'Exec' as an alternative to 'Url'

1 files changed, 39 insertions, 8 deletions

diff --git a/internal/feed/parse.go b/internal/feed/parse.go
index a8f705a..77dfe69 100644
--- a/internal/feed/parse.go
+++ b/internal/feed/parse.go
@@ -2,6 +2,8 @@ package feed
 
 import (
 	"fmt"
+	"io"
+	"os/exec"
 
 	"github.com/google/uuid"
 	"github.com/mmcdole/gofeed"
@@ -13,15 +15,44 @@ import (
 func (feed *Feed) parse() error {
 	fp := gofeed.NewParser()
 
-	// we do not use the http support in gofeed, so that we can control the behavior of http requests
-	// and ensure it to be the same in all places
-	resp, cancel, err := http.Get(feed.Url, feed.Global.Timeout, feed.NoTLS)
-	if err != nil {
-		return fmt.Errorf("while fetching %s from %s: %w", feed.Name, feed.Url, err)
+	var reader io.Reader
+	var cleanup func() error
+
+	if feed.Url != "" {
+		// we do not use the http support in gofeed, so that we can control the behavior of http requests
+		// and ensure it to be the same in all places
+		resp, cancel, err := http.Get(feed.Url, feed.Global.Timeout, feed.NoTLS)
+		if err != nil {
+			return fmt.Errorf("while fetching %s from %s: %w", feed.Name, feed.Url, err)
+		}
+		defer cancel() // includes resp.Body.Close
+
+		reader = resp.Body
+		cleanup = func() error { return nil }
+	} else { // exec
+		// we use the same context as for HTTP
+		ctx, cancel := http.Context(feed.Global.Timeout)
+		cmd := exec.CommandContext(ctx, feed.Exec[0], feed.Exec[1:]...)
+		defer func() {
+			cancel()
+			// cmd.Wait might have already been called -- but call it again to be sure
+			_ = cmd.Wait()
+		}()
+
+		stdout, err := cmd.StdoutPipe()
+		if err != nil {
+			return fmt.Errorf("preparing exec for feed '%s': %w", feed.Name, err)
+		}
+
+		if err = cmd.Start(); err != nil {
+			return fmt.Errorf("starting exec for feed '%s: %w", feed.Name, err)
+		}
+
+		reader = stdout
+		cleanup = cmd.Wait
 	}
-	defer cancel() // includes resp.Body.Close
 
-	parsedFeed, err := fp.Parse(resp.Body)
+	parsedFeed, err := fp.Parse(reader)
 	if err != nil {
 		return fmt.Errorf("parsing feed '%s': %w", feed.Name, err)
 	}
@@ -31,7 +62,7 @@ func (feed *Feed) parse() error {
 	for idx, feedItem := range parsedFeed.Items {
 		feed.items[idx] = item{Feed: parsedFeed, Item: feedItem, itemId: uuid.New(), feed: feed}
 	}
-	return nil
+	return cleanup()
 }
 
 func handleFeed(feed *Feed) {