Slack auto inviter

main.go

package main

import (
	"fmt"
	"io"
	"io/ioutil"
	"log"
	"net/http"
	"net/url"
	"os"
	"time"
)

var slack_team, slack_api_key, slack_channels string

func init() {
	if slack_team = os.Getenv("SLACK_TEAM"); slack_team == "" {
		log.Fatal("Need to set SLACK_TEAM env var with slack subdomain: (***.slack.com)")
	}
	if slack_api_key = os.Getenv("SLACK_KEY"); slack_api_key == "" {
		log.Fatal("Need to set SLACK_KEY env var with slack api key generated via web.")
	}
	if slack_channels = os.Getenv("SLACK_CHANS"); slack_channels == "" {
		log.Fatal("Need to set SLACK_CHANS env var. ")
	}
}

func main() {

	http.HandleFunc("/", sendInvite)

	http.ListenAndServe(":8888", nil)
}

func sendInvite(w http.ResponseWriter, r *http.Request) {
	var fname, lname, email string
	if fname = r.FormValue("first_name"); fname == "" {
		w.WriteHeader(400)
		io.WriteString(w, "first_name required")
		return
	}
	if lname = r.FormValue("last_name"); lname == "" {
		w.WriteHeader(400)
		io.WriteString(w, "last_name required")
		return
	}
	if email = r.FormValue("email"); email == "" {
		w.WriteHeader(400)
		io.WriteString(w, "email required")
		return
	}
	u := fmt.Sprintf("https://%s.slack.com/api/users.admin.invite?t=%d", slack_team, time.Now().Unix())
	resp, err := http.PostForm(u,
		url.Values{
			"email":      {email},
			"channels":   {slack_channels},
			"first_name": {fname},
			"last_name":  {lname},
			"token":      {slack_api_key},
			"set_active": {"true"},
			"_attempts":  {"1"},
		})
	if err != nil {
		fmt.Println(err)
		return
	}
	w.WriteHeader(resp.StatusCode)

}