string name, bool ignoreCase, MatchBehaviour matchBehaviour, params IStringMatcher[] matchers)
+    public IRequestBuilder WithCookie(string name, bool ignoreCase, MatchBehaviour matchBehaviour, params IStringMatcher[] matchers)
-        {
+    {
-            Guard.NotNull(name, nameof(name));
+        Guard.NotNull(name, nameof(name));
-            Guard.NotNullOrEmpty(matchers, nameof(matchers));
+        Guard.NotNullOrEmpty(matchers, nameof(matchers));
 
-            _requestMatchers.Add(new RequestMessageCookieMatcher(matchBehaviour, name, ignoreCase, matchers));
+        _requestMatchers.Add(new RequestMessageCookieMatcher(matchBehaviour, name, ignoreCase, matchers));
-            return this;
+        return this;
-        }
+    }
 
-        /// <inheritdoc cref="ICookiesRequestBuilder.WithCookie(Func{IDictionary{string, string}, bool}[])"/>
+    /// <inheritdoc cref="ICookiesRequestBuilder.WithCookie(Func{IDictionary{string, string}, bool}[])"/>
-        public IRequestBuilder WithCookie(params Func<IDictionary<string, string>, bool>[] funcs)
+    public IRequestBuilder WithCookie(params Func<IDictionary<string, string>, bool>[] funcs)
-        {
+    {
-            Guard.NotNullOrEmpty(funcs, nameof(funcs));
+        Guard.NotNullOrEmpty(funcs, nameof(funcs));
 
-            _requestMatchers.Add(new RequestMessageCookieMatcher(funcs));
+        _requestMatchers.Add(new RequestMessageCookieMatcher(funcs));
-            return this;
+        return this;
-        }
     }
 }

src/WireMock.Net/RequestBuilders/Request.WithParam.cs

@@ -7,86 +7,85 @@ using WireMock.Matchers.Request;
 using WireMock.Types;
 using Stef.Validation;
 
-namespace WireMock.RequestBuilders
+namespace WireMock.RequestBuilders;
+
+public partial class Request
 {
-    public partial class Request
+    /// <inheritdoc cref="IParamsRequestBuilder.WithParam(string, MatchBehaviour)"/>
+    public IRequestBuilder WithParam(string key, MatchBehaviour matchBehaviour = MatchBehaviour.AcceptOnMatch)
     {
-        /// <inheritdoc cref="IParamsRequestBuilder.WithParam(string, MatchBehaviour)"/>
+        return WithParam(key, false, matchBehaviour);
-        public IRequestBuilder WithParam(string key, MatchBehaviour matchBehaviour = MatchBehaviour.AcceptOnMatch)
+    }
-        {
-            return WithParam(key, false, matchBehaviour);
-        }
 
-        /// <inheritdoc cref="IParamsRequestBuilder.WithParam(string, bool, MatchBehaviour)"/>
+    /// <inheritdoc cref="IParamsRequestBuilder.WithParam(string, bool, MatchBehaviour)"/>
-        public IRequestBuilder WithParam(string key, bool ignoreCase, MatchBehaviour matchBehaviour = MatchBehaviour.AcceptOnMatch)
+    public IRequestBuilder WithParam(string key, bool ignoreCase, MatchBehaviour matchBehaviour = MatchBehaviour.AcceptOnMatch)
-        {
+    {
-            Guard.NotNull(key);
+        Guard.NotNull(key);
 
-            _requestMatchers.Add(new RequestMessageParamMatcher(matchBehaviour, key, ignoreCase));
+        _requestMatchers.Add(new RequestMessageParamMatcher(matchBehaviour, key, ignoreCase));
-            return this;
+        return this;
-        }
+    }
 
-        /// <inheritdoc cref="IParamsRequestBuilder.WithParam(string, string[])"/>
+    /// <inheritdoc cref="IParamsRequestBuilder.WithParam(string, string[])"/>
-        public IRequestBuilder WithParam(string key, params string[] values)
+    public IRequestBuilder WithParam(string key, params string[] values)
-        {
+    {
-            return WithParam(key, MatchBehaviour.AcceptOnMatch, false, values);
+        return WithParam(key, MatchBehaviour.AcceptOnMatch, false, values);
-        }
+    }
 
-        /// <inheritdoc cref="IParamsRequestBuilder.WithParam(string, bool, string[])"/>
+    /// <inheritdoc cref="IParamsRequestBuilder.WithParam(string, bool, string[])"/>
-        public IRequestBuilder WithParam(string key, bool ignoreCase, params string[] values)
+    public IRequestBuilder WithParam(string key, bool ignoreCase, params string[] values)
-        {
+    {
-            return WithParam(key, MatchBehaviour.AcceptOnMatch, ignoreCase, values);
+        return WithParam(key, MatchBehaviour.AcceptOnMatch, ignoreCase, values);
-        }
+    }
 
