fix: read yt-dlp progress from stdout instead of stderr; add explicit --proxy support

internal/dl/progress.go

@@ -98,22 +98,16 @@ func parseProgressLine(line string) *progressUpdate {
 	return u
 }
 
-// readProgress reads yt-dlp stderr and sends progress updates to the channel.
+// readProgress reads yt-dlp output and sends progress updates to the channel.
 // The caller is responsible for closing the updates channel.
-func readProgress(stderr io.ReadCloser, updates chan<- *domain.DownloadJob, job *domain.DownloadJob) {
-	var stderrBuf strings.Builder
-	scanner := bufio.NewScanner(stderr)
+func readProgress(reader io.ReadCloser, updates chan<- *domain.DownloadJob, job *domain.DownloadJob) {
+	scanner := bufio.NewScanner(reader)
 	lineCount := 0
 	matchCount := 0
 	for scanner.Scan() {
 		line := scanner.Text()
 		lineCount++
 
-		if stderrBuf.Len() < 4096 {
-			stderrBuf.WriteString(line)
-			stderrBuf.WriteByte('\n')
-		}
-
 		parsed := parseProgressLine(line)
 		if parsed == nil {
 			continue
@@ -124,6 +118,5 @@ func readProgress(stderr io.ReadCloser, updates chan<- *domain.DownloadJob, job
 		job.ETA = parsed.eta
 		updates <- job
 	}
-	job.StderrLog = stderrBuf.String()
-	slog.Info("readProgress finished", "url", job.URL, "lines", lineCount, "matches", matchCount, "stderr_len", len(job.StderrLog))
+	slog.Info("readProgress finished", "url", job.URL, "lines", lineCount, "matches", matchCount)
 }

internal/dl/ytdlp.go

@@ -5,6 +5,7 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
+	"io"
 	"log/slog"
 	"os"
 	"os/exec"
@@ -21,6 +22,7 @@ import (
 type Client struct {
 	binaryPath  string
 	cookiesFile string
+	proxyURL    string
 	cache       map[string]*cachedMediaInfo
 	cacheMu     sync.Mutex
 }
@@ -60,9 +62,19 @@ func NewClient(cookiesFile string) (*Client, error) {
 		return nil, fmt.Errorf("yt-dlp not found in PATH: %w", err)
 	}
 	slog.Info("yt-dlp found", "path", path)
+
+	proxyURL := os.Getenv("HTTP_PROXY")
+	if proxyURL == "" {
+		proxyURL = os.Getenv("HTTPS_PROXY")
+	}
+	if proxyURL != "" {
+		slog.Info("using proxy for yt-dlp", "proxy", proxyURL)
+	}
+
 	return &Client{
 		binaryPath:  path,
 		cookiesFile: cookiesFile,
+		proxyURL:    proxyURL,
 		cache:       make(map[string]*cachedMediaInfo),
 	}, nil
 }
@@ -118,6 +130,9 @@ func (c *Client) GetMediaInfo(url string) (*domain.MediaInfo, error) {
 	if c.cookiesFile != "" {
 		args = append(args, "--cookies", c.cookiesFile)
 	}
+	if c.proxyURL != "" {
+		args = append(args, "--proxy", c.proxyURL)
+	}
 
 	slog.Info("fetching media info", "url", url)
 	out, err := c.run(args)
@@ -184,6 +199,9 @@ func (c *Client) GetPlaylistInfo(url string) (*domain.MediaInfo, error) {
 	if c.cookiesFile != "" {
 		args = append(args, "--cookies", c.cookiesFile)
 	}
+	if c.proxyURL != "" {
+		args = append(args, "--proxy", c.proxyURL)
+	}
 
 	slog.Info("fetching playlist info", "url", url)
 	out, err := c.run(args)
@@ -297,6 +315,9 @@ func (c *Client) StartDownload(job *domain.DownloadJob, downloadDir string) (<-c
 	if c.cookiesFile != "" {
 		args = append(args, "--cookies", c.cookiesFile)
 	}
+	if c.proxyURL != "" {
+		args = append(args, "--proxy", c.proxyURL)
+	}
 
 	args = append(args, job.URL)
 
@@ -305,6 +326,13 @@ func (c *Client) StartDownload(job *domain.DownloadJob, downloadDir string) (<-c
 	cmd := exec.Command(c.binaryPath, args...)
 	cmd.Env = append(os.Environ(), "PYTHONUNBUFFERED=1")
 
+	// yt-dlp outputs [download] progress lines to stdout when saving to a file
+	// and to stderr when using -o -. Since we save to a file, read stdout for progress.
+	stdout, err := cmd.StdoutPipe()
+	if err != nil {
+		return nil, fmt.Errorf("create stdout pipe: %w", err)
+	}
+
 	stderr, err := cmd.StderrPipe()
 	if err != nil {
 		return nil, fmt.Errorf("create stderr pipe: %w", err)
@@ -329,10 +357,16 @@ func (c *Client) StartDownload(job *domain.DownloadJob, downloadDir string) (<-c
 
 		progressDone := make(chan struct{})
 		go func() {
-			readProgress(stderr, updates, job)
+			readProgress(stdout, updates, job)
 			close(progressDone)
 		}()
 
+		// Capture stderr (warnings, errors) for diagnostics
+		go func() {
+			slurp, _ := io.ReadAll(stderr)
+			job.StderrLog = string(slurp)
+		}()
+
 		// Wait for either completion or cancellation
 		done := make(chan error, 1)
 		go func() {
@@ -395,6 +429,9 @@ func (c *Client) SearchYoutube(query string) (url, title string, err error) {
 	if c.cookiesFile != "" {
 		args = append(args, "--cookies", c.cookiesFile)
 	}
+	if c.proxyURL != "" {
+		args = append(args, "--proxy", c.proxyURL)
+	}
 
 	out, err := c.run(args)
 	if err != nil {
@@ -428,6 +465,9 @@ func (c *Client) Search(query, source string, limit int) ([]domain.PlaylistEntry
 	if c.cookiesFile != "" {
 		args = append(args, "--cookies", c.cookiesFile)
 	}
+	if c.proxyURL != "" {
+		args = append(args, "--proxy", c.proxyURL)
+	}
 
 	slog.Info("searching", "query", query, "source", source)
 	out, err := c.run(args)