# Crow

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#

#### A Fast and Easy to use microframework for the web.

## Description

Crow is a C++ microframework for running web services. It uses routing similar to Python's Flask which makes it easy to use. It is also extremely fast, beating multiple existing C++ frameworks as well as non C++ frameworks.

### Features

- Easy Routing (similar to flask).
- Type-safe Handlers.
- Blazingly fast (see this benchmark and this benchmark).
- Built in JSON support.
- Mustache based templating library (`crow::mustache`).
- Header only library (single header file available).
- Middleware support for extensions.
- HTTP/1.1 and Websocket support.
- Multi-part request and response support.
- Uses modern C++ (11/14)

### Still in development

- HTTP/2 support

## Documentation

Available here.

## Examples

#### Hello World

    #include "crow.h"

    int main()
    {
        crow::SimpleApp app;

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

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

#### 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()};
    });

More examples can be found here.

## Setting Up / Building

Available here.