-        /// <inheritdoc cref="IParamsRequestBuilder.WithParam(string, IStringMatcher[])"/>
+    /// <inheritdoc cref="IParamsRequestBuilder.WithParam(string, IStringMatcher[])"/>
-        public IRequestBuilder WithParam(string key, params IStringMatcher[] matchers)
+    public IRequestBuilder WithParam(string key, params IStringMatcher[] matchers)
-        {
+    {
-            return WithParam(key, MatchBehaviour.AcceptOnMatch, false, matchers);
+        return WithParam(key, MatchBehaviour.AcceptOnMatch, false, matchers);
-        }
+    }
 
-        /// <inheritdoc cref="IParamsRequestBuilder.WithParam(string, bool, IStringMatcher[])"/>
+    /// <inheritdoc cref="IParamsRequestBuilder.WithParam(string, bool, IStringMatcher[])"/>
-        public IRequestBuilder WithParam(string key, bool ignoreCase, params IStringMatcher[] matchers)
+    public IRequestBuilder WithParam(string key, bool ignoreCase, params IStringMatcher[] matchers)
-        {
+    {
-            return WithParam(key, MatchBehaviour.AcceptOnMatch, ignoreCase, matchers);
+        return WithParam(key, MatchBehaviour.AcceptOnMatch, ignoreCase, matchers);
-        }
+    }
 
-        /// <inheritdoc cref="IParamsRequestBuilder.WithParam(string, MatchBehaviour, string[])"/>
+    /// <inheritdoc cref="IParamsRequestBuilder.WithParam(string, MatchBehaviour, string[])"/>
-        public IRequestBuilder WithParam(string key, MatchBehaviour matchBehaviour, params string[] values)
+    public IRequestBuilder WithParam(string key, MatchBehaviour matchBehaviour, params string[] values)
-        {
+    {
-            return WithParam(key, matchBehaviour, false, values);
+        return WithParam(key, matchBehaviour, false, values);
-        }
+    }
 
-        /// <inheritdoc cref="IParamsRequestBuilder.WithParam(string, MatchBehaviour, bool, string[])"/>
+    /// <inheritdoc cref="IParamsRequestBuilder.WithParam(string, MatchBehaviour, bool, string[])"/>
-        public IRequestBuilder WithParam(string key, MatchBehaviour matchBehaviour, bool ignoreCase = false, params string[] values)
+    public IRequestBuilder WithParam(string key, MatchBehaviour matchBehaviour, bool ignoreCase = false, params string[] values)
-        {
+    {
-            Guard.NotNull(key);
+        Guard.NotNull(key);
 
-            _requestMatchers.Add(new RequestMessageParamMatcher(matchBehaviour, key, ignoreCase, values));
+        _requestMatchers.Add(new RequestMessageParamMatcher(matchBehaviour, key, ignoreCase, values));
-            return this;
+        return this;
-        }
+    }
 
-        /// <inheritdoc cref="IParamsRequestBuilder.WithParam(string, MatchBehaviour, IStringMatcher[])"/>
+    /// <inheritdoc cref="IParamsRequestBuilder.WithParam(string, MatchBehaviour, IStringMatcher[])"/>
-        public IRequestBuilder WithParam(string key, MatchBehaviour matchBehaviour, params IStringMatcher[] matchers)
+    public IRequestBuilder WithParam(string key, MatchBehaviour matchBehaviour, params IStringMatcher[] matchers)
-        {
+    {
-            return WithParam(key, matchBehaviour, false, matchers);
+        return WithParam(key, matchBehaviour, false, matchers);
-        }
+    }
 
-        /// <inheritdoc cref="IParamsRequestBuilder.WithParam(string, MatchBehaviour, bool, IStringMatcher[])"/>
+    /// <inheritdoc cref="IParamsRequestBuilder.WithParam(string, MatchBehaviour, bool, IStringMatcher[])"/>
-        public IRequestBuilder WithParam(string key, MatchBehaviour matchBehaviour, bool ignoreCase, params IStringMatcher[] matchers)
+    public IRequestBuilder WithParam(string key, MatchBehaviour matchBehaviour, bool ignoreCase, params IStringMatcher[] matchers)
-        {
+    {
-            Guard.NotNull(key);
+        Guard.NotNull(key);
 
-            _requestMatchers.Add(new RequestMessageParamMatcher(matchBehaviour, key, ignoreCase, matchers));
+        _requestMatchers.Add(new RequestMessageParamMatcher(matchBehaviour, key, ignoreCase, matchers));
-            return this;
+        return this;
-        }
+    }
 
-        /// <inheritdoc cref="IParamsRequestBuilder.WithParam(Func{IDictionary{string, WireMockList{string}}, bool}[])"/>
+    /// <inheritdoc cref="IParamsRequestBuilder.WithParam(Func{IDictionary{string, WireMockList{string}}, bool}[])"/>
-        public IRequestBuilder WithParam(params Func<IDictionary<string, WireMockList<string>>, bool>[] funcs)
+    public IRequestBuilder WithParam(params Func<IDictionary<string, WireMockList<string>>, bool>[] funcs)
-        {
+    {
-            Guard.NotNullOrEmpty(funcs, nameof(funcs));
+        Guard.NotNullOrEmpty(funcs, nameof(funcs));
 
