Crow is C++ microframework for web. (inspired by Python Flask)

#include "crow.h"

int main()
{
    crow::SimpleApp app;

    CROW_ROUTE(app, "/")([](){
        return "Hello world";
    });

    app.port(18080).multithreaded().run();
}

Features

• Easy routing
  • Similiar to Flask
  • Type-safe Handlers (see Example)
• Very Fast
  • 
  • More data on crow-benchmark
• Fast built-in JSON parser (crow::json)
• Mustache based templating library (crow::mustache)
• Header only
• Provide an amalgamated header file `crow_all.h' with every features
• Middleware support

Still in development

• Built-in ORM

Examples

JSON Response

CROW_ROUTE(app, "/json")
([]{
    crow::json::wvalue x;
    x["message"] = "Hello, World!";
    return x;
});

Arguments

CROW_ROUTE(app,"/hello/<int>")
([](int count){
    if (count > 100)
        return crow::response(400);
    std::ostringstream os;
    os << count << " bottles of beer!";
    return crow::response(os.str());
});

Handler arguments type check at compile time

// Compile error with message "Handler type is mismatched with URL paramters"
CROW_ROUTE(app,"/another/<int>")
([](int a, int b){
    return crow::response(500);
});

Handling JSON Requests

CROW_ROUTE(app, "/add_json")
.methods("POST"_method)
([](const crow::request& req){
    auto x = crow::json::load(req.body);
    if (!x)
        return crow::response(400);
    int sum = x["a"].i()+x["b"].i();
    std::ostringstream os;
    os << sum;
    return crow::response{os.str()};
});

How to Build

If you just want to use crow, copy amalgamate/crow_all.h and include it.

Requirements

• C++ compiler with good C++11 support (tested with g++>=4.8)

• boost library

• CMake for build examples

• Linking with tcmalloc/jemalloc is recommended for speed.

• Now supporting VS2013 with limited functionality (only run-time check for url is available.)

Building (Tests, Examples)

Out-of-source build with CMake is recommended.

mkdir build
cd build
cmake ..
make

You can run tests with following commands:

ctest

Installing missing dependencies

Ubuntu

sudo apt-get install build-essential libtcmalloc-minimal4 && sudo ln -s /usr/lib/libtcmalloc_minimal.so.4 /usr/lib/libtcmalloc_minimal.so

OSX

brew install boost google-perftools

Attributions

Crow uses the following libraries.

qs_parse

https://github.com/bartgrantham/qs_parse

Copyright (c) 2010 Bart Grantham
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.