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