internalize format helpers (#2543)

Signed-off-by: Alex Goodman <wagoodman@users.noreply.github.com>

internal/mimetype/mimetype_helper.go

@@ -0,0 +1,73 @@
+package mimetype
+
+import "github.com/scylladb/go-set/strset"
+
+var (
+	ArchiveMIMETypeSet = strset.New(
+		// derived from https://en.wikipedia.org/wiki/List_of_archive_formats
+		[]string{
+			// archive only
+			"application/x-archive",
+			"application/x-cpio",
+			"application/x-shar",
+			"application/x-iso9660-image",
+			"application/x-sbx",
+			"application/x-tar",
+			// compression only
+			"application/x-bzip2",
+			"application/gzip",
+			"application/x-lzip",
+			"application/x-lzma",
+			"application/x-lzop",
+			"application/x-snappy-framed",
+			"application/x-xz",
+			"application/x-compress",
+			"application/zstd",
+			// archiving and compression
+			"application/x-7z-compressed",
+			"application/x-ace-compressed",
+			"application/x-astrotite-afa",
+			"application/x-alz-compressed",
+			"application/vnd.android.package-archive",
+			"application/x-freearc",
+			"application/x-arj",
+			"application/x-b1",
+			"application/vnd.ms-cab-compressed",
+			"application/x-cfs-compressed",
+			"application/x-dar",
+			"application/x-dgc-compressed",
+			"application/x-apple-diskimage",
+			"application/x-gca-compressed",
+			"application/java-archive",
+			"application/x-lzh",
+			"application/x-lzx",
+			"application/x-rar-compressed",
+			"application/x-stuffit",
+			"application/x-stuffitx",
+			"application/x-gtar",
+			"application/x-ms-wim",
+			"application/x-xar",
+			"application/zip",
+			"application/x-zoo",
+		}...,
+	)
+
+	ExecutableMIMETypeSet = strset.New(
+		[]string{
+			"application/x-executable",
+			"application/x-mach-binary",
+			"application/x-elf",
+			"application/x-sharedlib",
+			"application/vnd.microsoft.portable-executable",
+			"application/x-executable",
+		}...,
+	)
+)
+
+func IsArchive(mimeType string) bool {
+	return ArchiveMIMETypeSet.Has(mimeType)
+}
+
+func IsExecutable(mimeType string) bool {
+	return ExecutableMIMETypeSet.Has(mimeType)
+}

internal/mimetype/mimetype_helper_test.go

@@ -0,0 +1,57 @@
+package mimetype
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func Test_IsArchive(t *testing.T) {
+
+	tests := []struct {
+		name     string
+		mimeType string
+		expected bool
+	}{
+		{
+			name:     "not an archive",
+			mimeType: "application/vnd.unknown",
+			expected: false,
+		},
+		{
+			name:     "archive",
+			mimeType: "application/x-rar-compressed",
+			expected: true,
+		},
+	}
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			assert.Equal(t, test.expected, IsArchive(test.mimeType))
+		})
+	}
+}
+
+func Test_IsExecutable(t *testing.T) {
+
+	tests := []struct {
+		name     string
+		mimeType string
+		expected bool
+	}{
+		{
+			name:     "not an executable",
+			mimeType: "application/vnd.unknown",
+			expected: false,
+		},
+		{
+			name:     "executable",
+			mimeType: "application/x-mach-binary",
+			expected: true,
+		},
+	}
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			assert.Equal(t, test.expected, IsExecutable(test.mimeType))
+		})
+	}
+}