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/**
* Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: Apache-2.0.
*/
#include <aws/common/common.h>
#include <aws/core/utils/event/EventHeader.h>
#include <aws/core/utils/event/EventMessage.h>
#include <aws/core/utils/event/EventStreamDecoder.h>
#include <aws/core/utils/logging/LogMacros.h>
#include <aws/core/utils/UnreferencedParam.h>
#include <aws/core/utils/memory/AWSMemory.h>
namespace Aws
{
namespace Utils
{
namespace Event
{
static const char EVENT_STREAM_DECODER_CLASS_TAG[] = "Aws::Utils::Event::EventStreamDecoder";
EventStreamDecoder::EventStreamDecoder(EventStreamHandler* handler) : m_eventStreamHandler(handler)
{
aws_event_stream_streaming_decoder_init(&m_decoder,
get_aws_allocator(),
onPayloadSegment,
onPreludeReceived,
onHeaderReceived,
onError,
(void*)handler);
}
EventStreamDecoder::~EventStreamDecoder()
{
aws_event_stream_streaming_decoder_clean_up(&m_decoder);
}
void EventStreamDecoder::Pump(const ByteBuffer& data)
{
Pump(data, data.GetLength());
}
void EventStreamDecoder::Pump(const ByteBuffer& data, size_t length)
{
aws_byte_buf dataBuf = aws_byte_buf_from_array(static_cast<uint8_t*>(data.GetUnderlyingData()), length);
aws_event_stream_streaming_decoder_pump(&m_decoder, &dataBuf);
}
void EventStreamDecoder::Reset()
{
m_eventStreamHandler->Reset();
}
void EventStreamDecoder::ResetEventStreamHandler(EventStreamHandler* handler)
{
aws_event_stream_streaming_decoder_init(&m_decoder, get_aws_allocator(),
onPayloadSegment,
onPreludeReceived,
onHeaderReceived,
onError,
reinterpret_cast<void *>(handler));
}
void EventStreamDecoder::onPayloadSegment(
aws_event_stream_streaming_decoder* decoder,
aws_byte_buf* payload,
int8_t isFinalSegment,
void* context)
{
AWS_UNREFERENCED_PARAM(decoder);
auto handler = static_cast<EventStreamHandler*>(context);
assert(handler);
if (!handler)
{
AWS_LOGSTREAM_ERROR(EVENT_STREAM_DECODER_CLASS_TAG, "Payload received, but handler is null.");
return;
}
handler->WriteMessageEventPayload(static_cast<unsigned char*>(payload->buffer), payload->len);
// Complete payload received
if (isFinalSegment == 1)
{
assert(handler->IsMessageCompleted());
handler->OnEvent();
handler->Reset();
}
}
void EventStreamDecoder::onPreludeReceived(
aws_event_stream_streaming_decoder* decoder,
aws_event_stream_message_prelude* prelude,
void* context)
{
AWS_UNREFERENCED_PARAM(decoder);
auto handler = static_cast<EventStreamHandler*>(context);
handler->Reset();
//Encounter internal error in prelude received.
//This error will be handled by OnError callback function later.
if (prelude->total_len < prelude->headers_len + 16)
{
return;
}
handler->SetMessageMetadata(prelude->total_len, prelude->headers_len,
prelude->total_len - prelude->headers_len - 4/*total byte-length*/ - 4/*headers byte-length*/ - 4/*prelude crc*/ - 4/*message crc*/);
AWS_LOGSTREAM_TRACE(EVENT_STREAM_DECODER_CLASS_TAG, "Message received, the expected length of the message is: " << prelude->total_len <<
" bytes, and the expected length of the header is: " << prelude->headers_len << " bytes");
//Handle empty message
//if (handler->m_message.GetHeadersLength() == 0 && handler->m_message.GetPayloadLength() == 0)
if (handler->IsMessageCompleted())
{
handler->OnEvent();
handler->Reset();
}
}
void EventStreamDecoder::onHeaderReceived(
aws_event_stream_streaming_decoder* decoder,
aws_event_stream_message_prelude* prelude,
aws_event_stream_header_value_pair* header,
void* context)
{
AWS_UNREFERENCED_PARAM(decoder);
AWS_UNREFERENCED_PARAM(prelude);
auto handler = static_cast<EventStreamHandler*>(context);
assert(handler);
if (!handler)
{
AWS_LOGSTREAM_ERROR(EVENT_STREAM_DECODER_CLASS_TAG, "Header received, but handler is null.");
return;
}
// The length of a header = 1 byte (to represent the length of header name) + length of header name + 1 byte (to represent header type)
// + 2 bytes (to represent length of header value) + length of header value
handler->InsertMessageEventHeader(Aws::String(header->header_name, header->header_name_len),
1 + header->header_name_len + 1 + 2 + header->header_value_len, EventHeaderValue(header));
// Handle messages only have headers, but without payload.
//if (handler->m_message.GetHeadersLength() == handler->m_headersBytesReceived() && handler->m_message.GetPayloadLength() == 0)
if (handler->IsMessageCompleted())
{
handler->OnEvent();
handler->Reset();
}
}
void EventStreamDecoder::onError(
aws_event_stream_streaming_decoder* decoder,
aws_event_stream_message_prelude* prelude,
int error_code,
const char* message,
void* context)
{
AWS_UNREFERENCED_PARAM(decoder);
AWS_UNREFERENCED_PARAM(prelude);
auto handler = static_cast<EventStreamHandler*>(context);
handler->SetFailure();
handler->SetInternalError(error_code);
handler->WriteMessageEventPayload(reinterpret_cast<const unsigned char*>(message), strlen(message));
handler->OnEvent();
}
} // namespace Event
} // namespace Utils
} // namespace Aws
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