luci-go/common/dirwalk: Code for walking a directory tree efficiently

common/dirwalk/tests/tools/walkdir/fileprocessor_hash.go

+// Copyright 2016 The LUCI Authors. All rights reserved.
+// Use of this source code is governed under the Apache License, Version 2.0
+// that can be found in the LICENSE file.
+
+package main
+
+import (
+        "fmt"
+        "io"
+)
+
+// HashFileProcessor implements FileProcessor. It generates a hash for the contents of each
+// found file.
+type HashFileProcessor struct {
+        BaseFileProcessor
+        obuf io.Writer
+}
+
+func (p *HashFileProcessor) HashedFile(path string, r io.Reader) {
+        digest, _, err := hash(r)
+        if err != nil {
+                p.Error(path, err)
+                return
+        }
+        fmt.Fprintf(p.obuf, "%s: %v\n", path, digest)
+}
+
+func (p *HashFileProcessor) SmallFile(path string, r io.ReadCloser) {
+        p.HashedFile(path, r)
+        p.BaseFileProcessor.SmallFile(path, r)
+}
+
+func (p *HashFileProcessor) LargeFile(path string, r io.ReadCloser) {
+        p.HashedFile(path, r)
+        p.BaseFileProcessor.LargeFile(path, r)
+}