sentry

An URL monitoring alerting service.

Installing

Compile

This project requires go1.8+ to compile. Just run go get -u github.com/gesquive/sentry and the executable should be built for you automatically in your $GOPATH.

Optionally you can run make install to build and copy the executable to /usr/local/bin/ with correct permissions.

Download

Alternately, you can download the latest release for your platform from github.

Once you have an executable, make sure to copy it somewhere on your path like /usr/local/bin or C:/Program Files/. If on a *nix/mac system, make sure to run chmod +x /path/to/sentry.

Configuration

Precedence Order

The application looks for variables in the following order:

• command line flag
• environment variable
• config file variable
• default

So any variable specified on the command line would override values set in the environment or config file.

Config File

The application looks for a configuration file at the following locations in order:

• ./config.yml
• ~/.config/sentry/config.yml
• /etc/sentry/config.yml

Copy config.example.yml to one of these locations and populate the values with your own. Since the config could contain your SMTP username/password, make sure to set permissions on the config file appropriately so others cannot read it. A good suggestion is chmod 600 /path/to/config.yml.

If you are planning to run this app as a service/cronjob, it is recommended that you place the config in /etc/sentry/config.yml. Otherwise, if running from the command line, place the config in ~/.config/sentry/config.yml and make sure to set run_once: true.

Environment Variables

Optionally, instead of using a config file you can specify config entries as environment variables. Use the prefix "SENTRY_" in front of the uppercased variable name. For example, the config variable log_file would be the environment variable SENTRY_LOG_FILE.

Usage

Watches http/s URLs for unexpected responses.

Usage:
  sentry [flags]

Flags:
      --check                  Check the config for errors and exit
      --config string          Path to a specific config file (default "./config.yml")
  -l, --log-file string        Path to log file (default "/var/log/sentry.log")
  -n, --no-alerts              Disable all outgoing email alerts, log alerts only
      --run-once               Run once and print out target status
  -w, --smtp-password string   Authenticate the SMTP server with this password
  -o, --smtp-port uint32       The port to use for the SMTP server (default 25)
  -x, --smtp-server string     The SMTP server to send email through (default "localhost")
  -u, --smtp-username string   Authenticate the SMTP server with this user
  -v, --verbose                Print logs to stdout instead of file
      --version                Display the version number and exit

It is helpful to use the --run-once combined with the --verbose flags when first setting up to find any misconfigurations.

Optionally, a hidden debug flag is available in case you need additional output.

Hidden Flags:
  -D, --debug                  Include debug statements in log output

Cronjob

To run as a cronjob on an *nix system create a cronjob entry under the user the app is run with. If running as root, you can copy services/sentry.cron to /etc/cron.d/sentry or copy the following into you preferred crontab:

  0  *  *  *  * /usr/local/bin/sentry --run-once

Add any flags/env vars needed to make sure the job runs as intended. If not using arguments, then make sure the config file path is specified with a flag or can be found at one of the expected locations.

Service

By default, the process is setup to run as a service. Feel free to use upstart, init, runit or any other service manager to run the sentry executable.

Example systemd & upstart scripts can be found in the services directory.

Documentation

This documentation can be found at github.com/gesquive/sentry

License

This package is made available under an MIT-style license. See LICENSE.

Contributing

PRs are always welcome!