1 files changed, 48 insertions, 0 deletions
diff --git a/workhorse/internal/filestore/multi_hash.go b/workhorse/internal/filestore/multi_hash.go
new file mode 100644
index 00000000000..40efd3a5c1f
--- /dev/null
+++ b/workhorse/internal/filestore/multi_hash.go
@@ -0,0 +1,48 @@
+package filestore
+
+import (
+	"crypto/md5"
+	"crypto/sha1"
+	"crypto/sha256"
+	"crypto/sha512"
+	"encoding/hex"
+	"hash"
+	"io"
+)
+
+var hashFactories = map[string](func() hash.Hash){
+	"md5":    md5.New,
+	"sha1":   sha1.New,
+	"sha256": sha256.New,
+	"sha512": sha512.New,
+}
+
+type multiHash struct {
+	io.Writer
+	hashes map[string]hash.Hash
+}
+
+func newMultiHash() (m *multiHash) {
+	m = &multiHash{}
+	m.hashes = make(map[string]hash.Hash)
+
+	var writers []io.Writer
+	for hash, hashFactory := range hashFactories {
+		writer := hashFactory()
+
+		m.hashes[hash] = writer
+		writers = append(writers, writer)
+	}
+
+	m.Writer = io.MultiWriter(writers...)
+	return m
+}
+
+func (m *multiHash) finish() map[string]string {
+	h := make(map[string]string)
+	for hashName, hash := range m.hashes {
+		checksum := hash.Sum(nil)
+		h[hashName] = hex.EncodeToString(checksum)
+	}
+	return h
+}