main.go

package main

import (
    "os"
    "log"
    "flag"
    "strconv"
    "path/filepath"
)

var (
    workflow = flag.String("workflow", "/usr/local/vamp/workflow.js", "Path to workflow file.")
    httpPort =  flag.Int("httpPort", 8080, "HTTP port.")
    uiPath = flag.String("uiPath", "./ui/", "Path to UI static content.")
    executionPeriod = flag.Int("executionPeriod", -1, "Period between successive executions in seconds (0 if disabled).")
    executionTimeout = flag.Int("executionTimeout", -1, "Maximum allowed execution time in seconds (0 if no timeout).")
    help = flag.Bool("help", false, "Print usage.")
)

func main() {
    log.SetFlags(log.Ldate | log.Ltime | log.LUTC | log.Lmicroseconds | log.Lshortfile)

    flag.Parse()

    if *help {
        flag.Usage()
        return
    }

    uiAbsPath, err := filepath.Abs(*uiPath)

    if err != nil {
        log.Fatal(err)
    }

    checkInt(executionPeriod, "VAMP_WORKFLOW_EXECUTION_PERIOD", "Execution period must be specified and it must be equal or greater than 0.")
    checkInt(executionTimeout, "VAMP_WORKFLOW_EXECUTION_TIMEOUT", "Execution timeout must be specified and it must be equal or greater than 0.")

    log.Println("HTTP port                 :", *httpPort)
    log.Println("HTTP static content path  :", uiAbsPath)
    log.Println("Workflow file path        :", *workflow)
    log.Println("Workflow execution period :", *executionPeriod)
    log.Println("Workflow execution timeout:", *executionTimeout)

    api := &Api{make(chan interface{})}

    go run(api, *workflow)
    serve(api, *httpPort, uiAbsPath)
}

func checkInt(argument *int, environmentVariable, panic string) {
    if *argument < 0 {
        number, err := strconv.Atoi(os.Getenv(environmentVariable))
        if err != nil {
            log.Fatal(panic)
        }
        *argument = number
        if *argument < 0 {
            log.Fatal(panic)
        }
    }
}