private static void ValidateMultipartRequest(HttpRequest request)
{
if (!MultipartRequest.IsMultipartContentType(request.ContentType))
{
throw new InvalidOperationException($"Expected a multipart request, but got {request.ContentType}");
}
}
public static async Task <FormValueProvider> StreamFile(this HttpRequest request, Stream targetStream)
{
ValidateMultipartRequest(request);
// Used to accumulate all the form url encoded key value pairs in the
// request.
var formAccumulator = new KeyValueAccumulator();
var boundary = MultipartRequest.GetBoundary(MediaTypeHeaderValue.Parse(request.ContentType), defaultFormOptions.MultipartBoundaryLengthLimit);
var reader = new MultipartReader(boundary, request.Body);
var section = await reader.ReadNextSectionAsync();
while (section != null)
{
var hasContentDispositionHeader = ContentDispositionHeaderValue
.TryParse(section.ContentDisposition, out ContentDispositionHeaderValue contentDisposition);
if (hasContentDispositionHeader)
{
if (MultipartRequest.HasFileContentDisposition(contentDisposition))
{
formAccumulator.Append("FileContentType", section.ContentType);
formAccumulator.Append("FileName", contentDisposition.FileName.Value);
await section.Body.CopyToAsync(targetStream);
targetStream.Seek(0, SeekOrigin.Begin);
}
else
{
if (MultipartRequest.HasFormDataContentDisposition(contentDisposition))
{
// Content-Disposition: form-data; name="key"
//
// value
// Do not limit the key name length here because the
// multipart headers length limit is already in effect.
var key = HeaderUtilities.RemoveQuotes(contentDisposition.Name);
var encoding = GetEncoding(section);
using (var streamReader = new StreamReader(
section.Body,
encoding,
detectEncodingFromByteOrderMarks: true,
bufferSize: 1024,
leaveOpen: true))
{
// The value length limit is enforced by MultipartBodyLengthLimit
var value = await ReadValue(streamReader);
formAccumulator.Append(key.Value, value); // For .NET Core <2.0 remove ".Value" from key
CheckIfFormKeyLimitExceeded(formAccumulator);
}
}
}
}
// Drains any remaining section body that has not been consumed and
// reads the headers for the next section.
section = await reader.ReadNextSectionAsync();
}
// Bind form data to a model
var formValueProvider = new FormValueProvider(
BindingSource.Form,
new FormCollection(formAccumulator.GetResults()),
CultureInfo.CurrentCulture);
return(formValueProvider);
}
