autospotting.go

// Copyright (c) 2016-2019 Cristian Măgherușan-Stanciu
// Licensed under the Open Software License version 3.0

package main

import (
	"context"
	"encoding/json"
	"io/ioutil"
	"log"
	"os"

	autospotting "github.com/AutoSpotting/AutoSpotting/core"
	"github.com/aws/aws-lambda-go/lambda"
)

var as *autospotting.AutoSpotting
var conf autospotting.Config

// Version represents the build version being used
var Version = "number missing"

var eventFile string

func main() {
	eventFile = conf.EventFile

	if os.Getenv("AWS_LAMBDA_FUNCTION_NAME") != "" {
		lambda.Start(Handler)
	} else if eventFile != "" {
		parseEvent, err := ioutil.ReadFile(eventFile)
		if err != nil {
			log.Fatal(err)
		}
		Handler(context.TODO(), parseEvent)
	} else {
		eventHandler(nil)
	}
}

func eventHandler(event *json.RawMessage) {

	log.Println("Starting autospotting agent, build", Version)
	log.Printf("Configuration flags: %#v", conf)

	as.EventHandler(event)
	log.Println("Execution completed, nothing left to do")
}

// this is the equivalent of a main for when running from Lambda, but on Lambda
// the runFromCronEvent() is executed within the handler function every time we have an event
func init() {
	as = &autospotting.AutoSpotting{}

	conf = autospotting.Config{
		Version: Version,
	}

	autospotting.ParseConfig(&conf)
	as.Init(&conf)
}

// Handler implements the AWS Lambda handler interface
func Handler(ctx context.Context, rawEvent json.RawMessage) {
	eventHandler(&rawEvent)
}