-            _requestMatchers.Add(new RequestMessageParamMatcher(funcs));
+        _requestMatchers.Add(new RequestMessageParamMatcher(funcs));
-            return this;
+        return this;
-        }
     }
 }

src/WireMock.Net/RequestBuilders/Request.WithUrl.cs

@@ -3,47 +3,46 @@ using Stef.Validation;
 using WireMock.Matchers;
 using WireMock.Matchers.Request;
 
-namespace WireMock.RequestBuilders
+namespace WireMock.RequestBuilders;
+
+public partial class Request
 {
-    public partial class Request
+    /// <inheritdoc />
+    public IRequestBuilder WithUrl(params IStringMatcher[] matchers)
     {
-        /// <inheritdoc />
+        return WithUrl(MatchOperator.Or, matchers);
-        public IRequestBuilder WithUrl(params IStringMatcher[] matchers)
-        {
-            return WithUrl(MatchOperator.Or, matchers);
-        }
-
-        /// <inheritdoc />
-        public IRequestBuilder WithUrl(MatchOperator matchOperator, params IStringMatcher[] matchers)
-        {
-            Guard.NotNullOrEmpty(matchers);
-
-            _requestMatchers.Add(new RequestMessageUrlMatcher(MatchBehaviour.AcceptOnMatch, matchOperator, matchers));
-            return this;
-        }
-
-        /// <inheritdoc />
-        public IRequestBuilder WithUrl(params string[] urls)
-        {
-            return WithUrl(MatchOperator.Or, urls);
-        }
-
-        /// <inheritdoc />
-        public IRequestBuilder WithUrl(MatchOperator matchOperator, params string[] urls)
-        {
-            Guard.NotNullOrEmpty(urls);
-
-            _requestMatchers.Add(new RequestMessageUrlMatcher(MatchBehaviour.AcceptOnMatch, matchOperator, urls));
-            return this;
-        }
-
-        /// <inheritdoc cref="IUrlAndPathRequestBuilder.WithUrl(Func{string, bool}[])"/>
-        public IRequestBuilder WithUrl(params Func<string, bool>[] funcs)
-        {
-            Guard.NotNullOrEmpty(funcs);
-
-            _requestMatchers.Add(new RequestMessageUrlMatcher(funcs));
-            return this;
-        }
     }
-}
+
+    /// <inheritdoc />
+    public IRequestBuilder WithUrl(MatchOperator matchOperator, params IStringMatcher[] matchers)
+    {
+        Guard.NotNullOrEmpty(matchers);
+
+        _requestMatchers.Add(new RequestMessageUrlMatcher(MatchBehaviour.AcceptOnMatch, matchOperator, matchers));
+        return this;
+    }
+
+    /// <inheritdoc />
+    public IRequestBuilder WithUrl(params string[] urls)
+    {
+        return WithUrl(MatchOperator.Or, urls);
+    }
+
+    /// <inheritdoc />
+    public IRequestBuilder WithUrl(MatchOperator matchOperator, params string[] urls)
+    {
+        Guard.NotNullOrEmpty(urls);
+
+        _requestMatchers.Add(new RequestMessageUrlMatcher(MatchBehaviour.AcceptOnMatch, matchOperator, urls));
+        return this;
+    }
+
+    /// <inheritdoc cref="IUrlAndPathRequestBuilder.WithUrl(Func{string, bool}[])"/>
+    public IRequestBuilder WithUrl(params Func<string, bool>[] funcs)
+    {
+        Guard.NotNullOrEmpty(funcs);
+
+        _requestMatchers.Add(new RequestMessageUrlMatcher(funcs));
+        return this;
+    }
+}

src/WireMock.Net/RequestBuilders/Request.cs

@@ -63,5 +63,4 @@ public partial class Request : RequestMessageCompositeMatcher, IRequestBuilder
     {
         return _requestMatchers.OfType<T>().FirstOrDefault(func);
     }
-  
 }

src/WireMock.Net/Serialization/MappingConverter.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Globalization;
 using System.Linq;
 using System.Text;
 using System.Threading;
@@ -14,6 +15,7 @@ using WireMock.RequestBuilders;
 using WireMock.ResponseBuilders;
 using WireMock.Settings;
 using WireMock.Types;
+using WireMock.Util;
 
 namespace WireMock.Serialization;
 
