Improved delayed parsing for base64 and code<t>

src/Hl7.Fhir.Base/Model/Base64Binary.cs

@@ -29,7 +29,11 @@ POSSIBILITY OF SUCH DAMAGE.
 */
 
 using Hl7.Fhir.ElementModel.Types;
+using Hl7.Fhir.Validation;
 using System;
+using System.Collections.Generic;
+using System.ComponentModel.DataAnnotations;
+using System.Linq;
 using P=Hl7.Fhir.ElementModel.Types;
 
 #nullable enable
@@ -38,20 +42,87 @@ namespace Hl7.Fhir.Model;
 
 public partial class Base64Binary
 {
+    /// <summary>
+    /// Constructs a Base64Binary instance from a string of base64-encoded data.
+    /// </summary>
     public static Base64Binary FromBase64String(string base64Data) =>
-        new(Convert.FromBase64String(base64Data));
+        new() { ObjectValue = base64Data };
 
+    /// <summary>
+    /// Constructs a Base64Binary instance from a string of human-readable text.
+    /// </summary>
+    /// <param name="text"></param>
+    /// <returns></returns>
     public static Base64Binary FromText(string text) =>
         new(System.Text.Encoding.UTF8.GetBytes(text));
 
+    [NonSerialized]  // To prevent binary serialization from serializing this field
+    private byte[]? _parsedValue = null;
+
+    protected override void OnObjectValueChanged()
+    {
+        _parsedValue = null;
+        base.OnObjectValueChanged();
+    }
+
+    public partial byte[]? Value
+    {
+        get
+        {
+            if (_parsedValue is null && ObjectValue is not null)
+            {
+                if(ObjectValue is string base64data)
+                    _parsedValue = Convert.FromBase64String(base64data);
+                else
+                {
+                    throw new InvalidCastException($"Cannot convert value '{ObjectValue}' of type {ObjectValue.GetType()} to a byte array.");
+                }
+            }
+
+            return _parsedValue;
+        }
+
+        set
+        {
+            ObjectValue = value is null ? null : Convert.ToBase64String(value);
+            OnPropertyChanged("Value");
+        }
+    }
+
+    public override IEnumerable<ValidationResult> Validate(ValidationContext validationContext)
+    {
+        var baseResults = base.Validate(validationContext);
+
+        if (HasValidValue())
+            return baseResults;
+
+        var result = CodedValidationException.INVALID_BASE64_VALUE(validationContext, ObjectValue).AsResult(validationContext);
+        return baseResults.Append(result);
+    }
+
+    public bool HasValidValue()
+    {
+        try
+        {
+            // There is no TryDecode(), so this is all we can do.
+            _ = Value;
+            return true;
+        }
+        catch
+        {
+            return false;
+        }
+    }
+
     /// <summary>
     /// Checks whether the given literal is correctly formatted.
     /// </summary>
     public static bool IsValidValue(string value)
     {
         try
         {
-            _ = Convert.FromBase64String(value);
+            var b64 = FromBase64String(value);
+            _ = b64.Value;  // triggers b64 decoding
             return true;
         }
         catch

src/Hl7.Fhir.Base/Model/CodeOfT.cs

@@ -68,14 +68,32 @@ public Code(T? value)
         Value = value;
     }
 
+    [NonSerialized]  // To prevent binary serialization from serializing this field
+    private T? _parsedValue = null;
+
+    protected override void OnObjectValueChanged()
+    {
+        _parsedValue = null;
+        base.OnObjectValueChanged();
+    }
+
     // Primitive value of element
     [FhirElement("value", IsPrimitiveValue = true, XmlSerialization = XmlRepresentation.XmlAttr, InSummary = true, Order = 30)]
     [DataMember]
     new public T? Value
     {
-        get => TryParseObjectValue(out var value)
-            ? value
-            : throw new InvalidCastException($"Value '{ObjectValue}' cannot be cast to a member of enumeration {typeof(T).Name}.");
+        get
+        {
+            if (_parsedValue is null && ObjectValue is not null)
+            {
+                if(TryParseObjectValue(out var parsed))
+                    _parsedValue = parsed;
+                else
+                    throw new InvalidCastException($"Cannot convert value '{ObjectValue}' of type {ObjectValue.GetType()} to an enum of type {typeof(T)}.");
+            }
+
+            return _parsedValue;
+        }
         set
         {
             ObjectValue = value?.GetLiteral();
@@ -92,7 +110,8 @@ internal bool TryParseObjectValue(out T? value)
             value = parsed;
             return true;
         }
-        else return ObjectValue is null;
+
+        return ObjectValue is null;
     }
 
     /// <inheritdoc />

src/Hl7.Fhir.Base/Model/Date.cs

@@ -79,7 +79,7 @@ public bool TryToSystemDate([NotNullWhen(true)] out P.Date? date)
     {
         if (_parsedValue is null)
         {
-            if (Value is not null && !(P.Date.TryParse(Value, out _parsedValue) && !_parsedValue!.HasOffset))
+            if (Value is null || !(P.Date.TryParse(Value, out _parsedValue) && !_parsedValue!.HasOffset))
                 _parsedValue = INVALID_VALUE;
         }
 
