xml_settings_handler.py

import xml.sax, xml.sax.handler
from settings import Settings
import xml.etree.ElementTree as ET
import os.path

settingsPath = "data/settings.xml"

class SettingsHandler(xml.sax.handler.ContentHandler):

    def __init__(self):
        self.settings = Settings()
        self.buffer = ""
        self.attrBuffer = {}
        self.inMailSettings = False
        self.inSmtpServer = False

    def startElement(self, name, attributes):
        if name == "mail-settings": self.inMailSettings = True
        if name == "smtp-server": self.inSmtpServer = True

        for key in attributes.keys():
            self.attrBuffer.update({key: attributes[key]})

        return

    def characters(self, data):
        self.buffer += data

    def endElement(self, name):
        puffer = self.buffer.strip()

        if name == "calibre-folder":
            self.settings.setCalibreFolder(puffer)
        if name == "export-format":
            self.settings.setFormat(puffer)
        if self.inMailSettings:
            if name == "from":
                self.settings.setMailFrom(puffer)
            elif name == "to":
                self.settings.setMailTo(puffer)
                
            if self.inSmtpServer:
                if name == "address":
                    self.settings.setSmtpServer(puffer,
                        self.attrBuffer["port"],
                        self.attrBuffer["security"])
                elif name == "login":
                    self.settings.setSmtpLogin(puffer)
                elif name == "password":
                    self.settings.setSmtpPassword(puffer)

        # reset the stuff
        if name == "mail-settings": self.inMailSettings = False
        elif name == "smtp-server": self.inSmtpServer = False
        self.buffer = ""
        self.attrBuffer = {}

def loadSettings():
    if os.path.isfile(settingsPath):
        parser = xml.sax.make_parser()
        handler = SettingsHandler()
        parser.setContentHandler(handler)
        parser.parse(settingsPath)
        return handler.settings
    else:
        return Settings()

def saveSettings(settings):
    root = ET.Element("configuration")
    tree = ET.ElementTree(root)

    appendTextElement(root, "calibre-folder", settings.calibreFolder)
    appendTextElement(root, "export-format", settings.format)

    mailElem = ET.SubElement(root, "mail-settings")
    appendTextElement(mailElem, "from", settings.mailFrom)
    appendTextElement(mailElem, "to", settings.mailTo)

    if settings.smtpServer:
        smtpElem = ET.SubElement(mailElem, "smtp-server")
        addressElem = appendTextElement(smtpElem, "address", settings.mailFrom)

        if "port" in settings.smtpServer:
            addressElem.set("port", str(settings.smtpServer["port"]))
        if "security" in settings.smtpServer:
            addressElem.set("security", settings.smtpServer["security"])
        if "login" in settings.smtpServer:
            appendTextElement(smtpElem, "login", settings.smtpServer["login"])
        if "password" in settings.smtpServer:
            appendTextElement(smtpElem, "password", settings.smtpServer["password"])

    tree.write(settingsPath)

    return

def appendTextElement(parent, tagName, text):
    newElem = ET.SubElement(parent, tagName)
    newElem.text = text
    return newElem