Healthchecks
Healthchecks is a cron job monitoring service. It listens for HTTP requests and email messages ("pings") from your cron jobs and scheduled tasks ("checks"). When a ping does not arrive on time, Healthchecks sends out alerts.
Healthchecks comes with a web dashboard, API, 25+ integrations for delivering notifications, monthly email reports, WebAuthn 2FA support, team management features: projects, team members, read-only access.
The building blocks are:
- Python 3.6+
- Django 3
- PostgreSQL or MySQL
Healthchecks is licensed under the BSD 3-clause license.
Healthchecks is available as a hosted service at https://healthchecks.io/.
Setting Up for Development
To set up Healthchecks development environment:
-
Install dependencies (Debian/Ubuntu):
$ sudo apt-get update $ sudo apt-get install -y gcc python3-dev python3-venv libpq-dev
-
Prepare directory for project code and virtualenv. Feel free to use a different location:
$ mkdir -p ~/webapps $ cd ~/webapps
-
Prepare virtual environment (with virtualenv you get pip, we'll use it soon to install requirements):
$ python3 -m venv hc-venv $ source hc-venv/bin/activate $ pip3 install wheel # make sure wheel is installed in the venv
-
Check out project code:
$ git clone https://github.com/healthchecks/healthchecks.git
-
Install requirements (Django, ...) into virtualenv:
$ pip install -r healthchecks/requirements.txt
-
Create database tables and a superuser account:
$ cd ~/webapps/healthchecks $ ./manage.py migrate $ ./manage.py createsuperuser
With the default configuration, Healthchecks stores data in a SQLite file
hc.sqlite
in the checkout directory (~/webapps/healthchecks
).To use PostgreSQL or MySQL, see the section Database Configuration section below.
-
Run tests:
$ ./manage.py test
-
Run development server:
$ ./manage.py runserver
The site should now be running at http://localhost:8000
. To access Django administration site, log in as a superuser, then visit http://localhost:8000/admin/
Configuration
Healthchecks reads configuration from environment variables.
Full list of configuration parameters.
Accessing Administration Panel
Healthchecks comes with Django's administration panel where you can manually view and modify user accounts, projects, checks, integrations etc. To access it,
- if you haven't already, create a superuser account:
./manage.py createsuperuser
- log into the site using superuser credentials
- in the top navigation, "Account" dropdown, select "Site Administration"
Sending Emails
Healthchecks must be able to send email messages, so it can send out login links and alerts to users. Specify your SMTP credentials using the following environment variables:
EMAIL_HOST = "your-smtp-server-here.com"
EMAIL_PORT = 587
EMAIL_HOST_USER = "smtp-username"
EMAIL_HOST_PASSWORD = "smtp-password"
EMAIL_USE_TLS = True
For more information, have a look at Django documentation, Sending Email section.
Receiving Emails
Healthchecks comes with a smtpd
management command, which starts up a SMTP listener service. With the command running, you can ping your checks by sending email messages to [email protected]
email addresses.
Start the SMTP listener on port 2525:
$ ./manage.py smtpd --port 2525
Send a test email:
$ curl --url 'smtp://127.0.0.1:2525' \
--mail-from '[email protected]' \
--mail-rcpt '[email protected]' \
-F '='
Sending Status Notifications
healtchecks comes with a sendalerts
management command, which continuously polls database for any checks changing state, and sends out notifications as needed. Within an activated virtualenv, you can manually run the sendalerts
command like so:
$ ./manage.py sendalerts
In a production setup, you will want to run this command from a process manager like supervisor or systemd.
Database Cleanup
With time and use the Healthchecks database will grow in size. You may decide to prune old data: inactive user accounts, old checks not assigned to users, records of outgoing email messages and records of received pings. There are separate Django management commands for each task:
-
Remove old records from
api_ping
table. For each check, keep 100 most recent pings:$ ./manage.py prunepings
-
Remove old records of sent notifications. For each check, remove notifications that are older than the oldest stored ping for same check.
$ ./manage.py prunenotifications
-
Remove user accounts that match either of these conditions:
-
Account was created more than 6 months ago, and user has never logged in. These can happen when user enters invalid email address when signing up.
