adding the Cbor Deserializer (#3877)

* adding the Cbor Deserializer

* Add error handling, validation on timestamp for negative value and adding size_t on beginStruct for definite length maps

* Optional returns to ShapeDeserializer

Author: pulimsr

src/aws-cpp-sdk-core/include/smithy/client/schema/CborShapeDeserializer.h

@@ -0,0 +1,46 @@
+#pragma once
+
+#include <aws/core/utils/memory/AWSMemory.h>
+#include <smithy/Smithy_EXPORTS.h>
+#include <smithy/client/schema/ShapeDeserializer.h>
+
+namespace smithy {
+namespace schema {
+
+class SMITHY_API CborShapeDeserializer final : public ShapeDeserializer {
+ public:
+  CborShapeDeserializer(const unsigned char* data, size_t length);
+  ~CborShapeDeserializer();
+
+  Aws::Crt::Optional<bool> ReadBoolean() override;
+  Aws::Crt::Optional<int> ReadInteger() override;
+  Aws::Crt::Optional<int64_t> ReadLong() override;
+  Aws::Crt::Optional<float> ReadFloat() override;
+  Aws::Crt::Optional<double> ReadDouble() override;
+  Aws::Crt::Optional<Aws::String> ReadString() override;
+  Aws::Crt::Optional<Aws::Utils::DateTime> ReadTimestamp() override;
+  Aws::Crt::Optional<Aws::Utils::ByteBuffer> ReadBlob() override;
+  Aws::Crt::Optional<int> ReadEnum() override;
+
+  size_t BeginStruct() override;
+  void EndStruct() override;
+
+  size_t BeginList() override;
+  void EndList() override;
+
+  size_t BeginMap() override;
+  void EndMap() override;
+
+  Aws::Crt::Optional<Aws::String> ReadKey() override;
+  bool IsBreak() override;
+  bool IsNull() override;
+  void ReadNull() override;
+  void SkipValue() override;
+
+ private:
+  class Impl;
+  Aws::UniquePtr<Impl> m_impl;
+};
+
+}  // namespace schema
+}  // namespace smithy

src/aws-cpp-sdk-core/include/smithy/client/schema/ShapeDeserializer.h

@@ -0,0 +1,45 @@
+#pragma once
+
+#include <aws/core/utils/Array.h>
+#include <aws/core/utils/DateTime.h>
+#include <aws/core/utils/memory/stl/AWSString.h>
+#include <aws/crt/Optional.h>
+#include <smithy/Smithy_EXPORTS.h>
+
+#include <cstdint>
+
+namespace smithy {
+namespace schema {
+
+class SMITHY_API ShapeDeserializer {
+ public:
+  virtual ~ShapeDeserializer() = default;
+
+  virtual Aws::Crt::Optional<bool> ReadBoolean() = 0;
+  virtual Aws::Crt::Optional<int> ReadInteger() = 0;
+  virtual Aws::Crt::Optional<int64_t> ReadLong() = 0;
+  virtual Aws::Crt::Optional<float> ReadFloat() = 0;
+  virtual Aws::Crt::Optional<double> ReadDouble() = 0;
+  virtual Aws::Crt::Optional<Aws::String> ReadString() = 0;
+  virtual Aws::Crt::Optional<Aws::Utils::DateTime> ReadTimestamp() = 0;
+  virtual Aws::Crt::Optional<Aws::Utils::ByteBuffer> ReadBlob() = 0;
+  virtual Aws::Crt::Optional<int> ReadEnum() = 0;
+
+  virtual size_t BeginStruct() = 0;
+  virtual void EndStruct() = 0;
+
+  virtual size_t BeginList() = 0;
+  virtual void EndList() = 0;
+
+  virtual size_t BeginMap() = 0;
+  virtual void EndMap() = 0;
+
+  virtual Aws::Crt::Optional<Aws::String> ReadKey() = 0;
+  virtual bool IsBreak() = 0;
+  virtual bool IsNull() = 0;
+  virtual void ReadNull() = 0;
+  virtual void SkipValue() = 0;
+};
+
+}  // namespace schema
+}  // namespace smithy