@@ -124,11 +124,7 @@ protected override void OnObjectValueChanged()
     /// <returns>A DateTimeOffset filled out to midnight, january 1 (UTC) in case of a partial date.</returns>
     public DateTimeOffset ToDateTimeOffset()
     {
-        if (Value == null) throw new InvalidOperationException("Date's value is null.");
-
-        // TryToDate() will convert partial date/times by filling out to midnight/january 1 UTC
-        if (!TryToSystemDate(out var dt))
-            throw new FormatException($"Date '{Value}' was not recognized as a valid datetime.");
+        var dt = ToSystemDate();
 
         // Since Value is not null and the parsed value is valid, dto will not be null
         return dt.ToDateTimeOffset(TimeSpan.Zero);
@@ -140,7 +136,7 @@ public DateTimeOffset ToDateTimeOffset()
     /// <returns>True if the value of the Fhir Date is not null and can be parsed as a DateTimeOffset, false otherwise.</returns>
     public bool TryToDateTimeOffset(out DateTimeOffset dto)
     {
-        if (Value is not null && TryToSystemDate(out var dt))
+        if (TryToSystemDate(out var dt))
         {
             dto = dt.ToDateTimeOffset(TimeSpan.Zero);
             return true;

src/Hl7.Fhir.Base/Model/FhirDateTime.cs

@@ -102,7 +102,7 @@ public bool TryToSystemDateTime([NotNullWhen(true)] out P.DateTime? dateTime)
     {
         if (_parsedValue is null)
         {
-            if (Value is not null && !P.DateTime.TryParse(Value, out _parsedValue))
+            if (Value is null || !P.DateTime.TryParse(Value, out _parsedValue))
                 _parsedValue = INVALID_VALUE;
         }
 
@@ -111,11 +111,9 @@ public bool TryToSystemDateTime([NotNullWhen(true)] out P.DateTime? dateTime)
             dateTime = null;
             return false;
         }
-        else
-        {
-            dateTime = _parsedValue!;
-            return true;
-        }
+
+        dateTime = _parsedValue!;
+        return true;
 
         bool hasInvalidParsedValue() => ReferenceEquals(_parsedValue, INVALID_VALUE);
     }
@@ -154,11 +152,7 @@ protected override void OnObjectValueChanged()
     /// effect on this, this merely converts the given Fhir datetime to the desired timezone</returns>
     public DateTimeOffset ToDateTimeOffset(TimeSpan zone)
     {
-        if (Value == null) throw new InvalidOperationException("FhirDateTime's value is null.");
-
-        // TryToDateTime() will convert partial date/times by filling out to midnight/january 1 UTC.
-        if (!TryToSystemDateTime(out var dt))
-            throw new FormatException($"DateTime '{Value}' was not recognized as a valid datetime.");
+        var dt = ToSystemDateTime();
 
         // Since Value is not null and the parsed value is valid, dto will not be null
         return dt.ToDateTimeOffset(TimeSpan.Zero).ToOffset(zone);
@@ -171,7 +165,7 @@ public DateTimeOffset ToDateTimeOffset(TimeSpan zone)
     /// specified timezone, false otherwise.</returns>
     public bool TryToDateTimeOffset(out DateTimeOffset dto)
     {
-        if (Value is not null && TryToSystemDateTime(out var dt) && dt.Offset is not null)
+        if (TryToSystemDateTime(out var dt) && dt.Offset is not null)
         {
             dto = dt.ToDateTimeOffset(dt.Offset.Value);
             return true;
@@ -189,7 +183,7 @@ public bool TryToDateTimeOffset(out DateTimeOffset dto)
     /// <returns>True if the value of the FhirDateTime is not null and can be parsed as a DateTimeOffset, false otherwise.</returns>
     public bool TryToDateTimeOffset(TimeSpan defaultOffset, out DateTimeOffset dto)
     {
-        if (Value is not null && TryToSystemDateTime(out var dt))
+        if (TryToSystemDateTime(out var dt))
         {
             dto = dt.ToDateTimeOffset(defaultOffset);
             return true;

src/Hl7.Fhir.Base/Model/Generated/Base64Binary.cs

@@ -74,11 +74,7 @@ public Base64Binary(): this((byte[])null) {}
     [FhirElement("value", IsPrimitiveValue=true, XmlSerialization=XmlRepresentation.XmlAttr, InSummary=true, Order=30)]
     [DeclaredType(Type = typeof(SystemPrimitive.String))]
     [DataMember]
-    public byte[] Value
-    {
-      get { return (byte[])ObjectValue; }
-      set { ObjectValue = value; OnPropertyChanged("Value"); }
-    }
+    public partial byte[] Value { get; set; }
 
