Quick and dirty Prowl API client in Go. You'd better use prowl libs on github, this is just my backup.

prowl.go

package main

import (
	"errors"
	"fmt"
	"io/ioutil"
	"log"
	"net/http"
	"net/url"
	"os"
	"path"
	"regexp"
	"strings"
)

const (
	PROWL_API = "https://api.prowlapp.com/publicapi/add"
	API_KEY_LENGTH = 40
)

type ProwlNotification struct {
	apiKey      string
	priority    string
	application string
	event       string
	description string
}

func NewProwlNotification() *ProwlNotification {
	return &ProwlNotification{priority: "0",
		application: "GoProwl",
		event:       "GoProwl notification"}
}

func (n ProwlNotification) FormParameters() url.Values {
	params := url.Values{}
	params.Add("apikey", n.apiKey)
	params.Add("priority", n.priority)
	params.Add("application", n.application)
	params.Add("event", n.event)
	params.Add("description", n.description)
	return params
}

func (n ProwlNotification) Send() bool {
	resp, err := http.PostForm(PROWL_API, n.FormParameters())
	defer resp.Body.Close()
	if err != nil {
		log.Fatal(err)
		return false
	}

	body, err := ioutil.ReadAll(resp.Body)
	if err != nil {
		log.Fatal(err)
		return false
	}
	// Well, no I'm not parsing XML to check thoses responses. BOOH!
	matched, err := regexp.Match("<success code=\"200\" ", body)
	if err != nil || !matched {
		if err != nil {
			log.Fatal(err)
		}
		return false
	}

	return true
}

/**
 * Read the user's API key from ~/.prowlrc, and complain if the file
 * can't be read, or does not seem to contain an API key.
 */
func ReadAPIKey() (apiKey string, err error) {
	filename := os.Getenv("HOME")
	file, err := os.Open(path.Join(filename, ".prowlrc"))
	if err != nil {
		return "", err
	}

	buf := make([]byte, API_KEY_LENGTH)
	count, err := file.Read(buf)
	if err != nil {
		return "", err
	}

	if count != API_KEY_LENGTH {
		return "", errors.New("Invalid API key")
	}

	apiKey = string(buf)
	return apiKey, err
}

func main() {
	apiKey, err := ReadAPIKey()
	if err != nil {
		fmt.Println("Can not read ~/.prowlrc file, make sure it exists ",
			"and contains an API key.")
		log.Fatal(err)
	}

	if 2 > len(os.Args) {
		fmt.Println("Message needed!")
		return
	}

	notif := NewProwlNotification()
	notif.apiKey = apiKey
	notif.description = strings.Join(os.Args[1:len(os.Args)], " ")
	if notif.Send() {
		fmt.Println("ok")
	} else {
		fmt.Println("ko")
	}
}