1 files changed, 95 insertions, 0 deletions
diff --git a/internal/source/feed.go b/internal/source/feed.go
new file mode 100644
index 0000000..31f8535
--- /dev/null
+++ b/internal/source/feed.go
@@ -0,0 +1,95 @@
+package source
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"log/slog"
+	"time"
+
+	"github.com/mmcdole/gofeed"
+	cm "go.neonxp.ru/conf/model"
+	"go.neonxp.ru/pose/internal/model"
+)
+
+var (
+	ErrNoFeedAddress = errors.New("no feed address")
+)
+
+type Feed struct {
+	logger         *slog.Logger
+	feed           string
+	scrapeInterval time.Duration
+	feedParser     *gofeed.Parser
+}
+
+func NewFeed(cfg cm.Group, logger *slog.Logger) (*Feed, error) {
+	feedSource := cfg.Get("url").String()
+	if feedSource == "" {
+		return nil, ErrNoFeedAddress
+	}
+	durStr := cfg.Get("scrape_interval").String()
+	if durStr == "" {
+		durStr = "10m"
+	}
+	dur, err := time.ParseDuration(durStr)
+	if err != nil {
+		return nil, fmt.Errorf("failed parse duration at source: %w", err)
+	}
+	return &Feed{
+		feed:           feedSource,
+		scrapeInterval: dur,
+		feedParser:     gofeed.NewParser(),
+	}, nil
+}
+
+func (a *Feed) Retrive(ctx context.Context) <-chan model.Item {
+	out := make(chan model.Item)
+	ticker := time.NewTicker(a.scrapeInterval)
+	go func() {
+		<-ctx.Done()
+		ticker.Stop()
+	}()
+	go func() {
+		defer close(out)
+		for _, item := range a.scrapeFeed(ctx) {
+			out <- item
+		}
+		for range ticker.C {
+			for _, item := range a.scrapeFeed(ctx) {
+				out <- item
+			}
+		}
+	}()
+
+	return out
+}
+
+func (a *Feed) scrapeFeed(ctx context.Context) []model.Item {
+	feed, err := a.feedParser.ParseURLWithContext(a.feed, ctx)
+	if err != nil {
+		a.logger.Error("failed parse feed", slog.Any("err", err))
+		return nil
+	}
+	result := make([]model.Item, 0, len(feed.Items))
+	for _, it := range feed.Items {
+		date := time.Now()
+		if it.PublishedParsed != nil {
+			date = *it.PublishedParsed
+		}
+		image := ""
+		if it.Image != nil {
+			image = it.Image.URL
+		}
+		result = append(result, model.Item{
+			ID:      it.GUID,
+			Date:    date,
+			Title:   it.Title,
+			Summary: it.Description,
+			Link:    it.Link,
+			Img:     image,
+		})
+	}
+
+	return result
+}