2610 assert unique json ids

src/Hl7.Fhir.Base/Serialization/BaseFhirJsonPocoDeserializer.cs

@@ -254,6 +254,10 @@ private void deserializeObjectInto<T>(
             while (reader.TokenType != JsonTokenType.EndObject)
             {
                 var currentPropertyName = reader.GetString()!;
+                if (!objectParsingState.TryAddToEncounteredKeys(currentPropertyName))
+                {
+                    state.Errors.Add(ERR.DUPLICATE_KEY(ref reader, state.Path.GetInstancePath(), currentPropertyName));
+                }
 
                 // The resourceType property on the level of a resource is used to determine
                 // the type and should otherwise be skipped when processing a resource.
@@ -383,7 +387,7 @@ FhirJsonPocoDeserializerState state
 
                 // If this is a FhirPrimitive, make sure we delay validation until we had the
                 // chance to encounter both the `name` and `_name` property.
-                if (delayedValidations is not null && propertyValueMapping.IsFhirPrimitive)
+                if (propertyValueMapping.IsFhirPrimitive)
                 {
                     delayedValidations.ScheduleDelayedValidation(
                         propertyMapping.Name + PROPERTY_VALIDATION_KEY_SUFFIX,
@@ -458,11 +462,12 @@ internal class ObjectParsingState
         {
             private readonly Dictionary<string, Action> _validations = new();
             private readonly Dictionary<string, int> _parsedPropValue = new();
+            private readonly HashSet<string> _encounteredIDs = new();
 
             public int GetPropertyIndex(string memberName)
             {
-                if (_parsedPropValue.ContainsKey(memberName))
-                    return _parsedPropValue[memberName];
+                if (_parsedPropValue.TryGetValue(memberName, out int index))
+                    return index;
                 _parsedPropValue.Add(memberName, 0);
                 return 0;
             }
@@ -472,6 +477,11 @@ public void SetPropertyIndex(string memberName, int count)
                 _parsedPropValue[memberName] = count;
             }
 
+            public bool TryAddToEncounteredKeys(string key)
+            {
+                return _encounteredIDs.Add(key);
+            }
+
             public void ScheduleDelayedValidation(string key, Action validation)
             {
                 // Add or overwrite the entry for the given key.
@@ -926,7 +936,7 @@ private static (PropertyMapping? propMapping, ClassMapping? propValueMapping, Fh
             (ClassMapping? propertyValueMapping, FhirJsonException? error) = propertyMapping.Choice switch
             {
                 ChoiceType.None or ChoiceType.ResourceChoice =>
-                    inspector.FindOrImportClassMapping(propertyMapping.GetInstantiableType()) is ClassMapping m
+                    inspector.FindOrImportClassMapping(propertyMapping.GetInstantiableType()) is { } m
                         ? (m, null)
                         : throw new InvalidOperationException($"Encountered property type {propertyMapping.ImplementingType} for which no mapping was found in the model assemblies. " + reader.GenerateLocationMessage()),
                 ChoiceType.DatatypeChoice => getChoiceClassMapping(ref reader),
@@ -941,7 +951,7 @@ private static (PropertyMapping? propMapping, ClassMapping? propValueMapping, Fh
 
                 return string.IsNullOrEmpty(typeSuffix)
                     ? (null, ERR.CHOICE_ELEMENT_HAS_NO_TYPE(ref r, path.GetInstancePath(), propertyMapping.Name))
-                    : inspector.FindClassMapping(typeSuffix) is ClassMapping cm
+                    : inspector.FindClassMapping(typeSuffix) is { } cm
                         ? (cm, null)
                         : (default, ERR.CHOICE_ELEMENT_HAS_UNKOWN_TYPE(ref r, path.GetInstancePath(), propertyMapping.Name, typeSuffix));
             }

src/Hl7.Fhir.Base/Serialization/FhirJsonException.cs

@@ -61,6 +61,7 @@ public class FhirJsonException : ExtendedCodedException
         public const string PROPERTY_MAY_NOT_BE_EMPTY_CODE = "JSON127";
 
         public const string DUPLICATE_ARRAY_CODE = "JSON128";
+        public const string DUPLICATE_KEYS_CODE = "JSON129";
 
         // ==========================================
         // Unrecoverable Errors
@@ -76,6 +77,7 @@ public class FhirJsonException : ExtendedCodedException
         internal static FhirJsonException RESOURCE_TYPE_NOT_A_RESOURCE(ref Utf8JsonReader reader, string instancePath, string name) => Initialize(ref reader, instancePath, RESOURCE_TYPE_NOT_A_RESOURCE_CODE, $"Data type '{name}' in property 'resourceType' is not a type of resource.", OO_Sev.Fatal, OO_Typ.Structure);
         internal static FhirJsonException UNKNOWN_PROPERTY_FOUND(ref Utf8JsonReader reader, string instancePath, string propName) => Initialize(ref reader, instancePath, UNKNOWN_PROPERTY_FOUND_CODE, $"Encountered unrecognized element '{propName}'.", OO_Sev.Error, OO_Typ.Structure); // this could be ignored, so isn't fatal?
         internal static FhirJsonException INCOMPATIBLE_SIMPLE_VALUE(ref Utf8JsonReader reader, string instancePath, string value, FhirJsonException? err) => Initialize(ref reader, instancePath, INCOMPATIBLE_SIMPLE_VALUE_CODE, $"Json primitive value does not match the expected type of the primitive property. Details: ({value})", OO_Sev.Fatal, OO_Typ.Value, err);
+        internal static FhirJsonException DUPLICATE_KEY(ref Utf8JsonReader reader, string instancePath, string key) => Initialize(ref reader, instancePath, DUPLICATE_KEYS_CODE, $"Encountered duplicate key \"{key}\"", OO_Sev.Fatal, OO_Typ.Structure);
 
         // ==========================================
         // Recoverable Errors

src/Hl7.Fhir.Support.Poco.Tests/NewPocoSerializers/FhirJsonDeserializationTests.cs

@@ -565,6 +565,36 @@ public void TestParseObjectPublicMethod()
                 // ok!
             }
         }
+
+        [TestMethod]
+        public void TestDuplicateIDs()
+        {
+            string jsonErrInput = "{\n" +
+                                  "\"resourceType\" : \"Patient\",\n" +
+                                  "\"active\" : true,\n" +
+                                  "\"active\" : false\n" +
+                                  "}";
+
+            var options = new JsonSerializerOptions().ForFhir(typeof(TestPatient).Assembly);
+
+            try
+            {
+                var actual = JsonSerializer.Deserialize<TestPatient>(jsonErrInput, options);
+                Assert.Fail("Should have encountered errors.");
+            }
+            catch (DeserializationFailedException dfe)
+            {
+                Console.WriteLine(dfe.Message);
+                var recoveredActual = JsonSerializer.Serialize(dfe.PartialResult, options);
+                Console.WriteLine(recoveredActual);
+
+                assertErrors(dfe.Exceptions, new string[]
+                {
+                    ERR.DUPLICATE_KEYS_CODE,
+                });
+            }
+
+        }
 
         [TestMethod]
         public void TestRecovery()