Crow/docs/index.md

#
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<h4 align="center">A Fast and Easy to use microframework for the web.</h4>
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## 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](https://github.com/ipkn/crow-benchmark) and [this benchmark](https://github.com/guteksan/REST-CPP-benchmark)).
 - Built in JSON support.
 - [Mustache](http://mustache.github.io/) 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](https://github.com/crowcpp/crow/issues/8)

## Documentation
Available [here](https://crowcpp.github.io/crow).

## Examples

#### Hello World
```c++
#include "crow.h"

int main()
{
    crow::SimpleApp app;

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

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

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

#### Arguments
```cpp
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
```cpp
// 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
```cpp
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](https://github.com/crowcpp/crow/tree/master/examples).

## Setting Up / Building
Available [here](https://crowcpp.github.io/crow/getting_started/setup).