Server Class Reference

Description

Object representing a Cadabra server, capable of receiving messages on a websocket, running Python code, and sending output back to the client.

Contains the logic to intercept raw Python output but also provides functionality to the Python side which enables clients to send various objects in JSON encoded form. See Server::on_block_finished for the format of these messages.

Every block is run on the same Python scope. They run sequentially, one at a time, on a thread separate from the websocket++ main loop. When the Python code finishes (or when it is interrupted), this thread locks the socket_mutex and calls on_block_finished().

#include <Server.hh>

Inheritance diagram for Server:

Classes
class	Block
class	CatchOutput
	Python output catching. More...
class	Connection

Public Member Functions
	Server ()
	Server (const Server &)=delete
	Server (const std::string &socket)
	~Server ()
void	run ()
	The only user-visible part: just instantiate a server object and start it with run(). More...
Public Member Functions inherited from ProgressMonitor
	ProgressMonitor ()
virtual	~ProgressMonitor ()
virtual void	group (std::string name="")
virtual void	progress (int n, int total)
void	print () const
std::vector< Total >	totals () const

Public Attributes
CatchOutput	catchOut
CatchOutput	catchErr
Stopwatch	server_stopwatch
Stopwatch	sympy_stopwatch

Private Types
typedef websocketpp::server < websocketpp::config::asio >	WebsocketServer
typedef std::map < websocketpp::connection_hdl, Connection, std::owner_less < websocketpp::connection_hdl > >	ConnectionMap

Private Member Functions
void	init ()
void	on_socket_init (websocketpp::connection_hdl hdl, boost::asio::ip::tcp::socket &s)
void	on_message (websocketpp::connection_hdl hdl, WebsocketServer::message_ptr msg)
void	on_open (websocketpp::connection_hdl hdl)
void	on_close (websocketpp::connection_hdl hdl)
void	wait_for_job ()
std::string	run_string (const std::string &, bool handle_output=true)
void	on_block_finished (Block)
	Called by the run_block() thread upon completion of the task. More...
void	on_block_error (Block)
void	on_kernel_fault (Block)
std::string	architecture () const
bool	handles (const std::string &otype) const
uint64_t	send (const std::string &output, const std::string &msg_type, uint64_t parent_id=0, bool last_in_sequence=false)
	Raw code to send a string (which must be JSON formatted) as a message to the client. More...
void	send_json (const std::string &)
void	stop_block ()
	Halt the currently running block and prevent execution of any further blocks that may still be on the queue. More...
void	dispatch_message (websocketpp::connection_hdl, const std::string &json_string)
	Takes a JSON encoded message and performs the required action to process it. More...

Private Attributes
WebsocketServer	wserver
std::string	socket_name
ConnectionMap	connections
std::mutex	ws_mutex
std::thread	runner
std::mutex	block_available_mutex
std::condition_variable	block_available
std::queue< Block >	block_queue
websocketpp::connection_hdl	current_hdl
uint64_t	current_id
uint64_t	return_cell_id
bool	started
std::future< std::string >	job
boost::python::object	main_module
boost::python::object	main_namespace
int	cells_ran

Member Typedef Documentation

typedef std::map<websocketpp::connection_hdl, Connection, std::owner_less<websocketpp::connection_hdl> > Server::ConnectionMap

private

typedef websocketpp::server<websocketpp::config::asio> Server::WebsocketServer

private

Constructor & Destructor Documentation

Server::Server

(

)

Server::Server ( const Server &  )

delete

Server::Server

(

const std::string &

socket

)

Server::~Server

(

)

Member Function Documentation

std::string Server::architecture ( ) const

private

void Server::dispatch_message ( websocketpp::connection_hdl  hdl, const std::string &  json_string  )

private

Takes a JSON encoded message and performs the required action to process it.

Where applicable these messages are compatible with IPython's message types, http://ipython.org/ipython-doc/dev/development/messaging.html

bool Server::handles ( const std::string &  otype ) const

private

void Server::init ( )

private

void Server::on_block_error ( Block  blk )

private

void Server::on_block_finished ( Block  blk )

private

Called by the run_block() thread upon completion of the task.

This will send any output generated by printing directly to stdout or stderr from Python (so, output not generated by using the 'display' function). Indicates to the client that this block has finished executing. Will send an empty string if there has been no output 'print'ed.

void Server::on_close ( websocketpp::connection_hdl  hdl )

private

void Server::on_kernel_fault ( Block  blk )

private

void Server::on_message ( websocketpp::connection_hdl  hdl, WebsocketServer::message_ptr  msg  )

private

void Server::on_open ( websocketpp::connection_hdl  hdl )

private

void Server::on_socket_init ( websocketpp::connection_hdl  hdl, boost::asio::ip::tcp::socket &  s  )

private

void Server::run

(

)

The only user-visible part: just instantiate a server object and start it with run().

This will not return until the server has been shut down.

std::string Server::run_string ( const std::string &  blk, bool  handle_output = true  )

private

uint64_t Server::send ( const std::string &  output, const std::string &  msg_type, uint64_t  parent_id = 0, bool  last_in_sequence = false  )

private

Raw code to send a string (which must be JSON formatted) as a message to the client.

Handles communication of the result back to the client in JSON format. This is always of the form

 { "header":   { "parent_id":     "...",
                 "parent_origin": "client" | "server", 
                 "cell_id":       "...", 
                 "cell_origin":   "client" | "server"  

}, "content": { "output": "..." }, "msg_type": "..." } msg_type can be "output", "latex", "image_png" and so on, corresponding to the possible values of DataCell::CellType.

Returns the serial number of the new cell sent.

void Server::send_json ( const std::string &  msg )

private

void Server::stop_block ( )

private

Halt the currently running block and prevent execution of any further blocks that may still be on the queue.

void Server::wait_for_job ( )

private

Member Data Documentation

std::condition_variable Server::block_available

private

std::mutex Server::block_available_mutex

private

std::queue<Block> Server::block_queue

private

CatchOutput Server::catchErr

CatchOutput Server::catchOut

int Server::cells_ran

private

ConnectionMap Server::connections

private

websocketpp::connection_hdl Server::current_hdl

private

uint64_t Server::current_id

private

std::future<std::string> Server::job

private

boost::python::object Server::main_module

private

boost::python::object Server::main_namespace

private

uint64_t Server::return_cell_id

private

std::thread Server::runner

private

Stopwatch Server::server_stopwatch

std::string Server::socket_name

private

bool Server::started

private

Stopwatch Server::sympy_stopwatch

std::mutex Server::ws_mutex

private

WebsocketServer Server::wserver

private

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

• client_server/Server.hh
• client_server/Server.cc