initial import

app/router/pathc.go

@@ -0,0 +1,71 @@
+package router
+
+import (
+	"fmt"
+	"strings"
+)
+
+const (
+	compContextPlain int = iota
+	compContextRegex
+
+	startRegex byte = '{'
+	stopRegex  byte = '}'
+)
+
+func pathCompiler(path string) (string, error) {
+	var err error
+	res := make([]byte, 0)
+	var pos int = compContextPlain
+	var depth int = 0
+	pattern := make([]byte, 0)
+	for _, b := range []byte(path) {
+		switch pos {
+		case compContextPlain:
+			switch b {
+			case stopRegex:
+				depth -= 1
+				res = append(res, b)
+			case startRegex:
+				depth += 1
+				pos = compContextRegex // pattern started
+				pattern = make([]byte, 0)
+			default:
+				res = append(res, b)
+			}
+		case compContextRegex:
+			switch b {
+			case startRegex:
+				depth += 1
+			case stopRegex:
+				depth -= 1
+				if depth == 0 {
+					pattern = convertRegexp(pattern)
+					res = append(res, pattern...)
+					pos = compContextPlain // pattern ended
+				}
+			default:
+				pattern = append(pattern, b)
+			}
+		}
+	}
+	if depth != 0 {
+		err = fmt.Errorf("Unbalanced brackets into pattern")
+	}
+	return string(res), err
+}
+
+const (
+	defaultRegexp = `[a-zA-Z0-9_][\-\.a-zA-Z0-9_%%=:~]+`
+)
+
+func convertRegexp(src []byte) []byte {
+	var res string
+	const patternSeps = ":"
+	parts := strings.SplitN(string(src), patternSeps, 2)
+	if len(parts) == 1 {
+		parts = append(parts, defaultRegexp)
+	}
+	res = fmt.Sprintf("(?<%s>%s)", parts[0], parts[1])
+	return []byte(res)
+}