Spot the difference on the web

Davide Alberani 9358360c7c Merge pull request #15 from qqgg231/patch-1 5 months ago
conf 4261623d1a add documentation 1 year ago
dist e7d1ed6faa fix for empty strings 1 year ago
docs 4261623d1a add documentation 1 year ago
ssl d249420df3 ssl directory 1 year ago
storage 85cbdc00ad commit to git repository 1 year ago
.gitignore 85cbdc00ad commit to git repository 1 year ago
Dockerfile cadc6ec2d8 Docker file 1 year ago
LICENSE.txt 3e5be6d58c skeleton of scheduler 1 year ago 95aecc9c85 added lxml and pytz dependencies 5 months ago 9f8c1c9387 fix #14: avoid crashing if storage directory is missing 8 months ago 2678000d68 update file permission 1 year ago


Spot the difference on the web.

Tired of clicking F5 waiting for a change on a web page? Define a list of pages to watch, and receive an email when something has changed.

Install, run, develop and debug


Just run:


Old-fashioned installation

To install it:

sudo python3
# if you want to install these modules for an unprivileged user, add --user and remove "sudo";
# if you want to upgrade the versions already present in the system, also add --upgrade
sudo pip3 install lxml
sudo pip3 install pytz
sudo pip3 install apscheduler
sudo pip3 install requests
sudo pip3 install sqlalchemy
sudo pip3 install tornado
git clone
cd diffido
./ --debug

Now you can point your browser to http://localhost:3210/

You can also run the server in https, putting in the ssl directory two files named diffido_key.pem and diffido_cert.pem


You can edit the conf/diffido.conf file (Python syntax) to change the global settings; you almost surely have to configure the SMTP settings, at least.

Each schedule has its own web page GUI; the settings should be pretty self-explanatory, except:

  • XPath selector: define which portion of a web page to consider
  • minimum change: float between 0.0 and 1.0, which represent the minimum amount of the page (in percentage of number of lines) that has to be changed to send a notification; if left empty, any change will be notified
  • crontab: a complete crontab definition, to specify the period of the check


See the docs/ file for more information about how to contribute.

Technological stack

License and copyright

Copyright 2018 Davide Alberani

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.