fs/hash: align hashsum names and update documentation (#5339)

- Unify all hash names as lowercase alphanumerics without punctuation.
- Legacy names continue to work but disappear from docs, they can be depreciated or dropped later.
- Make rclone hashsum print supported hash list in case of wrong spelling.
- Update documentation.

Fixes #5071
Fixes #4841

backend/dropbox/dropbox.go

@@ -138,7 +138,7 @@ func getOauthConfig(m configmap.Mapper) *oauth2.Config {
 
 // Register with Fs
 func init() {
-	DbHashType = hash.RegisterHash("DropboxHash", 64, dbhash.New)
+	DbHashType = hash.RegisterHash("dropbox", "DropboxHash", 64, dbhash.New)
 	fs.Register(&fs.RegInfo{
 		Name:        "dropbox",
 		Description: "Dropbox",

backend/mailru/mailru.go

@@ -80,7 +80,7 @@ var oauthConfig = &oauth2.Config{
 
 // Register with Fs
 func init() {
-	MrHashType = hash.RegisterHash("MailruHash", 40, mrhash.New)
+	MrHashType = hash.RegisterHash("mailru", "MailruHash", 40, mrhash.New)
 	fs.Register(&fs.RegInfo{
 		Name:        "mailru",
 		Description: "Mail.ru Cloud",

backend/onedrive/onedrive.go

@@ -93,7 +93,7 @@ var (
 
 // Register with Fs
 func init() {
-	QuickXorHashType = hash.RegisterHash("QuickXorHash", 40, quickxorhash.New)
+	QuickXorHashType = hash.RegisterHash("quickxor", "QuickXorHash", 40, quickxorhash.New)
 	fs.Register(&fs.RegInfo{
 		Name:        "onedrive",
 		Description: "Microsoft OneDrive",

cmd/hashsum/hashsum.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"fmt"
 	"os"
+	"strings"
 
 	"github.com/pkg/errors"
 	"github.com/rclone/rclone/cmd"
@@ -69,23 +70,17 @@ hashed locally enabling any hash for any remote.
 Run without a hash to see the list of all supported hashes, e.g.
 
     $ rclone hashsum
-    Supported hashes are:
-      * MD5
-      * SHA-1
-      * DropboxHash
-      * QuickXorHash
-
+` + hashListHelp("    ") + `
 Then
 
     $ rclone hashsum MD5 remote:path
+
+Note that hash names are case insensitive.
 `,
 	RunE: func(command *cobra.Command, args []string) error {
 		cmd.CheckArgs(0, 2, command, args)
 		if len(args) == 0 {
-			fmt.Printf("Supported hashes are:\n")
-			for _, ht := range hash.Supported().Array() {
-				fmt.Printf("  * %v\n", ht)
-			}
+			fmt.Print(hashListHelp(""))
 			return nil
 		} else if len(args) == 1 {
 			return errors.New("need hash type and remote")
@@ -93,6 +88,7 @@ Then
 		var ht hash.Type
 		err := ht.Set(args[0])
 		if err != nil {
+			fmt.Println(hashListHelp(""))
 			return err
 		}
 		fsrc := cmd.NewFsSrc(args[1:])
@@ -111,3 +107,14 @@ Then
 		return nil
 	},
 }
+
+func hashListHelp(indent string) string {
+	var help strings.Builder
+	help.WriteString(indent)
+	help.WriteString("Supported hashes are:\n")
+	for _, ht := range hash.Supported().Array() {
+		help.WriteString(indent)
+		fmt.Fprintf(&help, "  * %v\n", ht.String())
+	}
+	return help.String()
+}

docs/content/commands/rclone_hashsum.md

@@ -25,15 +25,20 @@ Run without a hash to see the list of all supported hashes, e.g.
 
     $ rclone hashsum
     Supported hashes are:
-      * MD5
-      * SHA-1
-      * DropboxHash
-      * QuickXorHash
+      * md5
+      * sha1
+      * whirlpool
+      * crc32
+      * dropbox
+      * mailru
+      * quickxor
 