@@ -33,7 +35,7 @@ internal class MappingConverter
         settings ??= new MappingConverterSettings();
 
         var request = (Request)mapping.RequestMatcher;
-        var response = (Response) mapping.Provider;
+        var response = (Response)mapping.Provider;
 
         var clientIPMatcher = request.GetRequestMessageMatcher<RequestMessageClientIPMatcher>();
         var pathMatcher = request.GetRequestMessageMatcher<RequestMessagePathMatcher>();
@@ -115,6 +117,11 @@ internal class MappingConverter
         // Guid
         sb.AppendLine($"    .WithGuid(\"{mapping.Guid}\")");
 
+        if (mapping.Probability != null)
+        {
+            sb.AppendLine($"    .WithProbability({mapping.Probability.Value.ToString(CultureInfoUtils.CultureInfoEnUS)})");
+        }
+
         // Response
         sb.AppendLine("    .RespondWith(Response.Create()");
 
@@ -183,6 +190,7 @@ internal class MappingConverter
             WhenStateIs = mapping.ExecutionConditionState,
             SetStateTo = mapping.NextState,
             Data = mapping.Data,
+            Probability = mapping.Probability,
             Request = new RequestModel
             {
                 Headers = headerMatchers.Any() ? headerMatchers.Select(hm => new HeaderModel

src/WireMock.Net/Serialization/ProxyMappingConverter.cs

@@ -189,7 +189,8 @@ internal class ProxyMappingConverter
             webhooks: null,
             useWebhooksFireAndForget: null,
             timeSettings: null,
-            data: mapping?.Data
+            data: mapping?.Data,
+            probability: null
         );
     }
 }

src/WireMock.Net/Server/IRespondWithAProvider.cs

@@ -175,5 +175,13 @@ public interface IRespondWithAProvider
     /// lookup data "1"
     /// </example>
     /// </summary>
+    /// <returns>The <see cref="IRespondWithAProvider"/>.</returns>
     IRespondWithAProvider WithData(object data);
+
+    /// <summary>
+    /// Define the probability when this request should be matched. Value is between 0 and 1.
+    /// </summary>
+    /// <param name="probability">The probability when this request should be matched. Value is between 0 and 1.</param>
+    /// <returns>The <see cref="IRespondWithAProvider"/>.</returns>
+    IRespondWithAProvider WithProbability(double probability);
 }

src/WireMock.Net/Server/RespondWithAProvider.cs

@@ -18,6 +18,12 @@ namespace WireMock.Server;
 /// </summary>
 internal class RespondWithAProvider : IRespondWithAProvider
 {
+    private readonly RegistrationCallback _registrationCallback;
+    private readonly IRequestMatcher _requestMatcher;
+    private readonly WireMockServerSettings _settings;
+    private readonly IDateTimeUtils _dateTimeUtils;
+    private readonly bool _saveToFile;
+
     private int _priority;
     private string? _title;
     private string? _description;
@@ -26,13 +32,8 @@ internal class RespondWithAProvider : IRespondWithAProvider
     private string? _nextState;
     private string? _scenario;
     private int _timesInSameState = 1;
-    private readonly RegistrationCallback _registrationCallback;
-    private readonly IRequestMatcher _requestMatcher;
-    private readonly WireMockServerSettings _settings;
-    private readonly IDateTimeUtils _dateTimeUtils;
-    private readonly bool _saveToFile;
-
     private bool? _useWebhookFireAndForget;
+    private double? _probability;
 
     public Guid Guid { get; private set; }
 
@@ -92,7 +93,8 @@ internal class RespondWithAProvider : IRespondWithAProvider
             Webhooks,
             _useWebhookFireAndForget,
             TimeSettings,
-            Data);
+            Data,
+            _probability);
 
         _registrationCallback(mapping, _saveToFile);
     }
@@ -285,6 +287,13 @@ internal class RespondWithAProvider : IRespondWithAProvider
         return this;
     }
 
+    public IRespondWithAProvider WithProbability(double probability)
+    {
+        _probability = Guard.Condition(probability, p => p is >= 0 and <= 1.0);
+
+        return this;
+    }
+
     private static IWebhook InitWebhook(
         string url,
         string method,

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

@@ -113,6 +113,11 @@ public partial class WireMockServer
             respondProvider.WithWebhookFireAndForget(mappingModel.UseWebhooksFireAndForget.Value);
         }
 
+        if (mappingModel.Probability != null)
+        {
+            respondProvider.WithProbability(mappingModel.Probability.Value);
+        }
+
         var responseBuilder = InitResponseBuilder(mappingModel.Response);
         respondProvider.RespondWith(responseBuilder);
 

src/WireMock.Net/Services/IRandomizerDoubleBetween0And1.cs

@@ -0,0 +1,6 @@
+namespace WireMock.Services;
+
+internal interface IRandomizerDoubleBetween0And1
+{
+    double Generate();
+}

