FastCGI integration for HttpServer. More...

#include <fastcgibackend.hpp>

Inheritance diagram for Nuria::FastCgiBackend:

Signals
void	connectionAdded ()

void	connectionClosed ()

Public Member Functions
	FastCgiBackend (HttpServer *server)

	~FastCgiBackend () override

int	currentConnectionCount () const

QMap< QByteArray, QByteArray >	customConfiguration () const

bool	isListening () const

bool	isSecure () const

bool	listen ()

bool	listen (int port, const QHostAddress &iface=QHostAddress::Any)

bool	listenLocal (const QString &name, QLocalServer::SocketOptions options=QLocalServer::NoOptions)

bool	listenLocal (qintptr handle)

int	maxConcurrentConnections () const

int	maxConcurrentRequests () const

int	port () const

void	setCustomConfiguration (const QByteArray &name, const QByteArray &value)

void	setMaxConcurrentConnections (int count)

void	setMaxConcurrentRequests (int count) const

void	stop ()

Public Member Functions inherited from Nuria::HttpBackend
	HttpBackend (HttpServer *server)

	~HttpBackend ()

HttpServer *	httpServer () const

Protected Member Functions
void	serverThreadCreated (QThread *thread) override

Friends
class	Internal::FastCgiThreadObject

Detailed Description

FastCGI integration for HttpServer.

This class provides a FastCGI backend for HttpServer. Using this you can write FastCGI servers easily.

Note: This implementation only supports writing FCGI responders.

Usage

This implementation supports both, opening a TCP socket which the front-end HTTP server pushes requests to or inheriting the socket opened by the front-end server from the FCGI_LISTENSOCK_FILENO environment variable.

FastCGI parameter

FastCGI front-end servers pass "parameters" to FastCGI applications to tell them about incoming connections. These are comparable to environment variables or HTTP headers.

The following parameters are needed by FastCgiBackend:

REQUEST_METHOD (HTTP verb)
REQUEST_URI (Path)
REMOTE_ADDR (Peer address)
REMOTE_PORT (Peer port)
SERVER_ADDR (Server address)
SERVER_PORT (Server port)
SERVER_PROTOCOL ("HTTP/1.x")

Parameters whose name begin with "HTTP_" are stripped of that prefix. All FastCGI parameters are forwarded to the HttpClient and can be accessed by HttpClient::requestHeader(), with names are converted from "THIS_FORMAT" to "This-Format". Example:

client->requestHeader ("Some-Thing"); // Access the SOME_THING FCGI parameter

client->requestHeader ("Host"); // Access the HTTP_HOST FCGI parameter

A note on logging

You should think about where to put your logs. Some front-end servers support receiving log messages through the standard output or error streams. Whatever you choose, if you need to change the default logging target, see Debug::setDestination().

Behaviour in high-load scenarios

It should be pointed out that all tested front-end HTTP servers, namely lighttpd and nginx, work equally well with this implementation in normal circumstances. Though it should be noted that benchmarking showed that nginx is inferior to lighttpd one. With about 1k concurrent requests done by the benchmarking utility, nginx suffered from having issues serving the last ca. 10% of all requests. Lighttpd does not have this restriction.

These restriction do not apply when configuring both servers to act as a HTTP proxy and relying on the NuriaFrameworks HTTP implementation.

Constructor & Destructor Documentation

Nuria::FastCgiBackend::FastCgiBackend ( HttpServer * server )

explicit

Constructor.

Nuria::FastCgiBackend::~FastCgiBackend ( )

override

Destructor.

Member Function Documentation

void Nuria::FastCgiBackend::connectionAdded ( )

signal

The FastCGI front-end server has opened a new connection to the back-end.

void Nuria::FastCgiBackend::connectionClosed ( )

signal

The FastCGI front-end server has closed a connection.

Note: Don't connect to this signal using Qt::DirectConnection.

int Nuria::FastCgiBackend::currentConnectionCount ( ) const

Returns the count of connections currently opened by the FastCGI front-end server.

QMap< QByteArray, QByteArray > Nuria::FastCgiBackend::customConfiguration ( ) const

Returns teh custom configuration map.

bool Nuria::FastCgiBackend::isListening ( ) const

virtual

Returns true if the server is currently listening for connections.

Implements Nuria::HttpBackend.

bool Nuria::FastCgiBackend::isSecure ( ) const

virtual

Returns true if this back-end uses secure connections. The default implementation returns false.

Reimplemented from Nuria::HttpBackend.

bool Nuria::FastCgiBackend::listen ( )

Start listening on the socket forwarded to this process. This is mainly there for front-end servers

bool Nuria::FastCgiBackend::listen	(	int	port,
		const QHostAddress &	iface = `QHostAddress::Any`
	)

Listen for TCP connections on port and iface.

bool Nuria::FastCgiBackend::listenLocal	(	const QString &	name,
		QLocalServer::SocketOptions	options = `QLocalServer::NoOptions`
	)

Listens on name using a QLocalServer.

bool Nuria::FastCgiBackend::listenLocal ( qintptr handle )

Listens on handle using a QLocalServer.

int Nuria::FastCgiBackend::maxConcurrentConnections ( ) const

Returns the max amount of concurrent connections. Defaults to the count of CPU cores of the host machine.

int Nuria::FastCgiBackend::maxConcurrentRequests ( ) const

Returns the max amount of concurrent requests. Defaults to: (count of CPU cores) * 10

int Nuria::FastCgiBackend::port ( ) const

virtual

Returns the port this server is listening on, or -1 if it's not listening.

Implements Nuria::HttpBackend.

void Nuria::FastCgiBackend::serverThreadCreated ( QThread * thread )

overrideprotectedvirtual

Called by the HttpServer when a new server thread has been created. This lets back-ends register their own thread-specific bookkeeping routines.

This function will also be called by the HttpServer if no multi-threading is used. In this case, the function will be called once with thread being the one the server is associated with.

To run some kind of initialization after the thread has been started, use one of:

QTimer::singleShot (0, object, SLOT(...)); // Pre Qt5.4
QTimer::singleShot (0, object, &Object::...); // Qt5.4 and up
QTimer::singleShot (0, []() { ... }); // Qt5.4 and up

Note: The function is called in the thread the HttpServer lives in.

The default implementation does nothing.

Reimplemented from Nuria::HttpBackend.

void Nuria::FastCgiBackend::setCustomConfiguration	(	const QByteArray &	name,
		const QByteArray &	value
	)

Sets a custom configuration field for FastCGI front-end servers. This field will be sent to the FCGI server after receiving a FCGI_GET_VALUES request.

If there's already a configuration for name, it will be overriden.

void Nuria::FastCgiBackend::setMaxConcurrentConnections ( int count )

Sets the max amount of concurrent connections.

void Nuria::FastCgiBackend::setMaxConcurrentRequests ( int count ) const

Sets the max amount of concurrent requests.

void Nuria::FastCgiBackend::stop ( )

Stops listening immediately.

The documentation for this class was generated from the following file:

fastcgibackend.hpp

Signals

Public Member Functions

Protected Member Functions

Friends

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation