rss2world/app/app.go

126 lines
2.4 KiB
Go

package app
import (
"bytes"
"context"
"log/slog"
"os"
"text/template"
"time"
tgbotapi "github.com/go-telegram-bot-api/telegram-bot-api/v5"
"github.com/mmcdole/gofeed"
"gitrepo.ru/neonxp/rss2world/templates"
)
type App struct {
config *Config
telegram *tgbotapi.BotAPI
templates *template.Template
}
func New(cfg *Config) (*App, error) {
bot, err := tgbotapi.NewBotAPI(cfg.Telegram.BotToken)
if err != nil {
return nil, err
}
tpl, err := template.ParseFS(templates.Templates, "*.gotmpl")
if err != nil {
return nil, err
}
return &App{
config: cfg,
telegram: bot,
templates: tpl,
}, nil
}
func (a *App) Run(ctx context.Context) error {
ticker := time.NewTicker(a.config.RSS.CheckInterval)
for {
select {
case <-ctx.Done():
return nil
case <-ticker.C:
if err := a.iteration(); err != nil {
slog.ErrorContext(ctx, "failed iteration", slog.Any("error", err))
}
}
}
}
func (a *App) iteration() error {
seq, err := a.readSeqFile()
if os.IsNotExist(err) {
seq = ""
err = nil
}
if err != nil {
return err
}
items, err := a.findNewItems(seq)
if err != nil || len(items) == 0 {
return err
}
for i := len(items) - 1; i >= 0; i-- {
if err := a.processItem(items[i]); err != nil {
return err
}
if err := a.writeSeqFile(items[i].GUID); err != nil {
return err
}
}
return nil
}
func (a *App) processItem(item *gofeed.Item) error {
buf := bytes.NewBufferString("")
if err := a.templates.ExecuteTemplate(buf, "telegram", item); err != nil {
return err
}
for _, group := range a.config.Telegram.TargetGroups {
msg := tgbotapi.NewMessage(group, buf.String())
msg.ParseMode = tgbotapi.ModeHTML
if _, err := a.telegram.Send(msg); err != nil {
return err
}
}
return nil
}
func (a *App) readSeqFile() (string, error) {
seqVal, err := os.ReadFile(a.config.RSS.SeqFile)
if err != nil {
return "", err
}
return string(seqVal), nil
}
func (a *App) writeSeqFile(seqVal string) error {
return os.WriteFile(a.config.RSS.SeqFile, []byte(seqVal), 0644)
}
func (a *App) findNewItems(from string) ([]*gofeed.Item, error) {
fp := gofeed.NewParser()
feed, err := fp.ParseURL(a.config.RSS.URL)
if err != nil {
return nil, err
}
out := make([]*gofeed.Item, 0, len(feed.Items))
for _, item := range feed.Items {
if item.GUID == from {
break
}
out = append(out, item)
}
return out, nil
}