src/WireMock.Net/Services/RandomizerDoubleBetween0And1.cs

@@ -0,0 +1,14 @@
+using RandomDataGenerator.FieldOptions;
+using RandomDataGenerator.Randomizers;
+
+namespace WireMock.Services;
+
+internal class RandomizerDoubleBetween0And1 : IRandomizerDoubleBetween0And1
+{
+    private readonly IRandomizerNumber<double> _randomizerDoubleBetween0And1 = RandomizerFactory.GetRandomizer(new FieldOptionsDouble { Min = 0, Max = 1 });
+
+    public double Generate()
+    {
+        return _randomizerDoubleBetween0And1.Generate() ?? 0;
+    }
+}

src/WireMock.Net/Util/CultureInfoExtensions.cs

@@ -5,6 +5,8 @@ namespace WireMock.Util;
 
 internal static class CultureInfoUtils
 {
+    public static readonly CultureInfo CultureInfoEnUS = new("en-US");
+
     public static CultureInfo Parse(string? value)
     {
         if (value is null)

src/WireMock.Org.Abstractions/MappingsResponseFaultConstants.cs

@@ -1,16 +1,11 @@
-namespace WireMock.Org.Abstractions
+namespace WireMock.Org.Abstractions;
+
+/// <summary>
+/// The fault to apply (instead of a full, valid response).
+/// </summary>
+public static class MappingsResponseFaultConstants
 {
-    /// <summary>
+    public const string EMPTYRESPONSE = "EMPTY_RESPONSE";
-    /// The fault to apply (instead of a full, valid response).
-    /// </summary>
-    public static class MappingsResponseFaultConstants
-    {
-        public const string CONNECTIONRESETBYPEER = "CONNECTION_RESET_BY_PEER";
 
-        public const string EMPTYRESPONSE = "EMPTY_RESPONSE";
+    public const string MALFORMEDRESPONSECHUNK = "MALFORMED_RESPONSE_CHUNK";
-
+}
-        public const string MALFORMEDRESPONSECHUNK = "MALFORMED_RESPONSE_CHUNK";
-
-        public const string RANDOMDATATHENCLOSE = "RANDOM_DATA_THEN_CLOSE";
-    }
-}

test/WireMock.Net.Tests/Owin/MappingMatcherTests.cs

@@ -6,6 +6,7 @@ using WireMock.Logging;
 using WireMock.Matchers.Request;
 using WireMock.Models;
 using WireMock.Owin;
+using WireMock.Services;
 using WireMock.Util;
 using Xunit;
 
@@ -14,6 +15,8 @@ namespace WireMock.Net.Tests.Owin;
 public class MappingMatcherTests
 {
     private readonly Mock<IWireMockMiddlewareOptions> _optionsMock;
+    private readonly Mock<IRandomizerDoubleBetween0And1> _randomizerDoubleBetween0And1Mock;
+
     private readonly MappingMatcher _sut;
 
     public MappingMatcherTests()
@@ -29,7 +32,10 @@ public class MappingMatcherTests
         loggerMock.Setup(l => l.Error(It.IsAny<string>()));
         _optionsMock.Setup(o => o.Logger).Returns(loggerMock.Object);
 
-        _sut = new MappingMatcher(_optionsMock.Object);
+        _randomizerDoubleBetween0And1Mock = new Mock<IRandomizerDoubleBetween0And1>();
+        _randomizerDoubleBetween0And1Mock.Setup(r => r.Generate()).Returns(0.0);
+
+        _sut = new MappingMatcher(_optionsMock.Object, _randomizerDoubleBetween0And1Mock.Object);
     }
 
     [Fact]
@@ -76,8 +82,8 @@ public class MappingMatcherTests
         var guid2 = Guid.Parse("00000000-0000-0000-0000-000000000002");
         var mappings = InitMappings
         (
-            (guid1, new[] { 0.1 }),
+            (guid1, new[] { 0.1 }, null),
-            (guid2, new[] { 1.0 })
+            (guid2, new[] { 1.0 }, null)
         );
         _optionsMock.Setup(o => o.Mappings).Returns(mappings);
 
@@ -104,8 +110,8 @@ public class MappingMatcherTests
         var guid2 = Guid.Parse("00000000-0000-0000-0000-000000000002");
         var mappings = InitMappings
         (
-            (guid1, new[] { 0.1 }),
+            (guid1, new[] { 0.1 }, null),
-            (guid2, new[] { 0.9 })
+            (guid2, new[] { 0.9 }, null)
         );
         _optionsMock.Setup(o => o.Mappings).Returns(mappings);
 
@@ -131,8 +137,8 @@ public class MappingMatcherTests
 
         _optionsMock.SetupGet(o => o.AllowPartialMapping).Returns(true);
         var mappings = InitMappings(
-            (guid1, new[] { 0.1 }),
+            (guid1, new[] { 0.1 }, null),
-            (guid2, new[] { 0.9 })
+            (guid2, new[] { 0.9 }, null)
         );
         _optionsMock.Setup(o => o.Mappings).Returns(mappings);
 
