Correctly handle file updates in read only directories (fixes #470)

model/puller.go

@@ -436,9 +436,12 @@ func (p *puller) handleBlock(b bqBlock) bool {
 		of.temp = filepath.Join(p.repoCfg.Directory, defTempNamer.TempName(f.Name))
 
 		dirName := filepath.Dir(of.filepath)
-		_, err := os.Stat(dirName)
+		fi, err := os.Stat(dirName)
 		if err != nil {
 			err = os.MkdirAll(dirName, 0777)
+		} else {
+			// We need to make sure the directory is writeable so we can create files in it
+			err = os.Chmod(dirName, 0777)
 		}
 		if err != nil {
 			l.Infof("mkdir: error: %q / %q: %v", p.repoCfg.ID, f.Name, err)
@@ -597,7 +600,9 @@ func (p *puller) handleEmptyBlock(b bqBlock) {
 			l.Debugf("pull: delete %q", f.Name)
 		}
 		os.Remove(of.temp)
+		// Ensure the file and the directory it is in is writeable so we can remove the file
 		os.Chmod(of.filepath, 0666)
+		os.Chmod(filepath.Dir(of.filepath), 0777)
 		if p.versioner != nil {
 			if debug {
 				l.Debugln("pull: deleting with versioner")