[Web service] program health report

Introduction

Hosted by laitos web server, the comprehensive report shows:

• System status:
  • Clock time, uptime.
  • System load, disk, and memory usage.
• Program status:
  • Public IP address, uptime.
  • Program environment, working directory.
  • Daemon requests statistics.
• Latest log entries and stack traces.

Configuration

Under JSON key HTTPHandlers, write a string property called InformationEndpoint, value being the URL location that will serve the report. Keep the location a secret to yourself and make it difficult to guess.

Here is an example setup:

{
    ...

    "HTTPHandlers": {
        ...
        "InformationEndpoint": "/very-secret-program-health-report",
        ...
    },

    ...
}

Run

The report is hosted by web server, therefore remember to run web server.

Usage

In a web browser, navigate to InformationEndpoint of laitos web server, and inspect the program health report in plain text.

Using a programmable HTTP client (e.g. curl), use the Accept: application/json to retrieve JSON-formatted response.

Tips

• Make the endpoint difficult to guess, this helps to prevent misuse of the service.
• laitos only keeps a small number of recent log entries in memory for inspection. Seek host OS's help to view more historical log entries.
• Some log messages are automatically discarded due to throttling, see also High request per second and logging