descpage: Implement loading, parsing and updating

To be able to change file description page, we need to load current
text, do manipulations and to update with new text

Issue #1 (#1)

euroexchange/descpage.py

@@ -0,0 +1,73 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+#
+#  descpage.py
+#
+#  Copyright 2018 Jonathan Golder <jonathan@golderweb.de>
+#
+#  This program is free software; you can redistribute it and/or modify
+#  it under the terms of the GNU General Public License as published by
+#  the Free Software Foundation; either version 2 of the License, or
+#  (at your option) any later version.
+#
+#  This program is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#  GNU General Public License for more details.
+#
+#  You should have received a copy of the GNU General Public License
+#  along with this program; if not, write to the Free Software
+#  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+#  MA 02110-1301, USA.
+#
+#
+
+import os
+
+import pywikibot
+import mwparserfromhell as mwparser
+
+from config import Config
+
+class DescPageBot(pywikibot.bot.Bot):
+    """
+    Updates file description page with EuroExchangeBot related content
+    """
+
+    def treat_job( self, job ):
+        """
+        Handles work on file description page for given job
+
+        @param job Job to work on
+        @type EuroExchangeBotJob
+        """
+        # Store job
+        self.job = job
+        # Store file page object
+        self.current_page = job.filepage
+
+        # Parse filepage
+        self.parse_page()
+
+        # Update wiki page
+        self.update_page()
+
+    def parse_page(self):
+        """
+        Load current page content and parse with mwparser
+        """
+        self.current_page.wikicode = mwparser.parse(self.current_page.text)
+
+    def update_page(self):
+        """
+        Put updated content to wiki
+        """
+
+        # Convert wikicode back to str
+        new_text = str(self.current_page.wikicode)
+
+        # Save new text
+        self.userPut( self.current_page,
+                      self.current_page.text,
+                      new_text,
+                      summary=Config.gnuplot_script_comment )