public async Task <(bool success, bool noValue, object model, Exception exception)> ReadAsync(FromBodyPropertyInputFormatterContext context, Func <Func <Stream, JsonSerializerOptions, Task>, Task> readRequestBody, Encoding encoding)
{
if (!string.Equals(_actionId, context.ActionId, StringComparison.Ordinal))
{
throw new InvalidOperationException("Invalid action '" + context.ActionId + "', initialize for action '" + _actionId + "'.");
}
if (!HasReadRequestBody)
{
HasReadRequestBody = true;
await readRequestBody(async (s, options) => {
_options = options;
int bufferSize = 0x4096;
var propertyData = new Dictionary <string, List <byte[]> >(StringComparer.Ordinal);
var readerOptions = new JsonReaderOptions {
AllowTrailingCommas = options.AllowTrailingCommas,
CommentHandling = options.ReadCommentHandling,
MaxDepth = options.MaxDepth
};
var readerState = new JsonReaderState(readerOptions);
var buffer = ArrayPool <byte> .Shared.Rent(bufferSize);
Memory <byte> memory = buffer.AsMemory(0, bufferSize);
int length;
int offset = 0;
string currentProperty = null;
int depth = 0;
DataBlockMode blockMode = DataBlockMode.Start;
bool handled = false;
bool finalBlock = false;
int consumed = 0;
try {
length = await s.ReadAsync(memory);
finalBlock = length == 0;
do
{
(handled, consumed) = HandleDataBlock(context, ref blockMode, ref depth, ref readerState, memory.Span.Slice(offset, length), finalBlock, ref currentProperty, propertyData);
offset += consumed;
if (!handled)
{
int bytesInBuffer = length - offset;
if (bytesInBuffer == 0)
{
// read more data
length = await s.ReadAsync(memory);
finalBlock = length == 0;
offset = 0;
}
else if ((uint)bytesInBuffer > ((uint)bufferSize / 2))
{
// expand buffer
bufferSize = (bufferSize < (int.MaxValue / 2)) ? bufferSize * 2 : int.MaxValue;
var buffer2 = ArrayPool <byte> .Shared.Rent(bufferSize);
// copy the unprocessed data
Buffer.BlockCopy(buffer, offset, buffer2, 0, bytesInBuffer);
// return previous buffer
ArrayPool <byte> .Shared.Return(buffer);
buffer = buffer2;
memory = buffer.AsMemory(0, bufferSize);
// read more data
length = await s.ReadAsync(memory.Slice(bytesInBuffer));
finalBlock = length == 0;
length += bytesInBuffer;
offset = 0;
}
else
{
Buffer.BlockCopy(buffer, offset, buffer, 0, bytesInBuffer);
// read more data
length = await s.ReadAsync(memory.Slice(bytesInBuffer));
finalBlock = length == 0;
length += bytesInBuffer;
offset = 0;
}
}
}while (!handled);
}
finally {
ArrayPool <byte> .Shared.Return(buffer);
}
foreach ((var key, var value) in propertyData)
{
_values.Add(key, value.SelectMany(z => z).ToArray());
}
});
}
if (!_keys.TryGetValue(context.FieldName, out var propertyType))
{
throw new InvalidOperationException("Unknown property '" + context.FieldName + "' requested.");
}
else if (_values.TryGetValue(context.FieldName, out var propertyData))
{
try {
var v = JsonSerializer.Deserialize(propertyData, propertyType, _options);
return(true, false, v, null);
}
catch (Exception ex) {
return(false, false, null, ex);
}
}
return(true, true, null, null);
}
private (bool handled, int consumed) HandleDataBlock(FromBodyPropertyInputFormatterContext context, ref DataBlockMode blockMode, ref int depth, ref JsonReaderState readerState, ReadOnlySpan <byte> data, bool finalBlock, ref string currentProperty, Dictionary <string, List <byte[]> > propertyData)
{
var jr = new Utf8JsonReader(data, finalBlock, readerState);
int start = 0;
while (jr.Read())
{
var jrt = jr.TokenType;
if (blockMode == DataBlockMode.Start)
{
if (jrt == JsonTokenType.StartObject)
{
blockMode = DataBlockMode.Body;
}
else if (jrt == JsonTokenType.Comment)
{
continue;
}
else
{
throw new Exception("Unexpected json token '" + jrt + "'.");
}
}
else if (blockMode == DataBlockMode.End)
{
if (jrt == JsonTokenType.Comment)
{
continue;
}
else
{
throw new Exception("Unexpected json token '" + jr.TokenType + "', expected end of object.");
}
}
else if (blockMode == DataBlockMode.Body)
{
if (jrt == JsonTokenType.EndObject)
{
blockMode = DataBlockMode.End;
}
else if (jrt == JsonTokenType.Comment)
{
continue;
}
else if (jrt == JsonTokenType.PropertyName)
{
currentProperty = jr.GetString();
if (propertyData.ContainsKey(currentProperty))
{
throw new Exception("Duplicate property: " + currentProperty);
}
propertyData.Add(currentProperty, new List <byte[]>());
start = checked ((int)jr.BytesConsumed);
blockMode = DataBlockMode.Property;
}
else
{
throw new Exception("Unexpected json token '" + jr.TokenType + "', expected property.");
}
}
else if (blockMode == DataBlockMode.Property)
{
if (IsValueToken(jrt))
{
propertyData[currentProperty].Add(data.Slice(start, checked ((int)jr.BytesConsumed) - start).ToArray());
blockMode = DataBlockMode.Body;
currentProperty = null;
start = checked ((int)jr.BytesConsumed);
}
else if (jrt == JsonTokenType.Comment)
{