src/aws-cpp-sdk-core/source/smithy/client/schema/CborShapeDeserializer.cpp

@@ -0,0 +1,213 @@
+/**
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0.
+ */
+#include <aws/crt/cbor/Cbor.h>
+#include <smithy/client/schema/CborShapeDeserializer.h>
+
+using namespace smithy::schema;
+using namespace Aws::Utils;
+using namespace Aws::Crt::Cbor;
+
+class CborShapeDeserializer::Impl {
+ public:
+  Impl(const unsigned char* data, size_t length) : m_decoder(Aws::Crt::ByteCursorFromArray(data, length)) {}
+
+  Aws::Crt::Optional<bool> ReadBoolean() {
+    auto val = m_decoder.PopNextBooleanVal();
+    if (!val.has_value()) {
+      return {};
+    }
+    return val.value();
+  }
+
+  Aws::Crt::Optional<int> ReadInteger() {
+    auto val = ReadLong();
+    if (!val.has_value()) {
+      return {};
+    }
+    return static_cast<int>(val.value());
+  }
+
+  Aws::Crt::Optional<int64_t> ReadLong() {
+    auto type = m_decoder.PeekType();
+    if (!type.has_value()) {
+      return {};
+    }
+    if (*type == CborType::UInt) {
+      auto val = m_decoder.PopNextUnsignedIntVal();
+      if (!val.has_value()) {
+        return {};
+      }
+      return static_cast<int64_t>(val.value());
+    }
+    if (*type == CborType::NegInt) {
+      auto val = m_decoder.PopNextNegativeIntVal();
+      if (!val.has_value()) {
+        return {};
+      }
+      return static_cast<int64_t>(-(static_cast<int64_t>(val.value()) + 1));
+    }
+    return {};
+  }
+
+  Aws::Crt::Optional<float> ReadFloat() {
+    auto val = ReadDouble();
+    if (!val.has_value()) {
+      return {};
+    }
+    return static_cast<float>(val.value());
+  }
+
+  Aws::Crt::Optional<double> ReadDouble() {
+    auto type = m_decoder.PeekType();
+    if (!type.has_value()) {
+      return {};
+    }
+    if (*type == CborType::Float) {
+      auto val = m_decoder.PopNextFloatVal();
+      if (!val.has_value()) {
+        return {};
+      }
+      return val.value();
+    }
+    auto longVal = ReadLong();
+    if (!longVal.has_value()) {
+      return {};
+    }
+    return static_cast<double>(longVal.value());
+  }
+
+  Aws::Crt::Optional<Aws::String> ReadString() {
+    auto val = m_decoder.PopNextTextVal();
+    if (!val.has_value()) {
+      return {};
+    }
+    return Aws::String(reinterpret_cast<const char*>(val->ptr), val->len);
+  }
+
+  Aws::Crt::Optional<DateTime> ReadTimestamp() {
+    auto tag = m_decoder.PopNextTagVal();
+    if (!tag.has_value() || tag.value() != 1) {
+      return {};
+    }
+    auto type = m_decoder.PeekType();
+    if (!type.has_value()) {
+      return {};
+    }
+    if (*type == CborType::Float) {
+      auto val = m_decoder.PopNextFloatVal();
+      if (!val.has_value() || val.value() < 0.0) {
+        return {};
+      }
+      return DateTime(val.value());
+    }
+    if (*type == CborType::NegInt) {
+      return {};
+    }
+    auto val = ReadLong();
+    if (!val.has_value()) {
+      return {};
+    }
+    return DateTime(static_cast<double>(val.value()));
+  }
+
+  Aws::Crt::Optional<ByteBuffer> ReadBlob() {
+    auto val = m_decoder.PopNextBytesVal();
+    if (!val.has_value()) {
+      return {};
+    }
+    return ByteBuffer(val->ptr, val->len);
+  }
+
+  Aws::Crt::Optional<int> ReadEnum() { return ReadInteger(); }
+
+  size_t BeginStruct() {
+    auto type = m_decoder.PeekType();
+    if (type.has_value() && *type == CborType::IndefMapStart) {