@@ -158,8 +164,8 @@ public class MappingMatcherTests
         var guid1 = Guid.Parse("00000000-0000-0000-0000-000000000001");
         var guid2 = Guid.Parse("00000000-0000-0000-0000-000000000002");
         var mappings = InitMappings(
-            (guid1, new[] { 1.0 }),
+            (guid1, new[] { 1.0 }, null),
-            (guid2, new[] { 1.0, 1.0 })
+            (guid2, new[] { 1.0, 1.0 }, null)
         );
         _optionsMock.Setup(o => o.Mappings).Returns(mappings);
 
@@ -178,7 +184,31 @@ public class MappingMatcherTests
         result.Partial.RequestMatchResult.AverageTotalScore.Should().Be(1.0);
     }
 
-    private static ConcurrentDictionary<Guid, IMapping> InitMappings(params (Guid guid, double[] scores)[] matches)
+    [Fact]
+    public void MappingMatcher_FindBestMatch_WhenProbabilityFailsFirst_ShouldReturnSecondMatch()
+    {
+        // Assign
+        var guid1 = Guid.Parse("00000000-0000-0000-0000-000000000001");
+        var guid2 = Guid.Parse("00000000-0000-0000-0000-000000000002");
+        var mappings = InitMappings
+        (
+            (guid1, new[] { 1.0 }, 1.0),
+            (guid2, new[] { 1.0 }, null)
+        );
+        _optionsMock.Setup(o => o.Mappings).Returns(mappings);
+
+        var request = new RequestMessage(new UrlDetails("http://localhost/foo"), "GET", "::1");
+
+        // Act
+        var result = _sut.FindBestMatch(request);
+
+        // Assert
+        result.Match.Should().NotBeNull();
+        result.Match!.Mapping.Guid.Should().Be(guid2);
+        result.Match.RequestMatchResult.AverageTotalScore.Should().Be(1.0);
+    }
+
+    private static ConcurrentDictionary<Guid, IMapping> InitMappings(params (Guid guid, double[] scores, double? probability)[] matches)
     {
         var mappings = new ConcurrentDictionary<Guid, IMapping>();
 
@@ -193,6 +223,8 @@ public class MappingMatcherTests
                 requestMatchResult.AddScore(typeof(object), score);
             }
 
+            mappingMock.SetupGet(m => m.Probability).Returns(match.probability);
+
             mappingMock.Setup(m => m.GetRequestMatchResult(It.IsAny<RequestMessage>(), It.IsAny<string>())).Returns(requestMatchResult);
 
             mappings.TryAdd(match.guid, mappingMock.Object);

test/WireMock.Net.Tests/Owin/WireMockMiddlewareTests.cs

@@ -177,7 +177,7 @@ public class WireMockMiddlewareTests
         _mappingMock.SetupGet(m => m.Provider).Returns(responseBuilder);
         _mappingMock.SetupGet(m => m.Settings).Returns(settings);
 
-        var newMappingFromProxy = new Mapping(Guid.NewGuid(), _updatedAt, string.Empty, string.Empty, null, settings, Request.Create(), Response.Create(), 0, null, null, null, null, null, false, null, null);
+        var newMappingFromProxy = new Mapping(Guid.NewGuid(), _updatedAt, string.Empty, string.Empty, null, settings, Request.Create(), Response.Create(), 0, null, null, null, null, null, false, null, null, null);
         _mappingMock.Setup(m => m.ProvideResponseAsync(It.IsAny<RequestMessage>())).ReturnsAsync((new ResponseMessage(), newMappingFromProxy));
 
         var requestBuilder = Request.Create().UsingAnyMethod();
@@ -231,7 +231,7 @@ public class WireMockMiddlewareTests
         _mappingMock.SetupGet(m => m.Provider).Returns(responseBuilder);
         _mappingMock.SetupGet(m => m.Settings).Returns(settings);
 
-        var newMappingFromProxy = new Mapping(Guid.NewGuid(), _updatedAt, "my-title", "my-description", null, settings, Request.Create(), Response.Create(), 0, null, null, null, null, null, false, null, data: null);
+        var newMappingFromProxy = new Mapping(Guid.NewGuid(), _updatedAt, "my-title", "my-description", null, settings, Request.Create(), Response.Create(), 0, null, null, null, null, null, false, null, data: null, probability: null);
         _mappingMock.Setup(m => m.ProvideResponseAsync(It.IsAny<RequestMessage>())).ReturnsAsync((new ResponseMessage(), newMappingFromProxy));
 
         var requestBuilder = Request.Create().UsingAnyMethod();

test/WireMock.Net.Tests/Serialization/MappingConverterTests.ToCSharpCode.cs

@@ -136,7 +136,8 @@ public partial class MappingConverterTests
             null,
             false,
             null,
-            data: null
+            data: null,
+            probability: 0.3
         );
     }
 }

test/WireMock.Net.Tests/Serialization/MappingConverterTests.ToCSharpCode_With_Builder_And_AddStartIsFalse.verified.txt

