feat: ease operation behind proxy servers (#974)

challenge/http01/domain_matcher_test.go

@@ -0,0 +1,86 @@
+package http01
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestParseForwardedHeader(t *testing.T) {
+	testCases := []struct {
+		name  string
+		input string
+		want  []map[string]string
+		err   string
+	}{
+		{
+			name:  "empty input",
+			input: "",
+			want:  nil,
+		},
+		{
+			name:  "simple case",
+			input: `for=1.2.3.4;host=example.com; by=127.0.0.1`,
+			want: []map[string]string{
+				{"for": "1.2.3.4", "host": "example.com", "by": "127.0.0.1"},
+			},
+		},
+		{
+			name:  "quoted-string",
+			input: `foo="bar"`,
+			want: []map[string]string{
+				{"foo": "bar"},
+			},
+		},
+		{
+			name:  "multiple entries",
+			input: `a=1, b=2; c=3, d=4`,
+			want: []map[string]string{
+				{"a": "1"},
+				{"b": "2", "c": "3"},
+				{"d": "4"},
+			},
+		},
+		{
+			name:  "whitespace",
+			input: "   a =  1,\tb\n=\r\n2,c=\"   untrimmed  \"",
+			want: []map[string]string{
+				{"a": "1"},
+				{"b": "2"},
+				{"c": "   untrimmed  "},
+			},
+		},
+		{
+			name:  "unterminated quote",
+			input: `x="y`,
+			err:   "unterminated quoted-string",
+		},
+		{
+			name:  "unexpected quote",
+			input: `"x=y"`,
+			err:   "unexpected quote",
+		},
+		{
+			name:  "invalid token",
+			input: `a=b, ipv6=[fe80::1], x=y`,
+			err:   "invalid token character at pos 10: [",
+		},
+	}
+
+	for _, test := range testCases {
+		test := test
+		t.Run(test.name, func(t *testing.T) {
+			t.Parallel()
+
+			actual, err := parseForwardedHeader(test.input)
+			if test.err == "" {
+				require.NoError(t, err)
+				assert.EqualValues(t, test.want, actual)
+			} else {
+				require.Error(t, err)
+				assert.Contains(t, err.Error(), test.err)
+			}
+		})
+	}
+}