+      m_decoder.ConsumeNextSingleElement();
+      return 0;
+    }
+    auto size = m_decoder.PopNextMapStart();
+    if (!size.has_value()) {
+      return 0;
+    }
+    return static_cast<size_t>(size.value());
+  }
+
+  void EndStruct() {}
+
+  size_t BeginList() {
+    auto type = m_decoder.PeekType();
+    if (type.has_value() && *type == CborType::IndefArrayStart) {
+      m_decoder.ConsumeNextSingleElement();
+      return 0;
+    }
+    auto size = m_decoder.PopNextArrayStart();
+    if (!size.has_value()) {
+      return 0;
+    }
+    return static_cast<size_t>(size.value());
+  }
+
+  void EndList() {}
+
+  size_t BeginMap() {
+    auto type = m_decoder.PeekType();
+    if (type.has_value() && *type == CborType::IndefMapStart) {
+      m_decoder.ConsumeNextSingleElement();
+      return 0;
+    }
+    auto size = m_decoder.PopNextMapStart();
+    if (!size.has_value()) {
+      return 0;
+    }
+    return static_cast<size_t>(size.value());
+  }
+
+  void EndMap() {}
+
+  Aws::Crt::Optional<Aws::String> ReadKey() { return ReadString(); }
+
+  bool IsBreak() {
+    auto type = m_decoder.PeekType();
+    return type.has_value() && *type == CborType::Break;
+  }
+
+  bool IsNull() {
+    auto type = m_decoder.PeekType();
+    return type.has_value() && *type == CborType::Null;
+  }
+
+  void ReadNull() { m_decoder.ConsumeNextSingleElement(); }
+
+  void SkipValue() { m_decoder.ConsumeNextWholeDataItem(); }
+
+ private:
+  CborDecoder m_decoder;
+};
+
+CborShapeDeserializer::CborShapeDeserializer(const unsigned char* data, size_t length)
+    : m_impl(Aws::MakeUnique<Impl>("CborShapeDeserializer", data, length)) {}
+CborShapeDeserializer::~CborShapeDeserializer() = default;
+
+Aws::Crt::Optional<bool> CborShapeDeserializer::ReadBoolean() { return m_impl->ReadBoolean(); }
+Aws::Crt::Optional<int> CborShapeDeserializer::ReadInteger() { return m_impl->ReadInteger(); }
+Aws::Crt::Optional<int64_t> CborShapeDeserializer::ReadLong() { return m_impl->ReadLong(); }
+Aws::Crt::Optional<float> CborShapeDeserializer::ReadFloat() { return m_impl->ReadFloat(); }
+Aws::Crt::Optional<double> CborShapeDeserializer::ReadDouble() { return m_impl->ReadDouble(); }
+Aws::Crt::Optional<Aws::String> CborShapeDeserializer::ReadString() { return m_impl->ReadString(); }
+Aws::Crt::Optional<DateTime> CborShapeDeserializer::ReadTimestamp() { return m_impl->ReadTimestamp(); }
+Aws::Crt::Optional<ByteBuffer> CborShapeDeserializer::ReadBlob() { return m_impl->ReadBlob(); }
+Aws::Crt::Optional<int> CborShapeDeserializer::ReadEnum() { return m_impl->ReadEnum(); }
+size_t CborShapeDeserializer::BeginStruct() { return m_impl->BeginStruct(); }
+void CborShapeDeserializer::EndStruct() { m_impl->EndStruct(); }
+size_t CborShapeDeserializer::BeginList() { return m_impl->BeginList(); }
+void CborShapeDeserializer::EndList() { m_impl->EndList(); }
+size_t CborShapeDeserializer::BeginMap() { return m_impl->BeginMap(); }
+void CborShapeDeserializer::EndMap() { m_impl->EndMap(); }
+Aws::Crt::Optional<Aws::String> CborShapeDeserializer::ReadKey() { return m_impl->ReadKey(); }
+bool CborShapeDeserializer::IsBreak() { return m_impl->IsBreak(); }
+bool CborShapeDeserializer::IsNull() { return m_impl->IsNull(); }
+void CborShapeDeserializer::ReadNull() { m_impl->ReadNull(); }
+void CborShapeDeserializer::SkipValue() { m_impl->SkipValue(); }