 Then
 
     $ rclone hashsum MD5 remote:path
 
+Note that hash names are case insensitive.
+
 
 ```
 rclone hashsum <hash> remote:path [flags]

fs/hash/hash.go

@@ -20,25 +20,36 @@ type Type int
 type hashDefinition struct {
 	width    int
 	name     string
+	alias    string
 	newFunc  func() hash.Hash
 	hashType Type
 }
 
-var hashes []*hashDefinition
-var highestType Type = 1
+var (
+	type2hash  = map[Type]*hashDefinition{}
+	name2hash  = map[string]*hashDefinition{}
+	alias2hash = map[string]*hashDefinition{}
+	supported  = []Type{}
+)
 
 // RegisterHash adds a new Hash to the list and returns it Type
-func RegisterHash(name string, width int, newFunc func() hash.Hash) Type {
+func RegisterHash(name, alias string, width int, newFunc func() hash.Hash) Type {
+	hashType := Type(1 << len(supported))
+	supported = append(supported, hashType)
+
 	definition := &hashDefinition{
 		name:     name,
+		alias:    alias,
 		width:    width,
 		newFunc:  newFunc,
-		hashType: highestType,
+		hashType: hashType,
 	}
-	hashes = append(hashes, definition)
-	highestType = highestType << 1
 
-	return definition.hashType
+	type2hash[hashType] = definition
+	name2hash[name] = definition
+	alias2hash[alias] = definition
+
+	return hashType
 }
 
 // ErrUnsupported should be returned by filesystem,
@@ -63,31 +74,23 @@ var (
 )
 
 func init() {
-	MD5 = RegisterHash("MD5", 32, md5.New)
-	SHA1 = RegisterHash("SHA-1", 40, sha1.New)
-	Whirlpool = RegisterHash("Whirlpool", 128, whirlpool.New)
-	CRC32 = RegisterHash("CRC-32", 8, func() hash.Hash { return crc32.NewIEEE() })
+	MD5 = RegisterHash("md5", "MD5", 32, md5.New)
+	SHA1 = RegisterHash("sha1", "SHA-1", 40, sha1.New)
+	Whirlpool = RegisterHash("whirlpool", "Whirlpool", 128, whirlpool.New)
+	CRC32 = RegisterHash("crc32", "CRC-32", 8, func() hash.Hash { return crc32.NewIEEE() })
 }
 
 // Supported returns a set of all the supported hashes by
 // HashStream and MultiHasher.
 func Supported() Set {
-	var types []Type
-	for _, v := range hashes {
-		types = append(types, v.hashType)
-	}
-
-	return NewHashSet(types...)
+	return NewHashSet(supported...)
 }
 
 // Width returns the width in characters for any HashType
 func Width(hashType Type) int {
-	for _, v := range hashes {
-		if v.hashType == hashType {
-			return v.width
-		}
+	if hash := type2hash[hashType]; hash != nil {
+		return hash.width
 	}
-
 	return 0
 }
 
@@ -118,32 +121,29 @@ func StreamTypes(r io.Reader, set Set) (map[Type]string, error) {
 // The function will panic if the hash type is unknown.
 func (h Type) String() string {
 	if h == None {
-		return "None"
+		return "none"
 	}
-
-	for _, v := range hashes {
-		if v.hashType == h {
-			return v.name
-		}
+	if hash := type2hash[h]; hash != nil {
+		return hash.name
 	}
-
-	err := fmt.Sprintf("internal error: unknown hash type: 0x%x", int(h))
-	panic(err)
+	panic(fmt.Sprintf("internal error: unknown hash type: 0x%x", int(h)))
 }
 
-// Set a Type from a flag
+// Set a Type from a flag.
+// Both name and alias are accepted.
 func (h *Type) Set(s string) error {
-	if s == "None" {
+	if s == "none" || s == "None" {
 		*h = None
+		return nil
 	}
-
-	for _, v := range hashes {
-		if v.name == s {
-			*h = v.hashType
-			return nil
-		}
+	if hash := name2hash[strings.ToLower(s)]; hash != nil {
+		*h = hash.hashType
+		return nil
+	}
+	if hash := alias2hash[s]; hash != nil {
+		*h = hash.hashType
+		return nil
 	}
-
 	return errors.Errorf("Unknown hash type %q", s)
 }
 
@@ -159,23 +159,14 @@ func fromTypes(set Set) (map[Type]hash.Hash, error) {
 	if !set.SubsetOf(Supported()) {