@@ -9,6 +9,7 @@
         .WithBody("b")
     )
     .WithGuid("8e7b9ab7-e18e-4502-8bc9-11e6679811cc")
+    .WithProbability(0.3)
     .RespondWith(Response.Create()
         .WithHeader("Keep-Alive)", "test")
         .WithBody("bbb")

test/WireMock.Net.Tests/Serialization/MappingConverterTests.ToCSharpCode_With_Builder_And_AddStartIsTrue.verified.txt

@@ -10,6 +10,7 @@ builder
         .WithBody("b")
     )
     .WithGuid("8e7b9ab7-e18e-4502-8bc9-11e6679811cc")
+    .WithProbability(0.3)
     .RespondWith(Response.Create()
         .WithHeader("Keep-Alive)", "test")
         .WithBody("bbb")

test/WireMock.Net.Tests/Serialization/MappingConverterTests.ToCSharpCode_With_Server_And_AddStartIsFalse.verified.txt

@@ -9,6 +9,7 @@
         .WithBody("b")
     )
     .WithGuid("8e7b9ab7-e18e-4502-8bc9-11e6679811cc")
+    .WithProbability(0.3)
     .RespondWith(Response.Create()
         .WithHeader("Keep-Alive)", "test")
         .WithBody("bbb")

test/WireMock.Net.Tests/Serialization/MappingConverterTests.ToCSharpCode_With_Server_And_AddStartIsTrue.verified.txt

@@ -10,6 +10,7 @@ server
         .WithBody("b")
     )
     .WithGuid("8e7b9ab7-e18e-4502-8bc9-11e6679811cc")
+    .WithProbability(0.3)
     .RespondWith(Response.Create()
         .WithHeader("Keep-Alive)", "test")
         .WithBody("bbb")

test/WireMock.Net.Tests/Serialization/MappingConverterTests.ToMappingModel_WithProbability_ReturnsCorrectModel.verified.txt

@@ -0,0 +1,11 @@
+{
+  Guid: Guid_1,
+  UpdatedAt: DateTime_1,
+  Title: ,
+  Description: ,
+  Priority: 42,
+  Request: {},
+  Response: {},
+  UseWebhooksFireAndForget: false,
+  Probability: 0.4
+}

test/WireMock.Net.Tests/Serialization/MappingConverterTests.cs

@@ -57,7 +57,7 @@ public partial class MappingConverterTests
                 }
             }
         };
-        var mapping = new Mapping(_guid, _updatedAt, string.Empty, string.Empty, null, _settings, request, response, 0, null, null, null, null, webhooks, false, null, data: null);
+        var mapping = new Mapping(_guid, _updatedAt, string.Empty, string.Empty, null, _settings, request, response, 0, null, null, null, null, webhooks, false, null, data: null, probability: null);
 
         // Act
         var model = _sut.ToMappingModel(mapping);
@@ -130,7 +130,7 @@ public partial class MappingConverterTests
                 }
             }
         };
-        var mapping = new Mapping(_guid, _updatedAt, string.Empty, string.Empty, null, _settings, request, response, 0, null, null, null, null, webhooks, true, null, data: null);
+        var mapping = new Mapping(_guid, _updatedAt, string.Empty, string.Empty, null, _settings, request, response, 0, null, null, null, null, webhooks, true, null, data: null, probability: null);
 
         // Act
         var model = _sut.ToMappingModel(mapping);
@@ -168,7 +168,7 @@ public partial class MappingConverterTests
         var description = "my-description";
         var request = Request.Create();
         var response = Response.Create();
-        var mapping = new Mapping(_guid, _updatedAt, title, description, null, _settings, request, response, 0, null, null, null, null, null, false, null, data: null);
+        var mapping = new Mapping(_guid, _updatedAt, title, description, null, _settings, request, response, 0, null, null, null, null, null, false, null, data: null, probability: null);
 
         // Act
         var model = _sut.ToMappingModel(mapping);
@@ -188,7 +188,7 @@ public partial class MappingConverterTests
         // Assign
         var request = Request.Create();
         var response = Response.Create().WithBodyAsJson(new { x = "x" }).WithTransformer();
-        var mapping = new Mapping(_guid, _updatedAt, string.Empty, string.Empty, null, _settings, request, response, 42, null, null, null, null, null, false, null, data: null);
+        var mapping = new Mapping(_guid, _updatedAt, string.Empty, string.Empty, null, _settings, request, response, 42, null, null, null, null, null, false, null, data: null, probability: null);
 
         // Act
         var model = _sut.ToMappingModel(mapping);
@@ -217,7 +217,7 @@ public partial class MappingConverterTests
             End = end,
             TTL = ttl
         };
-        var mapping = new Mapping(_guid, _updatedAt, string.Empty, string.Empty, null, _settings, request, response, 42, null, null, null, null, null, false, timeSettings, data: null);
+        var mapping = new Mapping(_guid, _updatedAt, string.Empty, string.Empty, null, _settings, request, response, 42, null, null, null, null, null, false, timeSettings, data: null, probability: null);
 
