Updated v2 fork with latest libraries, bug fixes and vcpkg manifest integration

[sukesh-ak]

I have fixed bugs and have an updated fork of v2 here

https://github.com/Zdhaa/cppkiteconnect/commits/v2

I have tested on Ubuntu for now.
It should work on all platforms as well viz (Windows, Linux & Mac).

Completed tasks

• Removed external dependency of submodules
• Added vcpkg as submodule with manifest mode ( vcpkg.json )
• Upgraded all the dependencies to latest version - fmt,picosha2,rapidjson,cpp-httplib
• Fixed few bugs connected to fmt upgrade to fmt 9.x
• Updated Kite related header files with proper header file path for vcpkg changes
• Updated httplib error code to strings which was marked as TODO
• Updated CMakeLists.txt with find_package for components coming from vcpkg.

Have added vcpkg as cmake toolchain here in CMakeLists.txt

Clone, compile and test

# Clone recursive v2 branch
$ git clone --recursive https://github.com/Zdhaa/cppkiteconnect -b v2

# pre-compiled (Ubuntu x64) libuWS.a is in uWS folder - since this is an older version with client support
$ cmake . -B build -DBUILD_EXAMPLES=On -DUWS_LIB=uWS/libuWS.a && cmake --build build

Here is the content of vcpkg.json

{
    "name": "cppkiteconnect",
    "version-string": "2.0.0",
    "homepage": "https://github.com/zerodha/cppkiteconnect",
    "description": "C++ Kite Connect API library / SDK",
    "dependencies": [
      "fmt",
      "cpp-httplib",
      "picosha2",
      "rapidjson",
      "zlib",
      "gtest",
      "libuv",
      "openssl"
    ]
  }

Will send PR if its ok.

[bhumitattarde]

Hello, thank you for your work! Can you please open a PR? Let's discuss the changes there.

[sukesh-ak]

@bhumitattarde Will send the PR.

For updating the C++ standard to 20 (now it's 17), there are 2 more bugs explained below.

CXX 20 is required since chrono and fmt from CXX 20 onwards supports dates and there are quite a few useful functions for use with this SDK.

std::chrono::sys_days month_last_Thursday(unsigned m, int y)
{
     return {year{y} / month{m} / Thursday[last]};
}

Compile Errors

In file included from /home/cuteghost/dev/cppkiteconnect/include/kitepp/kite/kite.hpp:28,
                 from /home/cuteghost/dev/cppkiteconnect/include/kitepp.hpp:39,
                 from /home/cuteghost/dev/cppkiteconnect/examples/example1.cpp:26:
/home/cuteghost/dev/cppkiteconnect/include/kitepp/kite/api.hpp: In member function ‘std::string kiteconnect::kite::loginURL() const’:
/home/cuteghost/dev/cppkiteconnect/include/kitepp/kite/api.hpp:45:15: error: ‘this’ is not a constant expression
   45 |     return FMT(loginUrlFmt, "api_key"_a = key);
In file included from /home/cuteghost/dev/cppkiteconnect/include/kitepp/ticker.hpp:28,
                 from /home/cuteghost/dev/cppkiteconnect/include/kitepp.hpp:41,
                 from /home/cuteghost/dev/cppkiteconnect/examples/example1.cpp:26:
/home/cuteghost/dev/cppkiteconnect/include/kitepp/ticker/internal.hpp: In member function ‘void kiteconnect::ticker::connectInternal()’:
/home/cuteghost/dev/cppkiteconnect/include/kitepp/ticker/internal.hpp:170:20: error: ‘this’ is not a constant expression
  170 |     hub.connect(FMT(connectUrlFmt, key, token), nullptr, {},
gmake[2]: *** [CMakeFiles/example1.dir/build.make:76: CMakeFiles/example1.dir/examples/example1.cpp.o] Error 1
gmake[1]: *** [CMakeFiles/Makefile2:89: CMakeFiles/example1.dir/all] Error 2

Bug fix - change to #define

# 1. Change this in kite.hpp
const string loginUrlFmt = "https://kite.zerodha.com/connect/login?v=3&api_key={api_key}";

# To this
#define loginUrlFmt "https://kite.zerodha.com/connect/login?v=3&api_key={api_key}"

# 2. Change this in ws.hpp
const string connectUrlFmt ="wss://ws.kite.trade/?api_key={0}&access_token={1}";

# To this
#define connectUrlFmt "wss://ws.kite.trade/?api_key={0}&access_token={1}"