 		return nil, errors.Errorf("requested set %08x contains unknown hash types", int(set))
 	}
-	var hashers = make(map[Type]hash.Hash)
+	hashers := map[Type]hash.Hash{}
 
-	types := set.Array()
-	for _, t := range types {
-		for _, v := range hashes {
-			if t != v.hashType {
-				continue
-			}
-
-			hashers[t] = v.newFunc()
-			break
-		}
-
-		if hashers[t] == nil {
-			err := fmt.Sprintf("internal error: Unsupported hash type %v", t)
-			panic(err)
+	for _, t := range set.Array() {
+		hash := type2hash[t]
+		if hash == nil {
+			panic(fmt.Sprintf("internal error: Unsupported hash type %v", t))
 		}
+		hashers[t] = hash.newFunc()
 	}
 
 	return hashers, nil

fs/hash/hash_test.go

@@ -156,16 +156,53 @@ func TestHashStreamTypes(t *testing.T) {
 
 func TestHashSetStringer(t *testing.T) {
 	h := hash.NewHashSet(hash.SHA1, hash.MD5)
-	assert.Equal(t, h.String(), "[MD5, SHA-1]")
+	assert.Equal(t, "[md5, sha1]", h.String())
 	h = hash.NewHashSet(hash.SHA1)
-	assert.Equal(t, h.String(), "[SHA-1]")
+	assert.Equal(t, "[sha1]", h.String())
 	h = hash.NewHashSet()
-	assert.Equal(t, h.String(), "[]")
+	assert.Equal(t, "[]", h.String())
 }
 
 func TestHashStringer(t *testing.T) {
 	h := hash.MD5
-	assert.Equal(t, h.String(), "MD5")
+	assert.Equal(t, "md5", h.String())
+	h = hash.SHA1
+	assert.Equal(t, "sha1", h.String())
 	h = hash.None
-	assert.Equal(t, h.String(), "None")
+	assert.Equal(t, "none", h.String())
+}
+
+func TestHashSetter(t *testing.T) {
+	var ht hash.Type
+
+	assert.NoError(t, ht.Set("none"))
+	assert.Equal(t, hash.None, ht)
+	assert.NoError(t, ht.Set("None"))
+	assert.Equal(t, hash.None, ht)
+
+	assert.NoError(t, ht.Set("md5"))
+	assert.Equal(t, hash.MD5, ht)
+	assert.NoError(t, ht.Set("MD5"))
+	assert.Equal(t, hash.MD5, ht)
+
+	assert.NoError(t, ht.Set("sha1"))
+	assert.Equal(t, hash.SHA1, ht)
+	assert.NoError(t, ht.Set("SHA-1"))
+	assert.Equal(t, hash.SHA1, ht)
+
+	assert.NoError(t, ht.Set("SHA1"))
+	assert.Equal(t, hash.SHA1, ht)
+	assert.NoError(t, ht.Set("Sha1"))
+	assert.Equal(t, hash.SHA1, ht)
+	assert.Error(t, ht.Set("Sha-1"))
+}
+
+func TestHashTypeStability(t *testing.T) {
+	assert.Equal(t, hash.Type(0), hash.None)
+	assert.Equal(t, hash.Type(1), hash.MD5)
+	assert.Equal(t, hash.Type(2), hash.SHA1)
+
+	assert.True(t, hash.Supported().Contains(hash.MD5))
+	assert.True(t, hash.Supported().Contains(hash.SHA1))
+	assert.False(t, hash.Supported().Contains(hash.None))
 }

fs/operations/operations_test.go

@@ -1206,10 +1206,10 @@ func TestListFormat(t *testing.T) {
 			Format: "2006-01-02T15:04:05.000000000Z07:00"},
 		IsDir: false,
 		Hashes: map[string]string{
-			"MD5":          "0cc175b9c0f1b6a831c399e269772661",
-			"SHA-1":        "86f7e437faa5a7fce15d1ddcb9eaeaea377667b8",
-			"DropboxHash":  "bf5d3affb73efd2ec6c36ad3112dd933efed63c4e1cbffcfa88e2759c144f2d8",
-			"QuickXorHash": "6100000000000000000000000100000000000000"},
+			"md5":      "0cc175b9c0f1b6a831c399e269772661",
+			"sha1":     "86f7e437faa5a7fce15d1ddcb9eaeaea377667b8",
+			"dropbox":  "bf5d3affb73efd2ec6c36ad3112dd933efed63c4e1cbffcfa88e2759c144f2d8",
+			"quickxor": "6100000000000000000000000100000000000000"},
 		ID:     "fileID",
 		OrigID: "fileOrigID",
 	}

fs/options_test.go

@@ -115,7 +115,7 @@ func TestHTTPOption(t *testing.T) {
 func TestHashesOption(t *testing.T) {
 	opt := &HashesOption{hash.Set(hash.MD5 | hash.SHA1)}
 	var _ OpenOption = opt // check interface
-	assert.Equal(t, `HashesOption([MD5, SHA-1])`, opt.String())
+	assert.Equal(t, `HashesOption([md5, sha1])`, opt.String())
 	key, value := opt.Header()
 	assert.Equal(t, "", key)
 	assert.Equal(t, "", value)