-
Last login was more than 6 months ago, and the account has no checks. Assume the user doesn't intend to use the account any more and would probably want it removed.
$ ./manage.py pruneusers
-
-
Remove old records from the
api_tokenbucket
table. The TokenBucket model is used for rate-limiting login attempts and similar operations. Any records older than one day can be safely removed.$ ./manage.py prunetokenbucket
-
Remove old records from the
api_flip
table. The Flip objects are used to track status changes of checks, and to calculate downtime statistics month by month. Flip objects from more than 3 months ago are not used and can be safely removed.$ ./manage.py pruneflips
When you first try these commands on your data, it is a good idea to test them on a copy of your database, not on the live database right away. In a production setup, you should also have regular, automated database backups set up.
Two-factor Authentication
Healthchecks optionally supports two-factor authentication using the WebAuthn standard. To enable WebAuthn support, set the RP_ID
(relying party identifier ) setting to a non-null value. Set its value to your site's domain without scheme and without port. For example, if your site runs on https://my-hc.example.org
, set RP_ID
to my-hc.example.org
.
Note that WebAuthn requires HTTPS, even if running on localhost. To test WebAuthn locally with a self-signed certificate, you can use the runsslserver
command from the django-sslserver
package.
External Authentication
Healthchecks supports external authentication by means of HTTP headers set by reverse proxies or the WSGI server. This allows you to integrate it into your existing authentication system (e.g., LDAP or OAuth) via an authenticating proxy. When this option is enabled, healtchecks will trust the header's value implicitly, so it is very important to ensure that attackers cannot set the value themselves (and thus impersonate any user). How to do this varies by your chosen proxy, but generally involves configuring it to strip out headers that normalize to the same name as the chosen identity header.
To enable this feature, set the REMOTE_USER_HEADER
value to a header you wish to authenticate with. HTTP headers will be prefixed with HTTP_
and have any dashes converted to underscores. Headers without that prefix can be set by the WSGI server itself only, which is more secure.
When REMOTE_USER_HEADER
is set, Healthchecks will:
- assume the header contains user's email address
- look up and automatically log in the user with a matching email address
- automatically create an user account if it does not exist
- disable the default authentication methods (login link to email, password)
Integrations
Slack
To enable the Slack "self-service" integration, you will need to create a "Slack App".
To do so:
- Create a new Slack app on https://api.slack.com/apps/
- Add at least one scope in the permissions section to be able to deploy the app in your workspace (By example
incoming-webhook
for theBot Token Scopes
https://api.slack.com/apps/APP_ID/oauth?). - Add a redirect url in the format
SITE_ROOT/integrations/add_slack_btn/
. For example, if your SITE_ROOT ishttps://my-hc.example.org
then the redirect URL would behttps://my-hc.example.org/integrations/add_slack_btn/
. - Look up your Slack app for the Client ID and Client Secret at https://api.slack.com/apps/APP_ID/general? . Put them in
SLACK_CLIENT_ID
andSLACK_CLIENT_SECRET
environment variables.
Discord
To enable Discord integration, you will need to:
- register a new application on https://discordapp.com/developers/applications/me
- add a redirect URI to your Discord application. The URI format is
SITE_ROOT/integrations/add_discord/
. For example, if you are running a development server onlocalhost:8000
then the redirect URI would behttp://localhost:8000/integrations/add_discord/
- Look up your Discord app's Client ID and Client Secret. Put them in
DISCORD_CLIENT_ID
andDISCORD_CLIENT_SECRET
environment variables.
Pushover
Pushover integration works by creating an application on Pushover.net which is then subscribed to by Healthchecks users. The registration workflow is as follows:
- On Healthchecks, the user adds a "Pushover" integration to a project
- Healthchecks redirects user's browser to a Pushover.net subscription page
- User approves adding the Healthchecks subscription to their Pushover account
- Pushover.net HTTP redirects back to Healthchecks with a subscription token
- Healthchecks saves the subscription token and uses it for sending Pushover notifications
To enable the Pushover integration, you will need to:
- Register a new application on Pushover via https://pushover.net/apps/build.
