✨ [tus] Add utilities for generating header values (#731)

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### Description
- `[tus]` Add utilities for generating header values



### Test Coverage

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coverage of this change.
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- [x]  This change is covered by existing or additional automated tests.
- [ ] Manual testing has been performed (and evidence provided) as
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- [ ] Additional tests are not required for this change (e.g.
documentation update).

Author: acabarbaye

changes/20251017171656.feature

@@ -0,0 +1 @@
+:sparkles: `[tus]` Add utilities for generating header values

utils/http/headers/tus/tus.go

@@ -2,6 +2,7 @@ package tus
 
 import (
 	"context"
+	"fmt"
 	"net/url"
 	"regexp"
 	"strings"
@@ -16,6 +17,19 @@ import (
 
 const KeyTUSMetadata = "filename"
 
+// GenerateTUSChecksumHeader generate the checksum header value
+// See https://tus.io/protocols/resumable-upload#upload-checksum
+func GenerateTUSChecksumHeader(hashAlgo, hash string) (header string, err error) {
+	hashAlgoC, err := hashing.DetermineHashingAlgorithmCanonicalReference(hashAlgo)
+	if err != nil {
+		err = commonerrors.WrapError(commonerrors.ErrUnsupported, err, "hashing algorithm is not supported")
+		return
+	}
+	base64Hash := base64.EncodeString(hash)
+	header = fmt.Sprintf("%v %v", strings.ToLower(hashAlgoC), base64Hash)
+	return
+}
+
 // ParseTUSHash parses the checksum header value and tries to determine the different elements it contains.
 // See https://tus.io/protocols/resumable-upload#upload-checksum
 func ParseTUSHash(checksum string) (hashAlgo, hash string, err error) {
@@ -47,6 +61,17 @@ func ParseTUSHash(checksum string) (hashAlgo, hash string, err error) {
 	return
 }
 
+// GenerateTUSConcatFinalHeader generates the `Concat` header value https://tus.io/protocols/resumable-upload#upload-concat
+func GenerateTUSConcatFinalHeader(partials []*url.URL) (header string, err error) {
+	header = fmt.Sprintf("final;%v", strings.Join(collection.Map[*url.URL, string](partials, func(u *url.URL) string {
+		if u == nil {
+			return ""
+		}
+		return u.EscapedPath()
+	}), " "))
+	return
+}
+
 // ParseTUSConcatHeader parses the `Concat` header value https://tus.io/protocols/resumable-upload#upload-concat
 func ParseTUSConcatHeader(concat string) (isPartial bool, partials []*url.URL, err error) {
 	header := strings.TrimSpace(concat)
@@ -73,6 +98,24 @@ func ParseTUSConcatHeader(concat string) (isPartial bool, partials []*url.URL, e
 	return
 }
 
+// GenerateTUSMetadataHeader generates the `metadata` header value https://tus.io/protocols/resumable-upload#upload-metadata
+func GenerateTUSMetadataHeader(filename *string, elements map[string]any) (header string, err error) {
+	newMap := make(map[string]string, len(elements))
+	for key, value := range elements {
+		valueB, ok := value.(bool)
+		if ok && valueB {
+			newMap[key] = ""
+		} else {
+			newMap[key] = base64.EncodeString(fmt.Sprintf("%v", value))
+		}
+	}
+	if !reflection.IsEmpty(filename) {
+		newMap[KeyTUSMetadata] = base64.EncodeString(field.OptionalString(filename, ""))
+	}
+	header = strings.Join(collection.ConvertMapToPairSlice(newMap, " "), ",")
+	return
+}
+
 // ParseTUSMetadataHeader parses the `metadata` header value https://tus.io/protocols/resumable-upload#upload-metadata
 func ParseTUSMetadataHeader(header string) (filename *string, elements map[string]any, err error) {
 	h := strings.TrimSpace(header)

utils/http/headers/tus/tus_test.go

@@ -77,6 +77,15 @@ func TestParseTUSHash(t *testing.T) {
 			expectedAlgo:     hashing.HashSha256,
 			expectedChecksum: "this is a test value obviously",
 		},
+		{
+			header: func() string {
+				header, err := GenerateTUSChecksumHeader(hashing.HashSha256, "the cloudy crew: josh jennings, kem govender, bianca bunaciu, adrien cabarbaye, abdelrahman abdelraouf, phuong linh nguyen")
+				require.NoError(t, err)
+				return header
+			}(),
+			expectedAlgo:     hashing.HashSha256,
+			expectedChecksum: "the cloudy crew: josh jennings, kem govender, bianca bunaciu, adrien cabarbaye, abdelrahman abdelraouf, phuong linh nguyen",
+		},
 		{
 			header:           "sha1-md5 Lve95gjOVATpfV8EL5X4nxwjKHE=",
 			expectedAlgo:     "sha1-md5",
@@ -146,6 +155,31 @@ func TestParseTUSConcatHeader(t *testing.T) {
 				"/y",
 			},
 		},
+		{
+			input: func() string {
+				header, err := GenerateTUSConcatFinalHeader(
+					[]*url.URL{
+						func() *url.URL {
+							u, err := url.Parse("/x")
+							require.NoError(t, err)
+							return u
+						}(),
+						func() *url.URL {
+							u, err := url.Parse("/ywh/h")
+							require.NoError(t, err)
+							return u
+						}(),
+					},
+				)
+				require.NoError(t, err)
+				return header
+			}(),
+			isPartial: false,
+			expectedPartialURL: []string{
+				"/x",
+				"/ywh/h",
+			},
+		},
 		{
 			input:     fmt.Sprintf("   final;   %v %v   ", url1, url2),
 			isPartial: false,
@@ -276,6 +310,25 @@ func TestParseTUSMetadataHeader(t *testing.T) {
 				"empty":    true,
 			},
 		},
+		{
+			input: func() string {
+				header, err := GenerateTUSMetadataHeader(field.ToOptionalString("test.txt"), map[string]any{
+					"meta":  "y",
+					"test":  false,
+					"empty": true,
+				},
+				)
+				require.NoError(t, err)
+				return header
+			}(),
+			expectedFilename: field.ToOptionalString("test.txt"),
+			expectedElements: map[string]any{
+				"filename": "test.txt",
+				"meta":     "y",
+				"test":     "false",
+				"empty":    true,
+			},
+		},
 		{
 			input: "note " + toBase64Encoded("A/B+C=D=="),
 			expectedElements: map[string]any{