diff -r 4e8b98454baa -r 800c432b34c8 eric7/Toolbox/SingleApplication.py
--- /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()
