feat: add mime to httpx

httpx/doc.go

@@ -0,0 +1,2 @@
+// Package httpx provides a set of utilities for working with the net/http package.
+package httpx

httpx/mime.go

@@ -0,0 +1,48 @@
+package httpx
+
+import (
+	"errors"
+	"io"
+	"mime"
+	"net/http"
+	"path/filepath"
+
+	"github.com/zeiss/pkg/utilx"
+)
+
+// GetContentTypeByExtension returns the content type of a file based on its extension.
+func GetContentTypeByExtension(file string) string {
+	ext := filepath.Ext(file)
+	switch ext {
+	case ".htm", ".html":
+		return "text/html"
+	case ".css":
+		return "text/css"
+	case ".js":
+		return "application/javascript"
+	default:
+		return mime.TypeByExtension(ext)
+	}
+}
+
+// GetContentType returns the content type of a file based on its extension.
+func GetContentType(seeker io.ReadSeeker) (string, error) {
+	// At most the first 512 bytes of data are used:
+	// https://golang.org/src/net/http/sniff.go?s=646:688#L11
+	buff := make([]byte, 512)
+
+	_, err := seeker.Seek(0, io.SeekStart)
+	if err != nil {
+		return "", err
+	}
+
+	bytesRead, err := seeker.Read(buff)
+	if utilx.NotEmpty(err) && !errors.Is(err, io.EOF) {
+		return "", err
+	}
+
+	// Slice to remove fill-up zero values which cause a wrong content type detection in the next step
+	buff = buff[:bytesRead]
+
+	return http.DetectContentType(buff), nil
+}

httpx/mime_test.go

@@ -0,0 +1,42 @@
+package httpx
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestGetContentTypeByExtension(t *testing.T) {
+	tests := []struct {
+		name     string
+		file     string
+		expected string
+	}{
+		{
+			name:     "html",
+			file:     "index.html",
+			expected: "text/html",
+		},
+		{
+			name:     "css",
+			file:     "style.css",
+			expected: "text/css",
+		},
+		{
+			name:     "js",
+			file:     "script.js",
+			expected: "application/javascript",
+		},
+		{
+			name:     "unknown",
+			file:     "file",
+			expected: "",
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			assert.Equal(t, test.expected, GetContentTypeByExtension(test.file))
+		})
+	}
+}