let azure core provide json interface (#1004)

* let azure core provide json interface

cmake-modules/add_nlohmann_json.cmake

@@ -0,0 +1,27 @@
+# Copyright (c) Microsoft Corporation. All rights reserved.
+# SPDX-License-Identifier: MIT
+#
+# Azure Core can expose the Nlohmann Json header by fetching a release version and including the header to the include path.
+# 
+# Azure Core will try to find the json header first. This is for an application that is already using Nlohmann header.
+# When it is not found it, Azure Core will fetch it.
+
+# Storage requires 3.6.0 version for using `contains` feature
+# Using QUIET to avoid warning message if lib is not found
+find_package(nlohmann_json 3.6.0 EXACT QUIET)
+if (NOT nlohmann_json_FOUND)
+
+    include(FetchContent)
+
+    # release code only. This save us from getting the entire nlohmann source code.
+    FetchContent_Declare(json
+        GIT_REPOSITORY https://github.com/ArthurSonzogni/nlohmann_json_cmake_fetchcontent
+        GIT_TAG v3.8.0)
+
+    FetchContent_GetProperties(json)
+    if (NOT json_POPULATED)
+      FetchContent_Populate(json)
+      add_subdirectory(${json_SOURCE_DIR} ${json_BINARY_DIR} EXCLUDE_FROM_ALL)
+    endif()
+
+endif()

sdk/core/azure-core/CMakeLists.txt

@@ -31,6 +31,9 @@ endif()
 # CodeCoverage will validate requirements
 include(CodeCoverage)
 
+# nlohmann JSON
+include(add_nlohmann_json)
+
 add_library (
   ${TARGET_NAME}
   src/context.cpp
@@ -63,6 +66,7 @@ create_code_coverage(core ${TARGET_NAME} "${TARGET_NAME}-test")
 
 target_include_directories(${TARGET_NAME} PUBLIC ${CURL_INCLUDE_DIRS})
 target_link_libraries(${TARGET_NAME} PRIVATE CURL::libcurl Threads::Threads)
+target_link_libraries(${TARGET_NAME} INTERFACE nlohmann_json::nlohmann_json)
 
 get_az_version("${CMAKE_CURRENT_SOURCE_DIR}/inc/azure/core/version.hpp")
 generate_documentation(azure-core ${AZ_LIBRARY_VERSION})

sdk/core/azure-core/test/ut/CMakeLists.txt

@@ -32,6 +32,7 @@ add_executable (
      curl_session_test.cpp
      datetime.cpp
      http.cpp
+     json.cpp
      logging.cpp
      main.cpp
      nullable.cpp

sdk/core/azure-core/test/ut/json.cpp

@@ -0,0 +1,17 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+#include "gtest/gtest.h"
+#include <nlohmann/json.hpp>
+
+using json = nlohmann::json;
+
+// Just a simple test to ensure that Azure Core is bringing nlohmann header
+TEST(Json, create)
+{
+  json j;
+  j["pi"] = 3.141;
+  std::string expected("{\"pi\":3.141}");
+
+  EXPECT_EQ(expected, j.dump());
+}

sdk/core/azure-core/test/ut/transport_adapter_curl.cpp

@@ -40,11 +40,13 @@ namespace Azure { namespace Core { namespace Test {
     Azure::Core::Http::CurlConnectionPool::ClearIndex();
 
     auto threadRoutine = [&]() {
+      using namespace std::chrono_literals;
       auto request = Azure::Core::Http::Request(Azure::Core::Http::HttpMethod::Get, host);
       auto response = m_pipeline->Send(Azure::Core::GetApplicationContext(), request);
       checkResponseCode(response->GetStatusCode());
       auto expectedResponseBodySize = std::stoull(response->GetHeaders().at("content-length"));
       CheckBodyFromBuffer(*response, expectedResponseBodySize);
+      std::this_thread::sleep_for(1s);
     };
 
     std::thread t1(threadRoutine);

sdk/storage/azure-storage-common/CMakeLists.txt

@@ -10,7 +10,6 @@ set(AZURE_STORAGE_COMMON_HEADER
     inc/azure/storage/common/constants.hpp
     inc/azure/storage/common/crypt.hpp
     inc/azure/storage/common/file_io.hpp
-    inc/azure/storage/common/json.hpp
     inc/azure/storage/common/reliable_stream.hpp
     inc/azure/storage/common/shared_key_policy.hpp
     inc/azure/storage/common/storage_common.hpp

sdk/storage/azure-storage-common/src/storage_exception.cpp

@@ -5,10 +5,10 @@
 
 #include "azure/core/http/policy.hpp"
 #include "azure/storage/common/constants.hpp"
-#include "azure/storage/common/json.hpp"
 #include "azure/storage/common/storage_common.hpp"
 #include "azure/storage/common/xml_wrapper.hpp"
 
+#include <nlohmann/json.hpp>
 #include <type_traits>
 
 namespace Azure { namespace Storage {

sdk/storage/azure-storage-files-datalake/inc/azure/storage/files/datalake/protocol/datalake_rest_client.hpp

@@ -9,7 +9,6 @@
 #include "azure/core/nullable.hpp"
 #include "azure/core/response.hpp"
 #include "azure/storage/common/crypt.hpp"
-#include "azure/storage/common/json.hpp"
 #include "azure/storage/common/storage_common.hpp"
 #include "azure/storage/common/storage_exception.hpp"
 
@@ -17,6 +16,7 @@
 #include <iostream>
 #include <map>
 #include <memory>
+#include <nlohmann/json.hpp>
 #include <stdexcept>
 #include <string>
 #include <vector>

sdk/storage/azure-storage-files-shares/inc/azure/storage/files/shares/protocol/share_rest_client.hpp

@@ -10,11 +10,11 @@
 #include "azure/core/response.hpp"
 #include "azure/core/strings.hpp"
 #include "azure/storage/common/crypt.hpp"
-#include "azure/storage/common/json.hpp"
 #include "azure/storage/common/storage_common.hpp"
 #include "azure/storage/common/storage_exception.hpp"
 #include "azure/storage/common/xml_wrapper.hpp"
 
+#include <nlohmann/json.hpp>
 #include <functional>
 #include <iostream>
 #include <map>