HTTP Monitor

Micro golang app for monitoring http endpoints.

http_monitor takes a path to a config file as the first argument, it proceeds to fetch the provided URLs, logging the response status code, as well as a breakdown of the request time.

Async processing

Go routines allows for the monitor keep track of every provided url in the provided intervals, without being influenced by bad endpoints taking too long to respond.

• time.AfterFunc: AfterFunc creates it's own go-routine after the provided time has passed, without holding up any processing, or being held up itself.

Setup:

1 - Create a config file: configs/config.json

[
  {
    "url": "http://www.google.com",
    "interval": 20
  },
  {
    "url": "http://www.yahoo.com",
    "interval": 10
  }
]

"interval" is measured in seconds, the minimum allowed value is 1

Local Setup

2 - Build the binary:

go build -o http_monitor.bin

3 - Run it!:

./http_monitor.bin ./configs/config.json

Docker Setup:

2 - Build the image:

docker build . --tag http-monitor

3 - Run it!:

docker run --rm -v /absolute/path/to/config.json:/app/config.json http-monitor

you need to provide a configFile to the container at:/app/config.json

Output

You should see some logs matching: [URL]: [Status Code] - [Request Time]. Followed by a break down of the total request time. Example:

[INFO] https://www.yahoo.com: 200 OK - 637.766229ms
DNS Lookup: 37.76337ms
Connection: 165.026824ms
TLS Handshake: 168.809246ms
Time to first byte: 637.608928ms