         // Act
         var model = _sut.ToMappingModel(mapping);
@@ -248,7 +248,7 @@ public partial class MappingConverterTests
         {
             var request = Request.Create();
             var response = Response.Create().WithDelay(test.Delay);
-            var mapping = new Mapping(Guid.NewGuid(), _updatedAt, string.Empty, string.Empty, string.Empty, _settings, request, response, 42, null, null, null, null, null, false, null, data: null);
+            var mapping = new Mapping(Guid.NewGuid(), _updatedAt, string.Empty, string.Empty, string.Empty, _settings, request, response, 42, null, null, null, null, null, false, null, data: null, probability: null);
 
             // Act
             var model = _sut.ToMappingModel(mapping);
@@ -266,7 +266,7 @@ public partial class MappingConverterTests
         var delay = 1000;
         var request = Request.Create();
         var response = Response.Create().WithDelay(delay);
-        var mapping = new Mapping(_guid, _updatedAt, string.Empty, string.Empty, null, _settings, request, response, 42, null, null, null, null, null, false, null, data: null);
+        var mapping = new Mapping(_guid, _updatedAt, string.Empty, string.Empty, null, _settings, request, response, 42, null, null, null, null, null, false, null, data: null, probability: null);
 
         // Act
         var model = _sut.ToMappingModel(mapping);
@@ -286,7 +286,7 @@ public partial class MappingConverterTests
         int minimumDelay = 1000;
         var request = Request.Create();
         var response = Response.Create().WithRandomDelay(minimumDelay);
-        var mapping = new Mapping(_guid, _updatedAt, string.Empty, string.Empty, null, _settings, request, response, 42, null, null, null, null, null, false, null, data: null);
+        var mapping = new Mapping(_guid, _updatedAt, string.Empty, string.Empty, null, _settings, request, response, 42, null, null, null, null, null, false, null, data: null, probability: null);
 
         // Act
         var model = _sut.ToMappingModel(mapping);
@@ -309,7 +309,7 @@ public partial class MappingConverterTests
         int maximumDelay = 2000;
         var request = Request.Create();
         var response = Response.Create().WithRandomDelay(minimumDelay, maximumDelay);
-        var mapping = new Mapping(_guid, _updatedAt, string.Empty, string.Empty, null, _settings, request, response, 42, null, null, null, null, null, false, null, data: null);
+        var mapping = new Mapping(_guid, _updatedAt, string.Empty, string.Empty, null, _settings, request, response, 42, null, null, null, null, null, false, null, data: null, probability: null);
 
         // Act
         var model = _sut.ToMappingModel(mapping);
@@ -323,5 +323,25 @@ public partial class MappingConverterTests
         // Verify
         return Verifier.Verify(model);
     }
+
+    [Fact]
+    public Task ToMappingModel_WithProbability_ReturnsCorrectModel()
+    {
+        // Assign
+        double probability = 0.4;
+        var request = Request.Create();
+        var response = Response.Create();
+        var mapping = new Mapping(_guid, _updatedAt, string.Empty, string.Empty, null, _settings, request, response, 42, null, null, null, null, null, false, null, data: null, probability: probability);
+
+        // Act
+        var model = _sut.ToMappingModel(mapping);
+
+        // Assert
+        model.Should().NotBeNull();
+        model.Probability.Should().Be(0.4);
+
+        // Verify
+        return Verifier.Verify(model);
+    }
 }
 #endif

test/WireMock.Net.Tests/WireMockServerTests.WithProbability.cs

@@ -0,0 +1,37 @@
+using System;
+using System.Linq;
+using System.Net;
+using System.Threading.Tasks;
+using WireMock.RequestBuilders;
+using WireMock.ResponseBuilders;
+using WireMock.Server;
+using Xunit;
+
+namespace WireMock.Net.Tests;
+
+public partial class WireMockServerTests
+{
+    [Fact]
+    public async Task WireMockServer_WithProbability()
+    {
+        // Arrange
+        var server = WireMockServer.Start();
+        server
+            .Given(Request.Create().UsingGet().WithPath("/foo"))
+            .WithProbability(0.5)
+            .RespondWith(Response.Create().WithStatusCode(200));
+
+        server
+            .Given(Request.Create().UsingGet().WithPath("/foo"))
+            .RespondWith(Response.Create().WithStatusCode(500));
+
+        // Act
+        var requestUri = new Uri($"http://localhost:{server.Port}/foo");
+        var response = await server.CreateClient().GetAsync(requestUri).ConfigureAwait(false);
+
+        // Assert
+        Assert.True(new[] { HttpStatusCode.OK, HttpStatusCode.InternalServerError }.Contains(response.StatusCode));
+
+        server.Stop();
+    }
+}