From 91fc1146505d33629cc80199aa1a5881565e4e50 Mon Sep 17 00:00:00 2001
From: Nguyễn Gia Phong <mcsinyx@disroot.org>
Date: Tue, 8 Nov 2022 18:58:14 +0900
Subject: Parse all necessary information

---
 src/fead.py | 52 +++++++++++++++++++++++++++++++---------------------
 1 file changed, 31 insertions(+), 21 deletions(-)

diff --git a/src/fead.py b/src/fead.py
index d9b94a3..eede317 100755
--- a/src/fead.py
+++ b/src/fead.py
@@ -21,14 +21,17 @@ from datetime import datetime
 from email.utils import parsedate_to_datetime
 from http.client import HTTPResponse
 from io import BytesIO
+from operator import attrgetter
 from sys import stdin
 from urllib.error import HTTPError
 from urllib.parse import urljoin, urlsplit
+from warnings import warn
 from xml.etree.ElementTree import fromstring as parse_xml
 
 REQUEST = 'GET {} HTTP/1.0\r\nHost: {}\r\n\r\n'
-Feed = namedtuple('Feed', ('title', 'items'))
-Item = namedtuple('Item', ('title', 'link', 'date', 'description'))
+Item = namedtuple('Item', ('title', 'link', 'time', 'summary'))
+Advert = namedtuple('Advert', ('source_title', 'source_link',
+                               'title', 'link', 'time', 'summary'))
 
 
 class BytesSocket:
@@ -44,7 +47,7 @@ class BytesSocket:
 
 def parse_rss_item(xml):
     """Parse given RSS item."""
-    date = None
+    time = datetime.fromtimestamp(0).astimezone(None)
     description = ''
     for child in xml:
         if child.tag == 'title':
@@ -52,56 +55,61 @@ def parse_rss_item(xml):
         elif child.tag == 'link':
             link = child.text
         elif child.tag == 'pubDate':
-            date = parsedate_to_datetime(child.text)
+            time = parsedate_to_datetime(child.text).astimezone(None)
         elif child.tag == 'description':
             description = child.text
         elif child.tag == 'content:encoded' and not description:
             description = child.text
     if not description:
         description = xml.text
-    return Item(title, link, date, description)
+    return Item(title, link, time, description)
 
 
-def parse_rss(xml, url):
+def parse_rss(xml, title):
     """Parse given RSS feed."""
-    title = url
     items = []
     for child in xml:
         if child.tag == 'title':
             title = child.text
+        elif child.tag == 'link':
+            link = child.text
         elif child.tag == 'item':
             items.append(parse_rss_item(child))
-    return Feed(title, items)
+    return Advert(title, link, *max(items, key=attrgetter('time')))
 
 
 def parse_atom_entry(xml):
     """Parse given Atom entry."""
-    date = None
+    time = datetime.fromtimestamp(0).astimezone(None)
     summary = ''
     for child in xml:
         if child.tag.endswith('Atom}title'):
             title = child.text
         elif child.tag.endswith('Atom}link'):
-            link = child.attrib['href']
+            rel = child.attrib.get('rel')
+            if rel == 'alternate' or not rel: link = child.attrib['href']
         elif child.tag.endswith('Atom}published'):
-            date = datetime.fromisoformat(child.text.replace('Z', '+00:00'))
+            iso = child.text.replace('Z', '+00:00') # normalized
+            time = datetime.fromisoformat(iso).astimezone(None)
         elif child.tag.endswith('Atom}summary'):
             summary = child.text
         elif child.tag.endswith('Atom}content') and not summary:
             summary = child.text
-    return Item(title, link, date, summary)
+    return Item(title, link, time, summary)
 
 
-def parse_atom(xml, url):
+def parse_atom(xml, title):
     """Parse given Atom feed."""
-    title = url
     entries = []
     for child in xml:
         if child.tag.endswith('Atom}title'):
             title = child.text
+        elif child.tag.endswith('Atom}link'):
+            rel = child.attrib.get('rel')
+            if rel == 'alternate' or not rel: link = child.attrib['href']
         elif child.tag.endswith('Atom}entry'):
             entries.append(parse_atom_entry(child))
-    return Feed(title, entries)
+    return Advert(title, link, *max(entries, key=attrgetter('time')))
 
 
 async def fetch(url):
@@ -119,11 +127,12 @@ async def fetch(url):
     response.begin()
     with response:
         if response.status >= 400:
-            raise HTTPError(url.geturl(), response.status, response.reason,
+            raise HTTPError(url.geturl(), response.status,
+                            f'{response.reason}: {url.geturl()}',
                             response.getheaders(), response)
         if response.status >= 300:
             location = urljoin(url.geturl(), response.getheader('Location'))
-            print(url.geturl(), '->', location)
+            warn(f'{url.geturl()} redirects to {location}')
             return await fetch(urlsplit(location))
         if response.status >= 200:
             xml = parse_xml(response.read())
@@ -133,7 +142,9 @@ async def fetch(url):
             if xml.tag.endswith('Atom}feed'):
                 return parse_atom(xml, url.hostname)
             raise ValueError(f'unsupported feed format at {url.geturl()}')
-        # FIXME: handle informational responses
+        raise HTTPError(url.geturl(), response.status,
+                        f'{response.reason}: {url.geturl()}',
+                        response.getheaders(), response)
 
 
 async def fetch_all(urls):
@@ -147,6 +158,5 @@ async def fetch_all(urls):
 
 
 if __name__ == '__main__':
-    feeds = run(fetch_all(stdin.readlines()))
-    for feed in feeds:
-        print(feed)
+    feeds = sorted(run(fetch_all(stdin.readlines())),
+                   key=attrgetter('time'), reverse=True)
-- 
cgit 1.4.1