lilin

Lilin is service monitoring for HTTP and TCP services.

Features,

• Monitoring HTTP, TCP, UDP services
• Sending notification when service up or down through,
  • Mattermost incoming webhook

Building

To build lilin program, you need Go compiler. Once you have installed and setup the Go compiler, run the following command to build the program,

$ go build ./cmd/lilin

The above command will create executable file named lilin in the current directory.

Command options

The lilin program has the following options,

-basedir:: set the base directory for reading main configuration, service configurations, and storing the service logs. If not defined, its default to "/".

Main configuration

Lilin read the main configuration from ${BASEDIR}etc/lilin/lilin.cfg. The configuration is written in INI file format.

The $BASEDIR variable can be changes during running lilin program with -basedir option. For example,

$ lilin -basedir ./monitoring

The lilin.cfg has the following format,

[server]
address =

address:: define the HTTP server address to view the status of monitored services from web browser, default to 127.0.0.1:14507.

Monitoring services

Lilin monitor the services by reading each service configuration inside the ${BASEDIR}etc/lilin/service.d/ directory. Each service configuration is written in INI file format and must have .cfg file extension.

The service configuration has the following format,

[service]
name =
address =
method =
timeout =
interval =

name:: The human readable service name.

address:: The address of service to be monitored, using scheme based. For example

• http://example.com/health for monitoring HTTP service,
• https://example.com:8443/health for monitoring HTTPS service,
• tcp://127.0.0.1:22 for monitoring TCP service,
• udp://127.0.0.1:53 for monitoring UDP service.

method:: The HTTP method to be used to inquiry the HTTP or HTTPS service, default to GET. Supported method are DELETE, GET, HEAD, PATCH, POST, or PUT.

timeout:: Timeout for connecting and reading the response, default to 5 seconds. Timeout format is using suffix s for second, m for minute, and h for hour.

interval:: Interval between each scan, default and minimum value is 10 seconds. Interval format is using suffix s for second, m for minute, and h for hour.

For example to monitor HTTP service at http://127.0.0.1:8080 every 5 minutes using HTTP method HEAD with timeout 60 seconds, create file named myhttp.cfg inside the $BASEDIR/etc/lilin/service.d/ directory with the following content,

[service]
name = myhttp
address = http://127.0.0.1:8080
method = HEAD
interval = 5m
timeout = 60s

Sample of service configuration that monitor TCP service at 127.0.0.1:5432 every 90 seconds with timeout 30 seconds,

[service]
name = my-tcp-service
address = tcp://127.0.0.1:5432
interval = 90s
timeout = 30s

Notification

Lilin support sending notification to,

• Mattermost using incoming webhook.

See the next section on how to use the notification.

Mattermost incoming webhook

In the main configuration, add the section "notif" with the following format,

[notif]
kind = mattermost
webhook_url = # The incoming webhook URL.
channel = # The channel where the notification will be placed.
down_template = # Message template when service is down.
up_template = # Message template when service is up.

The down_template and up_template can contains the following variables,

• .ID: the service ID
• .At: the time when service up or down
• .Error: the error message that cause the service marked as down

For example, given the following scan report value,

.ID: http-server
.At: 2025-09-26 06:38:11 +0000 UTC
.Error: 503 Service Unavailable

The following down_template

{{.At}}: Service {{.ID}} is down: {{.Error}}

will be rendered as

2025-09-26 06:38:11 +0000 UTC: Service http-server is down: 503 Service Unavailable

Links

Project page.

Repository -- The repository of this software project.

Mailing list -- Place for discussion and sending patches.

Issues -- Place to open new issue or request for new feature.

Changelog - Log for each release.