send_slack.go

package slack

import (
	"bytes"
	"encoding/json"
	"log"
	"net/http"
	"net/url"
	"os"
)

type payload struct {
	Channel   string `json:"channel"`
	Text      string `json:"text"`
	Username  string `json:"username"`
	IconEmoji string `json:"icon_emoji"`
	AsUser    bool   `json:"as_user"`
}

func SendSlack(message string) {
	req, err := createRequest(message)
	if err != nil {
		log.Printf(err)
		os.Exit(1)
	}

	client := http.Client{}
	resp, err := client.Do(req)
	if err != nil {
		log.Printf(err)
		os.Exit(1)
	}
	defer resp.Body.Close()
}

func createRequest(message string) (*http.Request, error) {
	channelID := os.Getenv("SLACK_CHANNEL")
	endpoint := os.Getenv("SLACK_ENDPOINT")

	data := payload{
		channelID,
		message,
		"botName",
		":ghost:",
		false,
	}
	jsonStr, err := json.Marshal(data)
	if err != nil {
		return nil, err
	}

	values := url.Values{}
	values.Set("payload", string(jsonStr))

	req, err := http.NewRequest(
		"POST",
		endpoint,
		bytes.NewBufferString(values.Encode()),
	)
	if err != nil {
		return nil, err
	}
	req.Header.Add("Content-Type", "application/x-www-form-urlencoded")
	return req, nil
}