Support for partial JSON matching (#539)

* support Json partial match with JsonPartialMatcher

* fix erroneous filenames

* add newline

* newlines fix

* add JsonPartialMatcher to mapper

* curly braces for ifs

* fix JToken type comparison

* more test cases

* rename AreEqual -> IsMatch + more test cases

* separate tests for JPath matcher values

Co-authored-by: Gleb Osokin <gleb.osokin@avira.com>

src/WireMock.Net/Matchers/JsonMatcher.cs

@@ -1,4 +1,5 @@
-using System.Collections;
+using System;
+using System.Collections;
 using System.Linq;
 using JetBrains.Annotations;
 using Newtonsoft.Json;
@@ -17,7 +18,7 @@ namespace WireMock.Matchers
         public object Value { get; }
 
         /// <inheritdoc cref="IMatcher.Name"/>
-        public string Name => "JsonMatcher";
+        public virtual string Name => "JsonMatcher";
 
         /// <inheritdoc cref="IMatcher.MatchBehaviour"/>
         public MatchBehaviour MatchBehaviour { get; }
@@ -29,6 +30,7 @@ namespace WireMock.Matchers
         public bool ThrowException { get; }
 
         private readonly JToken _valueAsJToken;
+        private readonly Func<JToken, JToken> _jTokenConverter;
 
         /// <summary>
         /// Initializes a new instance of the <see cref="JsonMatcher"/> class.
@@ -67,6 +69,9 @@ namespace WireMock.Matchers
 
             Value = value;
             _valueAsJToken = ConvertValueToJToken(value);
+            _jTokenConverter = ignoreCase
+                ? (Func<JToken, JToken>)Rename
+                : jToken => jToken;
         }
 
         /// <inheritdoc cref="IObjectMatcher.IsMatch"/>
@@ -81,7 +86,9 @@ namespace WireMock.Matchers
                 {
                     var inputAsJToken = ConvertValueToJToken(input);
 
-                    match = DeepEquals(_valueAsJToken, inputAsJToken);
+                    match = IsMatch(
+                        _jTokenConverter(_valueAsJToken),
+                        _jTokenConverter(inputAsJToken));
                 }
                 catch (JsonException)
                 {
@@ -95,6 +102,17 @@ namespace WireMock.Matchers
             return MatchBehaviourHelper.Convert(MatchBehaviour, MatchScores.ToScore(match));
         }
 
+        /// <summary>
+        /// Compares the input against the matcher value
+        /// </summary>
+        /// <param name="value">Matcher value</param>
+        /// <param name="input">Input value</param>
+        /// <returns></returns>
+        protected virtual bool IsMatch(JToken value, JToken input)
+        {
+            return JToken.DeepEquals(value, input);
+        }
+
         private static JToken ConvertValueToJToken(object value)
         {
             // Check if JToken, string, IEnumerable or object
@@ -114,19 +132,6 @@ namespace WireMock.Matchers
             }
         }
 
-        private bool DeepEquals(JToken value, JToken input)
-        {
-            if (!IgnoreCase)
-            {
-                return JToken.DeepEquals(value, input);
-            }
-
-            JToken renamedValue = Rename(value);
-            JToken renamedInput = Rename(input);
-
-            return JToken.DeepEquals(renamedValue, renamedInput);
-        }
-
         private static string ToUpper(string input)
         {
             return input?.ToUpperInvariant();

src/WireMock.Net/Matchers/JsonPartialMatcher.cs

@@ -0,0 +1,87 @@
+using System.Collections.Generic;
+using System.Linq;
+using JetBrains.Annotations;
+using Newtonsoft.Json.Linq;
+
+namespace WireMock.Matchers
+{
+    /// <summary>
+    /// JsonPartialMatcher
+    /// </summary>
+    public class JsonPartialMatcher : JsonMatcher
+    {
+        /// <inheritdoc cref="IMatcher.Name"/>
+        public override string Name => "JsonPartialMatcher";
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="JsonPartialMatcher"/> class.
+        /// </summary>
+        /// <param name="value">The string value to check for equality.</param>
+        /// <param name="ignoreCase">Ignore the case from the PropertyName and PropertyValue (string only).</param>
+        /// <param name="throwException">Throw an exception when the internal matching fails because of invalid input.</param>
+        public JsonPartialMatcher([NotNull] string value, bool ignoreCase = false, bool throwException = false) 
+            : base(value, ignoreCase, throwException)
+        {
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="JsonPartialMatcher"/> class.
+        /// </summary>
+        /// <param name="value">The object value to check for equality.</param>
+        /// <param name="ignoreCase">Ignore the case from the PropertyName and PropertyValue (string only).</param>
+        /// <param name="throwException">Throw an exception when the internal matching fails because of invalid input.</param>
+        public JsonPartialMatcher([NotNull] object value, bool ignoreCase = false, bool throwException = false) 
+            : base(value, ignoreCase, throwException)
+        {
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="JsonPartialMatcher"/> class.
+        /// </summary>
+        /// <param name="matchBehaviour">The match behaviour.</param>
+        /// <param name="value">The value to check for equality.</param>
+        /// <param name="ignoreCase">Ignore the case from the PropertyName and PropertyValue (string only).</param>
+        /// <param name="throwException">Throw an exception when the internal matching fails because of invalid input.</param>
+        public JsonPartialMatcher(MatchBehaviour matchBehaviour, [NotNull] object value, bool ignoreCase = false, bool throwException = false) 
+            : base(matchBehaviour, value, ignoreCase, throwException)
+        {
+        }
+
+        /// <inheritdoc />
+        protected override bool IsMatch(JToken value, JToken input)
+        {
+            if (value == null || value == input)
+            {
+                return true;
+            }
+
+            if (input == null || value.Type != input.Type)
+            {
+                return false;
+            }
+
+            switch (value.Type)
+            {
+                case JTokenType.Object:
+                    var nestedValues = value.ToObject<Dictionary<string, JToken>>();
+                    return nestedValues?.Any() != true ||
+                           nestedValues.All(pair => IsMatch(pair.Value, input.SelectToken(pair.Key)));
+
+                case JTokenType.Array:
+                    var valuesArray = value.ToObject<JToken[]>();
+                    var tokenArray = input.ToObject<JToken[]>();
+
+                    if (valuesArray?.Any() != true)
+                    {
+                        return true;
+                    }
+
+                    return tokenArray?.Any() == true &&
+                           valuesArray.All(subFilter => tokenArray.Any(subToken => IsMatch(subFilter, subToken)));
+
+                default:
+                    return value.ToString() == input.ToString();
+            }
+        }
+    }
+}

src/WireMock.Net/Serialization/MatcherMapper.cs

@@ -67,6 +67,10 @@ namespace WireMock.Serialization
                     object value = matcher.Pattern ?? matcher.Patterns;
                     return new JsonMatcher(matchBehaviour, value, ignoreCase, throwExceptionWhenMatcherFails);
 
+                case "JsonPartialMatcher":
+                    object matcherValue = matcher.Pattern ?? matcher.Patterns;
+                    return new JsonPartialMatcher(matchBehaviour, matcherValue, ignoreCase, throwExceptionWhenMatcherFails);
+
                 case "JsonPathMatcher":
                     return new JsonPathMatcher(matchBehaviour, throwExceptionWhenMatcherFails, stringPatterns);