     protected internal override Base DeepCopyInternal()
     {

src/Hl7.Fhir.Base/Model/Generated/Integer64.cs

@@ -74,19 +74,7 @@ public Integer64(): this((long?)null) {}
     [FhirElement("value", IsPrimitiveValue=true, XmlSerialization=XmlRepresentation.XmlAttr, InSummary=true, Order=30)]
     [DeclaredType(Type = typeof(SystemPrimitive.Long))]
     [DataMember]
-    public long? Value
-    {
-      get
-{
-    return ObjectValue switch
-    {
-        null => null,
-        long l => l,
-        _ => Convert.ToInt64(ObjectValue)
-    };
-}
-      set { ObjectValue = value; OnPropertyChanged("Value"); }
-    }
+    public partial long? Value { get; set; }
 
     protected internal override Base DeepCopyInternal()
     {

src/Hl7.Fhir.Base/Model/Generated/XHtml.cs

@@ -81,8 +81,9 @@ protected internal override Base DeepCopyInternal()
       CopyToInternal(instance);
       return instance;
     }
+
   }
 
 }
 
-// end of file
+// end of file

src/Hl7.Fhir.Base/Model/Integer64.cs

@@ -37,6 +37,20 @@ namespace Hl7.Fhir.Model;
 
 public partial class Integer64
 {
+    public partial long? Value
+    {
+        get
+        {
+            return ObjectValue switch
+            {
+                null => null,
+                long l => l,
+                _ => Convert.ToInt64(ObjectValue)
+            };
+        }
+        set { ObjectValue = value; OnPropertyChanged("Value"); }
+    }
+
     /// <summary>
     /// Checks whether the given literal is correctly formatted.
     /// </summary>

src/Hl7.Fhir.Base/Model/Time.cs

@@ -72,7 +72,7 @@ public bool TryToSystemTime([NotNullWhen(true)] out P.Time? time)
     {
         if (_parsedValue is null)
         {
-            if (Value is not null && !P.Time.TryParse(Value, out _parsedValue))
+            if (Value is null || !P.Time.TryParse(Value, out _parsedValue))
                 _parsedValue = INVALID_VALUE;
         }
 
@@ -81,11 +81,9 @@ public bool TryToSystemTime([NotNullWhen(true)] out P.Time? time)
             time = null;
             return false;
         }
-        else
-        {
-            time = _parsedValue!;
-            return true;
-        }
+
+        time = _parsedValue!;
+        return true;
 
         bool hasInvalidParsedValue() => ReferenceEquals(_parsedValue, INVALID_VALUE);
     }
@@ -129,16 +127,14 @@ public TimeSpan ToTimeSpan() =>
     /// <returns>True if the value of the Fhir Time is not null and can be parsed as a Time without an offset, false otherwise.</returns>
     public bool TryToTimeSpan(out TimeSpan dto)
     {
-        if (Value is not null && TryToSystemTime(out var dt) && !dt.HasOffset)
+        if (TryToSystemTime(out var dt) && !dt.HasOffset)
         {
             dto = dt.ToTimeSpan();
             return true;
         }
-        else
-        {
-            dto = TimeSpan.Zero;
-            return false;
-        }
+
+        dto = TimeSpan.Zero;
+        return false;
     }
 
     /// <summary>

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

@@ -720,8 +720,7 @@ FhirJsonPocoDeserializerState state
                 JsonTokenType.Null => new(null, ERR.EXPECTED_PRIMITIVE_NOT_NULL(ref reader, pathStack.GetInstancePath())),
                 JsonTokenType.String when string.IsNullOrEmpty(reader.GetString()) => new(reader.GetString(), ERR.PROPERTY_MAY_NOT_BE_EMPTY(ref reader, pathStack.GetInstancePath())),
                 JsonTokenType.String when implementingType == typeof(string) => new(reader.GetString(), null),
-                JsonTokenType.String when implementingType == typeof(byte[]) =>
-                                !Settings.DisableBase64Decoding ? readBase64(ref reader, pathStack) : new(reader.GetString(), null),
+                JsonTokenType.String when implementingType == typeof(byte[]) => new(reader.GetString(), null),
                 JsonTokenType.String when implementingType == typeof(DateTimeOffset) => readDateTimeOffset(ref reader, pathStack),
                 JsonTokenType.String when implementingType.IsEnum => new(reader.GetString(), null),
                 JsonTokenType.String when implementingType == typeof(long) => readLong(ref reader, fhirType, pathStack),
@@ -749,11 +748,6 @@ FhirJsonPocoDeserializerState state
 
             return result;
 
-            static (object?, FhirJsonException?) readBase64(ref Utf8JsonReader reader, PathStack pathStack) =>
-                reader.TryGetBytesFromBase64(out var bytesValue) ?
-                    new(bytesValue, null) :
-                    new(reader.GetString(), ERR.INCORRECT_BASE64_DATA(ref reader, pathStack.GetInstancePath()));
-
             static (object?, FhirJsonException?) readDateTimeOffset(ref Utf8JsonReader reader, PathStack pathStack)
             {
                 var contents = reader.GetString()!;