image hashing to sha256

backend/app/store/image/image.go

@@ -2,7 +2,7 @@
 package image
 
 import (
-	"crypto/sha1"
+	"crypto/sha256"
 	"encoding/hex"
 	"fmt"
 	"hash/crc64"
@@ -42,7 +42,7 @@ type FileSystem struct {
 // Files partitioned across multiple subdirectories.
 func (f *FileSystem) Save(name string, r io.Reader) (id string, err error) {
 
-	h := sha1.Sum([]byte(name))
+	h := sha256.Sum224([]byte(name))
 	id = hex.EncodeToString(h[:])
 	if ext := path.Ext(name); ext != "" {
 		id += ext

backend/app/store/image/image_test.go

@@ -24,9 +24,9 @@ func TestImage_Save(t *testing.T) {
 	}
 	id, err := svc.Save("blah_ff1.png", strings.NewReader("blah blah"))
 	assert.NoError(t, err)
-	assert.Equal(t, "6851dcde6024e03258a66705f29e14b506048c74.png", id)
+	assert.Equal(t, "fc77a87ad3c898b9603119711f99305145e272e103c904d85ee2deda.png", id)
 
-	dst := path.Join(loc, "02", id)
+	dst := path.Join(loc, "56", id)
 	data, err := ioutil.ReadFile(dst)
 	assert.NoError(t, err)
 	assert.Equal(t, "blah blah", string(data))