Fix 500 errors on file routes when accessing a file that doesn't exist

server/filesystem.go

@@ -40,8 +40,8 @@ func IsPathResolutionError(err error) bool {
 }
 
 type Filesystem struct {
-	Server        *Server
-	cacheDiskMu   sync.Mutex
+	Server      *Server
+	cacheDiskMu sync.Mutex
 }
 
 // Returns the root path that contains all of a server's data.
@@ -424,7 +424,7 @@ func (fs *Filesystem) unsafeStat(p string) (*Stat, error) {
 	return st, nil
 }
 
-// Creates a new directory (name) at a specificied path (p) for the server.
+// Creates a new directory (name) at a specified path (p) for the server.
 func (fs *Filesystem) CreateDirectory(name string, p string) error {
 	cleaned, err := fs.SafePath(path.Join(p, name))
 	if err != nil {
@@ -540,7 +540,7 @@ func (fs *Filesystem) Copy(p string) error {
 	}
 
 	if s, err := os.Stat(cleaned); err != nil {
-		return err
+		return errors.WithStack(err)
 	} else if s.IsDir() || !s.Mode().IsRegular() {
 		// If this is a directory or not a regular file, just throw a not-exist error
 		// since anything calling this function should understand what that means.

server/filesystem_unarchive.go

@@ -73,6 +73,11 @@ func (fs *Filesystem) DecompressFile(dir string, file string) error {
 		return errors.WithStack(err)
 	}
 
+	// Make sure the file exists basically.
+	if _, err := os.Stat(source); err != nil {
+		return errors.WithStack(err)
+	}
+
 	// Walk over all of the files spinning up an additional go-routine for each file we've encountered
 	// and then extract that file from the archive and write it to the disk. If any part of this process
 	// encounters an error the entire process will be stopped.