Segment

Segment.io compatible server written in go.

Introduction

Segment is a cloud based analytics platform for tracking events from your application.

It has a well designed specific that supports APIs:

• Page: what web page are they on?
• Track: what are they doing?
• Identify: who is the customer?
• Alias: what was their past identity?
• Group: what account or organization are they part of?
• Screen: what app screen are they on?

This go library implements endpoints for all of these APIs.

Getting Started

These instructions will get you a copy of the project up and running on your local machine for development and testing purposes. See deployment for notes on how to deploy the project on a live system.

Prerequisites

This library uses the gorilla mux library for attaching http handlers, and prometheus for monitoring.

go get -u github.com/gorilla/mux
go get -u github.com/prometheus/client_golang

Installing

This library is installed as package segment.

go get -u  github.com/brightsparc/segment

Examples

Create a new Segment listener by providing a function to return projectId from writeKey. For unknown writeKey values, return empty string to have endpoint return 400 back request. Configure one or more destinations, this example includes forwarded to segment cloud, and firehose stream.

package main

import (
	"context"
	"log"
	"net/http"

	"github.com/brightsparc/segment"

	"github.com/gorilla/mux"
	"github.com/prometheus/client_golang/prometheus/promhttp"
)

func main() {
	projectId := func(writeKey string) string {
		return "xxxx" // TODO: Match this with your writeKey for authorisation
	}
	destinations := []segment.Destination{
		segment.NewForwarder("https://api.segment.io/v1/batch"),
		segment.NewDelivery(&segment.DeliveryConfig{
			StreamRegion: "us-west-2",
			StreamName:   "stream-name", // Will attempt to create if not exists
		}),
	}

	router := mux.NewRouter()
	router.Handle("/metrics", promhttp.Handler()) // prometheus metrics endpoint
	sr := router.PathPrefix("/v1").Subrouter()    // Will create endpoints /v1/batch etc
	seg := segment.NewSegment(projectId, destinations, sr)
	go seg.Run(context.Background())

	log.Println("Listening on :8000")
	log.Fatal(http.ListenAndServe(":8000", router))
}

Implementation Details

Send messages

The segment Send method will execute Send method on each destination in order, and return on error. It is recommended to implement a queue as per the Delivery process, the Forwarder should only be used for testing.

Background process

• The segment Run method launches a go-routine for each destination, accepts a context to end these processes.
• The Delivery process attempts to connect to a region + stream, and optionally accepts an endpoint for testing. It requires AWS credentials to be set, and exit after 3 failed attempts. Batches of up to 500 messages at send every 30 seconds by default.

Logging

The Segment class will log to standard error by default, but can be configured by the Logger property.

Monitoring

The prometheus client is enabled to return http and delivery metrics.

Authors

• Julian Bright - brightsparc

License

This project is licensed under the MIT License - see the LICENSE.md file for details