notifier

notifier is a package for sending text messages to a server via HTTP POST method.

Exported methods:

• NewNotifier constructor for Notifier, receives a config.
• Start starts N workers, by default 20. Each worker creates a custom HTTP client with specified timeouts, used for sending messages.
• Send receives messages as []Message, adds them to a sending channel read by workers.
• Stop closes the sending channel and waits for the workers to complete the recent sending.
• ErrChan returns an error channel to read and handle failed messages.

Logging

The package uses github.com/sirupsen/logrus logger, logs as JSON to stdout. Log level can be set via LOG_LEVEL env variable, default is debug level. Logging has to be handled externally, see 12factor.net/logs.

Run tests

cd notifier/
go test -v

notify cli tool

notify is an utility to send text messages to a server using notifier package.

Usage

./notify --help
Usage of ./notify:
  -i int
        Notification interval, sec (shorthand) (default 5)
  -interval int
        Notification interval, sec (default 5)
  -url string
        Target server url for sending notifications

What it does internally

Parser reads stdin, wraps lines into a message and sends them to Sender via a channel. Sender takes messages from the channel, collects them into a local buffer and sends them at once on a time interval. HandleErrors receives failed messages from notifier package for further handling.

Graseful shutdown

notify listens for SIGINT, SIGTERM On signal, Sender will stop sending new messages and wait for notifier to complete.

Installation

cd cmd/notify/
go build 

Start a server

An example server that helps to demonstrate receiving messages from notify.

cd internal/server/
go run server.go 

Run an example

Basic debug messages will be printed in stdout.

./notify --url=http://localhost:8080/notify -i 1 < messages.txt