git » chasquid » commit 08273ea

diff --git a/internal/protoio/protoio.go b/internal/protoio/protoio.go
index b6bdd79..77df2f3 100644
--- a/internal/protoio/protoio.go
+++ b/internal/protoio/protoio.go
@@ -33,13 +33,13 @@ func ReadTextMessage(fname string, pb proto.Message) error {
 }
 
 // WriteMessage marshals pb and atomically writes it into fname.
-func WriteMessage(fname string, pb proto.Message, perm os.FileMode) error {
+func WriteMessage(fname string, pb proto.Message, perm os.FileMode, ops ...safeio.FileOp) error {
 	out, err := proto.Marshal(pb)
 	if err != nil {
 		return err
 	}
 
-	return safeio.WriteFile(fname, out, perm)
+	return safeio.WriteFile(fname, out, perm, ops...)
 }
 
 var textOpts = prototext.MarshalOptions{
@@ -48,12 +48,12 @@ var textOpts = prototext.MarshalOptions{
 
 // WriteTextMessage marshals pb in text format and atomically writes it into
 // fname.
-func WriteTextMessage(fname string, pb proto.Message, perm os.FileMode) error {
+func WriteTextMessage(fname string, pb proto.Message, perm os.FileMode, ops ...safeio.FileOp) error {
 	out, err := textOpts.Marshal(pb)
 	if err != nil {
 		return err
 	}
-	return safeio.WriteFile(fname, out, perm)
+	return safeio.WriteFile(fname, out, perm, ops...)
 }
 
 ///////////////////////////////////////////////////////////////
diff --git a/internal/queue/queue.go b/internal/queue/queue.go
index 0b177d4..202f6f4 100644
--- a/internal/queue/queue.go
+++ b/internal/queue/queue.go
@@ -25,6 +25,7 @@ import (
 	"blitiri.com.ar/go/chasquid/internal/expvarom"
 	"blitiri.com.ar/go/chasquid/internal/maillog"
 	"blitiri.com.ar/go/chasquid/internal/protoio"
+	"blitiri.com.ar/go/chasquid/internal/safeio"
 	"blitiri.com.ar/go/chasquid/internal/set"
 	"blitiri.com.ar/go/chasquid/internal/trace"
 	"blitiri.com.ar/go/log"
@@ -306,7 +307,10 @@ func (item *Item) WriteTo(dir string) error {
 
 	path := fmt.Sprintf("%s/%s%s", dir, itemFilePrefix, item.ID)
 
-	return protoio.WriteTextMessage(path, &item.Message, 0600)
+	// Write the file in text format for ease of debugging, and use fsync to
+	// improve durability.
+	return protoio.WriteTextMessage(
+		path, &item.Message, 0600, safeio.FsyncFileOp)
 }
 
 // SendLoop repeatedly attempts to send the item.
diff --git a/internal/safeio/safeio.go b/internal/safeio/safeio.go
index 31ad2a4..8115ade 100644
--- a/internal/safeio/safeio.go
+++ b/internal/safeio/safeio.go
@@ -95,3 +95,21 @@ func getOwner(fname string) (uid, gid int) {
 
 	return
 }
+
+// FsyncFileOp returns a FileOp that fsyncs the given file.
+// It would be even better if we would do this on the open file, but
+// unfortunately we don't have the API for it just yet. This should be good
+// enough for most cases on modern filesystems anyway.
+func FsyncFileOp(fname string) error {
+	f, err := os.OpenFile(fname, os.O_RDWR, 0)
+	if err != nil {
+		return err
+	}
+
+	if err = f.Sync(); err != nil {
+		f.Close()
+		return err
+	}
+
+	return f.Close()
+}
diff --git a/internal/safeio/safeio_test.go b/internal/safeio/safeio_test.go
index 021619e..574a7be 100644
--- a/internal/safeio/safeio_test.go
+++ b/internal/safeio/safeio_test.go
@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"errors"
 	"fmt"
+	"io/fs"
 	"os"
 	"strings"
 	"testing"
@@ -244,3 +245,30 @@ func checkNotExists(t *testing.T, fname string) {
 		t.Fatalf("file %v exists", fname)
 	}
 }
+
+func TestFsyncFileOp(t *testing.T) {
+	// Check it as an operation on a normal file.
+	dir := testlib.MustTempDir(t)
+	defer testlib.RemoveIfOk(t, dir)
+
+	content := []byte("content 1")
+	err := testWriteFile("file1", content, 0660, FsyncFileOp)
+	if err != nil {
+		t.Error(err)
+	}
+
+	// Use a file that doesn't exist to trigger an Open error.
+	err = FsyncFileOp("doesnotexist")
+	if !errors.Is(err, fs.ErrNotExist) {
+		t.Errorf("expected an fs.ErrNotExist, got %#v", err)
+	}
+
+	// To trigger a Sync error, we use /dev/null, which is writable but cannot
+	// be synced. Confirm the error is a fs.PathError and comes from the sync
+	// operation, to make sure we're not accidentally failing on Open or
+	// Close.
+	err = FsyncFileOp("/dev/null")
+	if pe, ok := err.(*fs.PathError); !ok || pe.Op != "sync" {
+		t.Errorf("expected a fs.PathError from sync, got %#v", err)
+	}
+}