From 0fcbfe0bd97867a9b5bce29e72570529d4788b15 Mon Sep 17 00:00:00 2001
From: Peter Molnar <hello@petermolnar.eu>
Date: Wed, 14 Aug 2019 10:17:20 +0100
Subject: [PATCH] this is a replacement for the removed memento functionality;
 a tiny wayback machine crawler that tried to look up the earliest saved
 version of a page

---
 wayback.py | 87 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 87 insertions(+)
 create mode 100644 wayback.py

diff --git a/wayback.py b/wayback.py
new file mode 100644
index 0000000..35a6495
--- /dev/null
+++ b/wayback.py
@@ -0,0 +1,87 @@
+__author__ = "Peter Molnar"
+__copyright__ = "Copyright 2017-2019, Peter Molnar"
+__license__ = "apache-2.0"
+__maintainer__ = "Peter Molnar"
+__email__ = "mail@petermolnar.net"
+
+import re
+import json
+import os
+import logging
+import requests
+from collections import deque
+from urllib.parse import urlparse
+import settings
+import arrow
+
+logger = logging.getLogger("wayback")
+logger.setLevel(10)
+
+console_handler = logging.StreamHandler()
+formatter = logging.Formatter("%(asctime)s - %(name)s - %(levelname)s - %(message)s")
+console_handler.setFormatter(formatter)
+logger.addHandler(console_handler)
+
+from pprint import pprint
+
+RE_FIRST = re.compile(r"^\<(?P<url>[^>]+)\>; rel=\"first memento\"; datetime=\"(?P<datetime>[^\"]+).*$")
+
+class FindWaybackURL(object):
+
+    def __init__(self, path, category="", redirects=[]):
+        self.path = path
+        self.category = category
+        self.redirects = redirects
+        self.epoch = int(arrow.utcnow().timestamp)
+        self.oldest = ""
+
+    def possible_urls(self):
+        q = {}
+        paths = self.redirects
+        paths.append(self.path)
+        for path in paths:
+            q[f"http://{settings.site.name}/{path}/"] = True
+            q[f"http://{settings.site.name}/{path}/index.html"] = True
+
+            domains = settings.formerdomains
+            domains.append(settings.site.name)
+
+            for domain in domains:
+                q[f"http://{domain}/{path}/"] = True
+                if self.category in settings.formercategories:
+                    categories = settings.formercategories[self.category]
+                else:
+                    categories = []
+                categories.append(self.category)
+                for category in categories:
+                    q[f"http://{domain}/{category}/{path}/"] = True
+                    q[f"http://{domain}/category/{category}/{path}/"] = True
+        #logger.info("possible urls: %s", json.dumps(list(q.keys()), indent=4, ensure_ascii=False))
+        return list(q.keys())
+
+    def get_first_memento(self, url):
+        target = f"http://web.archive.org/web/timemap/link/{url}"
+        mementos = requests.get(target)
+        if not mementos.text:
+            return None
+        for memento in mementos.text.split("\n"):
+            m = RE_FIRST.match(memento)
+            if m:
+                return settings.nameddict({
+                    'epoch': int(arrow.get(m.group('datetime'), "ddd, DD MMM YYYY HH:mm:ss ZZZ").to("utc").timestamp),
+                    'url': m.group('url')
+                })
+
+    def run(self):
+        l = self.possible_urls()
+        logging.info("running archive.org lookup for %s", self.path)
+        for url in l:
+            maybe = self.get_first_memento(url)
+            if maybe:
+                if maybe.epoch < self.epoch:
+                    self.epoch = maybe.epoch
+                    self.oldest = maybe.url
+        if not len(self.oldest):
+            logger.error("no memento found for %s", self.path)
+        else:
+            logger.info("\t\toldest found memento for %s: %s :: %s", self.path, str(arrow.get(self.epoch)), self.oldest)