--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/eric7/Toolbox/SingleApplication.py Sat May 15 18:45:04 2021 +0200 @@ -0,0 +1,204 @@ +# -*- coding: utf-8 -*- + +# Copyright (c) 2004 - 2021 Detlev Offenbach <detlev@die-offenbachs.de> +# + +""" +Module implementing the single application server and client. +""" + +import json + +from PyQt5.QtCore import QByteArray +from PyQt5.QtNetwork import QLocalServer, QLocalSocket + +from E5Gui import E5MessageBox + +import Utilities + + +class SingleApplicationServer(QLocalServer): + """ + Class implementing the single application server base class. + """ + def __init__(self, name): + """ + Constructor + + @param name name this server is listening to (string) + """ + super().__init__() + + res = self.listen(name) + if not res: + # maybe it crashed last time + self.removeServer(name) + self.listen(name) + + self.newConnection.connect(self.__newConnection) + + self.qsock = None + + def __newConnection(self): + """ + Private slot to handle a new connection. + """ + sock = self.nextPendingConnection() + + # If we already have a connection, refuse this one. It will be closed + # automatically. + if self.qsock is not None: + return + + self.qsock = sock + + self.qsock.readyRead.connect(self.__receiveJson) + self.qsock.disconnected.connect(self.__disconnected) + + def __receiveJson(self): + """ + Private method to receive the data from the client. + """ + while self.qsock and self.qsock.canReadLine(): + line = bytes(self.qsock.readLine()).decode() + +## print(line) ## debug # __IGNORE_WARNING_M891__ + + try: + commandDict = json.loads(line.strip()) + except (TypeError, ValueError) as err: + E5MessageBox.critical( + None, + self.tr("Single Application Protocol Error"), + self.tr("""<p>The response received from the single""" + """ application client could not be decoded.""" + """ Please report this issue with the received""" + """ data to the eric bugs email address.</p>""" + """<p>Error: {0}</p>""" + """<p>Data:<br/>{1}</p>""").format( + str(err), Utilities.html_encode(line.strip())), + E5MessageBox.StandardButtons( + E5MessageBox.Ok)) + return + + command = commandDict["command"] + arguments = commandDict["arguments"] + + self.handleCommand(command, arguments) + + def __disconnected(self): + """ + Private method to handle the closure of the socket. + """ + self.qsock = None + + def shutdown(self): + """ + Public method used to shut down the server. + """ + if self.qsock is not None: + self.qsock.readyRead.disconnect(self.__parseLine) + self.qsock.disconnected.disconnect(self.__disconnected) + + self.qsock = None + + self.close() + + def handleCommand(self, command, arguments): + """ + Public slot to handle the command sent by the client. + + <b>Note</b>: This method must be overridden by subclasses. + + @param command command sent by the client + @type str + @param arguments list of command arguments + @type list of str + @exception RuntimeError raised to indicate that this method must be + implemented by a subclass + """ + raise RuntimeError("'handleCommand' must be overridden") + + +class SingleApplicationClient: + """ + Class implementing the single application client base class. + """ + def __init__(self, name): + """ + Constructor + + @param name name of the local server to connect to (string) + """ + self.name = name + self.connected = False + + def connect(self, timeout=10000): + """ + Public method to connect the single application client to its server. + + @param timeout connection timeout value in milliseconds + @type int + @return value indicating success or an error number. Value is one of: + <table> + <tr><td>0</td><td>No application is running</td></tr> + <tr><td>1</td><td>Application is already running</td></tr> + </table> + """ + self.sock = QLocalSocket() + self.sock.connectToServer(self.name) + if self.sock.waitForConnected(timeout): + self.connected = True + return 1 + else: + err = self.sock.error() + if err == QLocalSocket.LocalSocketError.ServerNotFoundError: + return 0 + else: + return -err + + def disconnect(self): + """ + Public method to disconnect from the Single Appliocation server. + """ + self.sock.disconnectFromServer() + self.connected = False + + def processArgs(self, args): + """ + Public method to process the command line args passed to the UI. + + <b>Note</b>: This method must be overridden by subclasses. + + @param args command line args (list of strings) + @exception RuntimeError raised to indicate that this method must be + implemented by a subclass + """ + raise RuntimeError("'processArgs' must be overridden") + + def sendCommand(self, command, arguments): + """ + Public method to send the command to the application server. + + @param command command to be sent to the server + @type str + @param arguments list of command arguments + @type list of str + """ + if self.connected: + commandDict = { + "command": command, + "arguments": arguments, + } + self.sock.write(QByteArray( + "{0}\n".format(json.dumps(commandDict)).encode() + )) + self.sock.flush() + + def errstr(self): + """ + Public method to return a meaningful error string for the last error. + + @return error string for the last error (string) + """ + return self.sock.errorString()