continue;
}
else if (jrt == JsonTokenType.StartObject)
{
depth = jr.CurrentDepth;
blockMode = DataBlockMode.SkipObject;
}
else if (jrt == JsonTokenType.StartArray)
{
depth = jr.CurrentDepth;
blockMode = DataBlockMode.SkipArray;
}
else
{
throw new Exception("Unexpected json token '" + jr.TokenType + "', expected property value.");
}
}
else if (blockMode == DataBlockMode.SkipObject)
{
if (jrt == JsonTokenType.EndObject && jr.CurrentDepth == depth)
{
propertyData[currentProperty].Add(data.Slice(start, checked ((int)jr.BytesConsumed) - start).ToArray());
blockMode = DataBlockMode.Body;
currentProperty = null;
start = checked ((int)jr.BytesConsumed);
}
}
else if (blockMode == DataBlockMode.SkipArray)
{
if (jrt == JsonTokenType.EndArray && jr.CurrentDepth == depth)
{
propertyData[currentProperty].Add(data.Slice(start, checked ((int)jr.BytesConsumed) - start).ToArray());
blockMode = DataBlockMode.Body;
currentProperty = null;
start = checked ((int)jr.BytesConsumed);
}
}
else
{
throw new Exception("Unexpected state");
}
}
if (!jr.IsFinalBlock)
{
readerState = jr.CurrentState;
var consumed = checked ((int)jr.BytesConsumed);
if (consumed - start > 0 && (blockMode == DataBlockMode.SkipObject || blockMode == DataBlockMode.SkipArray))
{
propertyData[currentProperty].Add(data.Slice(start, consumed - start).ToArray());
}
return(false, consumed);
}
if (blockMode != DataBlockMode.End)
{
throw new Exception("More data expected");
}
return(true, 0);
}
/// <inheritdoc />
public async Task BindModelAsync(ModelBindingContext bindingContext)
{
if (bindingContext == null)
{
throw new ArgumentNullException(nameof(bindingContext));
}
AttemptingToBindModel(_logger, bindingContext);
// Special logic for body, treat the model name as string.Empty for the top level
// object, but allow an override via BinderModelName. The purpose of this is to try
// and be similar to the behavior for POCOs bound via traditional model binding.
string modelBindingKey;
if (bindingContext.IsTopLevelObject)
{
modelBindingKey = bindingContext.BinderModelName ?? string.Empty;
}
else
{
modelBindingKey = bindingContext.ModelName;
}
var httpContext = bindingContext.HttpContext;
var allowEmptyInputInModelBinding = _options?.AllowEmptyInputInBodyModelBinding == true;
var serviceProvider = httpContext.RequestServices;
var bodyModelBinderHelper = serviceProvider.GetService <IFromBodyPropertyModelBinderHelper>();
bodyModelBinderHelper.Initialize(bindingContext.ActionContext.ActionDescriptor.Id, bindingContext.ActionContext.ActionDescriptor.Parameters.Concat(bindingContext.ActionContext.ActionDescriptor.BoundProperties));
var formatterContext = new FromBodyPropertyInputFormatterContext(
httpContext,
modelBindingKey,
bindingContext.ModelState,
bindingContext.ModelMetadata,
_readerFactory,
allowEmptyInputInModelBinding,
bindingContext.ActionContext.ActionDescriptor.Id,
bindingContext.FieldName,
bodyModelBinderHelper);
var formatter = (IInputFormatter)null;
for (var i = 0; i < _formatters.Count; i++)
{
if (_formatters[i].CanRead(formatterContext))
{
formatter = _formatters[i];
InputFormatterSelected(_logger, formatter, formatterContext);
break;
}
else
{
InputFormatterRejected(_logger, _formatters[i], formatterContext);
}
}
if (formatter == null)
{
NoInputFormatterSelected(_logger, formatterContext);
var message = "FormatUnsupportedContentType: " + httpContext.Request.ContentType;
var exception = new UnsupportedContentTypeException(message);
bindingContext.ModelState.AddModelError(modelBindingKey, exception, bindingContext.ModelMetadata);
DoneAttemptingToBindModel(_logger, bindingContext);
return;
}
try {
var result = await formatter.ReadAsync(formatterContext);
if (result.HasError)
{
// Formatter encountered an error. Do not use the model it returned.
DoneAttemptingToBindModel(_logger, bindingContext);
return;
}
if (result.IsModelSet)
{
var model = result.Model;
bindingContext.Result = ModelBindingResult.Success(model);
}
else
{
// If the input formatter gives a "no value" result, that's always a model state error,
// because BodyModelBinder implicitly regards input as being required for model binding.
// If instead the input formatter wants to treat the input as optional, it must do so by
// returning InputFormatterResult.Success(defaultForModelType), because input formatters
// are responsible for choosing a default value for the model type.
var message = bindingContext
.ModelMetadata
.ModelBindingMessageProvider
.MissingRequestBodyRequiredValueAccessor();
bindingContext.ModelState.AddModelError(modelBindingKey, message);
}
}
catch (Exception exception) when(exception is InputFormatterException || ShouldHandleException(formatter))
{
bindingContext.ModelState.AddModelError(modelBindingKey, exception, bindingContext.ModelMetadata);
}
DoneAttemptingToBindModel(_logger, bindingContext);
}