- Within the Pushover 'application' configuration, enable subscriptions. Make sure the subscription type is set to "URL". Also make sure the redirect URL is configured to point back to the root of the Healthchecks instance (e.g.,
http://healthchecks.example.com/
). - Put the Pushover application API Token and the Pushover subscription URL in
PUSHOVER_API_TOKEN
andPUSHOVER_SUBSCRIPTION_URL
environment variables. The Pushover subscription URL should look similar tohttps://pushover.net/subscribe/yourAppName-randomAlphaNumericData
.
Signal
Healthchecks uses signal-cli to send Signal notifications. Healthcecks interacts with signal-cli over DBus.
To enable the Signal integration:
- Set up and configure signal-cli to listen on DBus system bus (instructions). Make sure you can send test messages from command line, using the
dbus-send
example given in the signal-cli instructions. - Set the
SIGNAL_CLI_ENABLED
environment variable toTrue
.
Telegram
-
Create a Telegram bot by talking to the BotFather. Set the bot's name, description, user picture, and add a "/start" command.
-
After creating the bot you will have the bot's name and token. Put them in
TELEGRAM_BOT_NAME
andTELEGRAM_TOKEN
environment variables. -
Run
settelegramwebhook
management command. This command tells Telegram where to forward channel messages by invoking Telegram's setWebhook API call:$ ./manage.py settelegramwebhook Done, Telegram's webhook set to: https://my-monitoring-project.com/integrations/telegram/bot/
For this to work, your SITE_ROOT
needs to be correct and use "https://" scheme.
Apprise
To enable Apprise integration, you will need to:
- ensure you have apprise installed in your local environment:
pip install apprise
- enable the apprise functionality by setting the
APPRISE_ENABLED
environment variable.
Shell Commands
The "Shell Commands" integration runs user-defined local shell commands when checks go up or down. This integration is disabled by default, and can be enabled by setting the SHELL_ENABLED
environment variable to True
.
Note: be careful when using "Shell Commands" integration, and only enable it when you fully trust the users of your Healthchecks instance. The commands will be executed by the manage.py sendalerts
process, and will run with the same system permissions as the sendalerts
process.
Matrix
To enable the Matrix integration you will need to:
- Register a bot user (for posting notifications) in your preferred homeserver.
- Use the Login API call to retrieve bot user's access token. You can run it as shown in the documentation, using curl in command shell.
- Set the
MATRIX_
environment variables. Example:
MATRIX_HOMESERVER=https://matrix.org
MATRIX_USER_ID=@mychecks:matrix.org
MATRIX_ACCESS_TOKEN=[a long string of characters returned by the login call]
Running in Production
Here is a non-exhaustive list of pointers and things to check before launching a Healthchecks instance in production.
- Environment variables, settings.py and local_settings.py.
- DEBUG. Make sure it is set to
False
. - ALLOWED_HOSTS. Make sure it contains the correct domain name you want to use.
- Server Errors. When DEBUG=False, Django will not show detailed error pages, and will not print exception tracebacks to standard output. To receive exception tracebacks in email, review and edit the ADMINS and SERVER_EMAIL settings. Another good option for receiving exception tracebacks is to use Sentry.
- DEBUG. Make sure it is set to
- Management commands that need to be run during each deployment.
- This project uses Django Compressor to combine the CSS and JS files. It is configured for offline compression – run the
manage.py compress
command whenever files in the/static/
directory change. - This project uses Django's staticfiles app. Run the
manage.py collectstatic
command whenever files in the/static/
directory change. This command collects all the static files inside thestatic-collected
directory. Configure your web server to serve files from this directory under the/static/
prefix. - Database migration should be run after each update to make sure the database schemas are up to date. You can do that with
./manage.py migrate
.
- This project uses Django Compressor to combine the CSS and JS files. It is configured for offline compression – run the
- Processes that need to be running constantly.
manage.py runserver
is intended for development only. Do not use it in production, instead consider using uWSGI or gunicorn.- Make sure the
manage.py sendalerts
command is running and can survive server restarts. On modern linux systems, a good option is to define a systemd service for it.
- General
- Make sure the database is secured well and is getting backed up regularly
- Make sure the TLS certificates are secured well and are getting refreshed regularly
- Have monitoring in place to be sure the Healthchecks instance itself is operational (is accepting pings, is sending out alerts, is not running out of resources).