helios/tools/slack.go

package tools

import (
	"bytes"
	"context"
	"encoding/json"
	"errors"
	"fmt"
	"net/http"
	"time"
)

type (
	slackClient struct {
		address   string
		timeout   time.Duration
		username  string
		iconEmoji string
		iconURL   string
		channel   string
	}
	slackmessage struct {
		c         *slackClient
		Text      string               `json:"text"`
		// Markdown  string               `json:"markdown_text"`
		Username  string               `json:"username,omitempty"`
		IconEmoji string               `json:"icon_emoji,omitempty"`
		IconURL   string               `json:"icon_url,omitempty"`
		Channel   string               `json:"channel,omitempty"`
		Blocks    []*slackmessageblock `json:"blocks"`
	}
	slackmessageblock struct {
		Type string                `json:"type"`
		Text slackmessageblocktext `json:"text"`
	}
	slackmessageblocktext struct {
		Type string `json:"type"`
		Text string `json:"text"`
	}
)

func Slack(url string) *slackClient {
	return &slackClient{
		address: url,
	}
}

func (s *slackClient) Message(text string) *slackmessage {
	return &slackmessage{
		c:         s,
		Text:      text,
		Username:  "bot",
		IconEmoji: ":ghost:",
	}
}

// func (s *slackClient) MessageMarkdown(text string) *slackmessage {
// 	return &slackmessage{
// 		c:         s,
// 		Markdown:  text,
// 		Username:  "bot",
// 		IconEmoji: ":ghost:",
// 	}
// }

func (m *slackmessage) Block(text string) *slackmessageblock {
	block := &slackmessageblock{
		Type: "section",
		Text: slackmessageblocktext{
			Type: "mrkdwn",
			Text: text,
		},
	}

	if m.Blocks == nil {
		m.Blocks = []*slackmessageblock{}
	}

	m.Blocks = append(m.Blocks, block)

	return block
}

func (m *slackmessage) Send() (err error) {
	reqBody, _ := json.Marshal(m) //nolint:errchkjson

	r, nerr := http.NewRequestWithContext(context.TODO(), http.MethodPost, m.c.address, bytes.NewReader(reqBody))
	if nerr != nil {
		return fmt.Errorf("create request: %w", nerr)
	}

	r.Header.Set("Content-Type", "application/json; charset=utf-8")

	hr := http.DefaultClient

	resp, derr := hr.Do(r)
	if derr != nil {
		return fmt.Errorf("execute request: %w", derr)
	}

	defer func() {
		err = errors.Join(err, resp.Body.Close())
	}()

	if resp.StatusCode != http.StatusOK {
		return fmt.Errorf("unable to send the message- Code: %v, Status: %v", resp.StatusCode, resp.Status)
	}

	return nil
}