Issue 395 - Filter hits statistics backend

sitescripts/filterhits/web/submit.py

+# coding: utf-8
+
+# This file is part of the Adblock Plus web scripts,
+# Copyright (C) 2006-2014 Eyeo GmbH
+#
+# Adblock Plus is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License version 3 as
+# published by the Free Software Foundation.
+#
+# Adblock Plus 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 Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
+
+import MySQLdb, json, os
+from datetime import datetime
+from sitescripts.web import url_handler
+from sitescripts.utils import get_config, setupStderr
+
+import sitescripts.filterhits.common as common
+import sitescripts.filterhits.db as db
+import sitescripts.filterhits.geometrical_mean as geometrical_mean
+
+@url_handler("/submit")
+def submit(environ, start_response):
+  setupStderr(environ["wsgi.errors"])
+  config = get_config()
+
+  # Check that this is a POST request
+  if environ["REQUEST_METHOD"].upper() != "POST":

[Sebastian Noack, 2015/02/11 16:00:12]

According to the specs REQUEST_METHOD is always already uppercase:
http://wsgi.readthedocs.org/en/latest/definitions.html

[kzar, 2015/02/17 10:52:24]

Done.

+    return common.showError("Unsupported request method", start_response)
+
+  # Parse the submitted JSON
+  data = "{}"
+  try:
+    data_length = int(environ.get("CONTENT_LENGTH", "0"))
+  except ValueError:

[Sebastian Noack, 2015/02/11 16:00:12]

If you just catch the KeyError as well you can use canonical key lookups, and
don't need to specify the fallback twice: 

try:
  data_length = int(environ["CONTENT_LENGTH"])
except (ValueError, KeyError):
  data_length = 0

[kzar, 2015/02/17 10:52:24]

Done.

+    data_length = 0
+  if data_length != 0:
+    data = environ["wsgi.input"].read(data_length)
+  try:
+    data = json.loads(data)
+  except json.decoder.JSONDecodeError:
+    return common.showError("Error while parsing JSON data.", start_response)
+
+  # Make sure it looks roughly valid
+  if not common.valid_log_data(data):
+    return common.showError("Data looks invalid.", start_response)
+
+  # Log the data to a file
+  log_dir = config.get("filterhitstats", "log_dir")
+  try:
+    log_file = common.log_filterhits(data, log_dir,
+                                     environ.get("QUERY_STRING", ""))
+  except OSError, IOError:

[Sebastian Noack, 2015/02/11 16:00:12]

You need parentheses here. Otherwise - as it currently is - the catched OSError
will be stored in the variable IOError, while IOErrors are not handled.

[kzar, 2015/02/17 10:52:24]

Done.

+    return common.showError("Failed to write data to log file!", start_response,
+                            "500 Logging error")
+
+  # Update the geometrical_mean aggregations in the database
+  interval = config.get("filterhitstats", "interval")
+  try:
+    db.connect(config.get("filterhitstats", "dbuser"),
+               config.get("filterhitstats", "dbpassword"),
+               config.get("filterhitstats", "database"))
+    db.write(geometrical_mean.update(interval, data))
+  except MySQLdb.Error, e:
+    # Updating the aggregations in the database failed for whatever reason,
+    # log the details but continue to return 200 OK to the client to avoid
+    # re-transmission of the data.
+    mysql_error_log = os.path.join(config.get("filterhitstats", "log_dir"),
+                                   "mysql-errors.log")
+    with open(mysql_error_log, "a+") as f:
+      f.write("[%s] MySQL error (%d) when processing data file %s: \"%s\"\n" % (
+        datetime.now().strftime('%d/%b/%Y:%H:%M:%S %z'),
+        e.args[0], log_file, e.args[1]
+      ))
+  finally:
+    db.disconnect()
+
+  # Send back a 200 OK response
+  response_headers = [("Content-type", "text/plain")]
+  start_response("200 OK", response_headers)
+  return []