tailer struct was incorrect and used incorrect channel

internal/cache/cache_test.go

@@ -5,6 +5,7 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"log/slog"
 	"net/http"
 	"net/http/httptest"
 	"os"
@@ -22,6 +23,8 @@ func newTestServer(t *testing.T, handler http.HandlerFunc) *httptest.Server {
 
 func newTestCache(t *testing.T, mirrorURLs []string) *Cache {
 	t.Helper()
+	// set slog to debug
+	slog.SetLogLoggerLevel(slog.LevelDebug)
 	mirroredRepos := []string{"core", "extra"}
 	c, err := NewCache(t.TempDir(), mirrorURLs, mirroredRepos)
 	if err != nil {
@@ -33,7 +36,6 @@ func newTestCache(t *testing.T, mirrorURLs []string) *Cache {
 
 func TestCacheHit(t *testing.T) {
 	const expected = "This is fake file contents"
-
 	c := newTestCache(t, []string{"http://example.com/"})
 	tmpFileName := "fakeFile"
 	err := c.cr.WriteFile(tmpFileName, []byte(expected), 0644)
@@ -78,10 +80,12 @@ func TestCacheMissExists(t *testing.T) {
 
 	c := newTestCache(t, []string{svr.URL + "/"})
 
-	_, err := c.Fetch("fakefile")
+	cf, err := c.Fetch("fakefile")
 	if err != nil {
 		t.Fatalf("Fetch failed %v", err)
 	}
+	io.Copy(io.Discard, cf.Reader)
+	cf.Reader.Close()
 
 	data, err := c.cr.ReadFile("fakefile")
 	if err != nil {

internal/cache/download.go

@@ -9,6 +9,8 @@ import (
 )
 
 func (c *Cache) downloadWrangle(relPath string, flight *inFlight, tmpFile *os.File) {
+
+	slog.Debug("wrangle starting", "relPath", relPath)
 	// defer map cleanup and signal client handle done
 	defer c.cleanupFlight(relPath, flight)
 
@@ -37,6 +39,7 @@ func (c *Cache) downloadWrangle(relPath string, flight *inFlight, tmpFile *os.Fi
 		}
 		return
 	}
+	slog.Debug("wrangle download complete", "err", err)
 
 	// mv file to final location
 	err = c.cr.Rename(flight.tmpPath, relPath)
@@ -47,7 +50,7 @@ func (c *Cache) downloadWrangle(relPath string, flight *inFlight, tmpFile *os.Fi
 		}
 		return
 	}
-	return
+	slog.Debug("file moved to final location", "err", err)
 }
 
 func (c *Cache) downloadToDisk(url string, tmpFile *os.File) error {
@@ -79,6 +82,9 @@ func (c *Cache) downloadToDisk(url string, tmpFile *os.File) error {
 	if err != nil {
 		return err
 	}
+	if err = tmpFile.Sync(); err != nil {
+		return err
+	}
 	return nil
 }
 
@@ -86,5 +92,6 @@ func (c *Cache) cleanupFlight(key string, f *inFlight) {
 	c.inFlightMu.Lock()
 	delete(c.inFlight, key)
 	c.inFlightMu.Unlock()
+	slog.Debug("closing done channel")
 	close(f.done)
 }

internal/cache/get_stream.go

@@ -35,6 +35,7 @@ func (c *Cache) getStream(relPath string) (*inFlight, *os.File, error) {
 
 	flight := &inFlight{
 		tmpPath: tmpPath,
+		done:    make(chan struct{}),
 	}
 
 	c.inFlight[relPath] = flight

internal/cache/refresh.go

@@ -19,7 +19,7 @@ func (c *Cache) Refresh() error {
 func (c *Cache) refreshDB(repo string) error {
 	dbFile := repo + ".db.tar.gz"
 	dbPath := filepath.Join(repo, "os/x86_64", dbFile)
-	err := c.getStream(dbPath)
+	_, _, err := c.getStream(dbPath)
 	if err != nil {
 		return err
 	}

internal/cache/tailer.go

@@ -2,31 +2,32 @@ package cache
 
 import (
 	"io"
+	"log/slog"
 	"os"
 	"time"
 )
 
 type tailer struct {
 	f      *os.File
-	done   <-chan struct{}
 	flight *inFlight
 }
 
 func (t *tailer) Read(p []byte) (int, error) {
 	for {
 		n, err := t.f.Read(p)
+		slog.Debug("tailer read", "n", n, "err", err)
 		if n > 0 {
 			return n, nil
 		}
 		if err == io.EOF {
 			select {
-			case <-t.done:
+			case <-t.flight.done:
 				if t.flight.err != nil {
 					return 0, t.flight.err
 				}
 				return t.f.Read(p) // send remainiing bytes
-			default:
-				time.Sleep(50 * time.Millisecond)
+			case <-time.After(50 * time.Millisecond):
+				slog.Debug("tailer waiting for more data")
 				continue
 			}
 		}