From 845c47403eff26e09485e81c3b407d36ab9d8644 Mon Sep 17 00:00:00 2001
From: Noah Petherbridge <root@kirsle.net>
Date: Tue, 16 Dec 2014 03:49:03 +0000
Subject: [PATCH] Cache locking, markdown wrapping, referer fixing

---
 rophako/jsondb.py         | 42 ++++++++++++++++-----------------------
 rophako/model/tracking.py | 15 +++++++++++---
 rophako/utils.py          |  4 +++-
 3 files changed, 32 insertions(+), 29 deletions(-)

diff --git a/rophako/jsondb.py b/rophako/jsondb.py
index 2d52851..89cfd46 100644
--- a/rophako/jsondb.py
+++ b/rophako/jsondb.py
@@ -42,13 +42,20 @@ def get(document, cache=True):
         else:
             return data
 
+    # Get a lock for reading.
+    lock = lock_cache(document)
+
     # Get the JSON data.
     data = read_json(path)
 
+    # Unlock!
+    unlock_cache(lock)
+
     # Cache and return it.
     if cache:
         set_cache(document, data, expires=cache_lifetime)
         set_cache(document+"_mtime", stat.st_mtime, expires=cache_lifetime)
+
     return data
 
 
@@ -56,8 +63,7 @@ def commit(document, data, cache=True):
     """Insert/update a document in the DB."""
 
     # Only allow one commit at a time.
-    if not lock_cache(document):
-        return
+    lock = lock_cache(document)
 
     # Need to create the file?
     path = mkpath(document)
@@ -83,7 +89,7 @@ def commit(document, data, cache=True):
         set_cache(document+"_mtime", time.time(), expires=cache_lifetime)
 
     # Release the lock.
-    unlock_cache(document)
+    unlock_cache(lock)
 
 
 def delete(document):
@@ -166,15 +172,10 @@ def write_json(path, data):
     logger.debug("JsonDB: WRITE > {}".format(path))
 
     # Open and lock the file.
-    fh = None
-    if os.path.isfile(path):
-        fh = codecs.open(path, 'r+', 'utf-8')
-    else:
-        fh = codecs.open(path, 'w', 'utf-8')
+    fh = codecs.open(path, 'w', 'utf-8')
     flock(fh, LOCK_EX)
 
     # Write it.
-    fh.truncate(0)
     fh.write(json.dumps(data, sort_keys=True, indent=4, separators=(',', ': ')))
 
     # Unlock and close.
@@ -243,25 +244,16 @@ def lock_cache(key, timeout=5, expire=20):
 
     Returns True on success, None on failure to acquire lock."""
     lock_key = key + "_lock"
-    begin    = int(time.time())
-
-    lock = get_cache(lock_key)
-    while lock:
-        time.sleep(0.2)
-        lock = get_cache(lock_key)
-        if int(time.time()) - begin >= timeout:
-            handle_exception(
-                Exception("Redis key lock timed out waiting for {}".format(key))
-            )
-            return None
+    client   = get_redis()
 
     # Take the lock.
-    set_cache(lock_key, time.time(), expire)
+    lock = client.lock(key, timeout=expire)
+    lock.acquire()
     logger.debug("Cache lock acquired: {}, expires in {}s".format(key, expire))
-    return True
+    return lock
 
 
-def unlock_cache(key):
+def unlock_cache(lock):
     """Release the lock on a cache key."""
-    del_cache(key + "_lock")
-    logger.debug("Cache lock released: {}".format(key))
+    lock.release()
+    logger.debug("Cache lock released")
diff --git a/rophako/model/tracking.py b/rophako/model/tracking.py
index 4b367eb..529fac2 100644
--- a/rophako/model/tracking.py
+++ b/rophako/model/tracking.py
@@ -97,6 +97,15 @@ def log_referrer(request, link):
             timeout=5,
             verify=False, # Don't do SSL verification
         )
+
+        # Make sure the request didn't just redirect back to our main site
+        # (e.g. http://whatever.example.com wildcard may redirect back to
+        # http://example.com, and if that's us, don't log that!
+        if r.url.startswith("http://{}".format(hostname)) or \
+           r.url.startswith("https://{}".format(hostname)):
+            return None
+
+        # Look for our hostname in their page.
         if hostname in r.text:
             # Log it.
             db = list()
@@ -106,9 +115,8 @@ def log_referrer(request, link):
             db.append(link)
             JsonDB.commit("traffic/referrers", db, cache=False)
             return link
-    except Exception as e:
-        handle_exception(e)
-        return None
+    except:
+        pass
 
     return None
 
@@ -206,5 +214,6 @@ def get_referrers(recent=25):
 
     recent = 0 - recent
     result["recent"] = db[recent:]
+    result["recent"].reverse()
 
     return result
diff --git a/rophako/utils.py b/rophako/utils.py
index 4ca85b3..6141fc1 100644
--- a/rophako/utils.py
+++ b/rophako/utils.py
@@ -163,7 +163,9 @@ def render_markdown(body, html_escape=True, extensions=None, blacklist=None):
         for ext in blacklist:
             args["extensions"].remove(str(ext))
 
-    return markdown.markdown(body, **args)
+    return '<div class="markdown">{}</div>'.format(
+        markdown.markdown(body, **args)
+    )
 
 
 def send_email(to, subject, message, sender=None, reply_to=None):