From 9ad9d1805beccf87a67c0f801025337558a9b192 Mon Sep 17 00:00:00 2001
From: donutloop <marcel.edmund.franke@gmail.com>
Date: Sun, 26 Dec 2021 14:16:20 +0100
Subject: [PATCH] Regex validators: Precompile all known regex patterns (#3)

Reduce executions time of pattern matching, regex patterns are expensive to
compile at runtime.
---
 validator/validator.go | 59 +++++++++++++++++++++---------------------
 1 file changed, 30 insertions(+), 29 deletions(-)

diff --git a/validator/validator.go b/validator/validator.go
index c8b1da2..8b6128e 100644
--- a/validator/validator.go
+++ b/validator/validator.go
@@ -11,11 +11,11 @@ import (
 	"unicode"
 )
 
+var isAlphaRegexMatcher *regexp.Regexp = regexp.MustCompile(`^[a-zA-Z]+$`)
+
 // IsAlpha checks if the string contains only letters (a-zA-Z)
 func IsAlpha(s string) bool {
-	pattern := `^[a-zA-Z]+$`
-	reg := regexp.MustCompile(pattern)
-	return reg.MatchString(s)
+	return isAlphaRegexMatcher.MatchString(s)
 }
 
 // IsNumberStr check if the string can convert to a number.
@@ -29,10 +29,11 @@ func IsFloatStr(s string) bool {
 	return e == nil
 }
 
+var isIntStrRegexMatcher *regexp.Regexp = regexp.MustCompile(`^[\+-]?\d+$`)
+
 // IsIntStr check if the string can convert to a integer.
 func IsIntStr(s string) bool {
-	match, _ := regexp.MatchString(`^[\+-]?\d+$`, s)
-	return match
+	return isIntStrRegexMatcher.MatchString(s)
 }
 
 // IsIp check if the string is a ip address.
@@ -71,61 +72,61 @@ func IsIpV6(ipstr string) bool {
 	return false
 }
 
+var isDnsRegexMatcher *regexp.Regexp = regexp.MustCompile(`^[a-zA-Z]([a-zA-Z0-9\-]+[\.]?)*[a-zA-Z0-9]$`)
+
 // IsDns check if the string is dns.
 func IsDns(dns string) bool {
-	pattern := `^[a-zA-Z]([a-zA-Z0-9\-]+[\.]?)*[a-zA-Z0-9]$`
-	reg := regexp.MustCompile(pattern)
-	return reg.MatchString(dns)
+	return isDnsRegexMatcher.MatchString(dns)
 }
 
+var isEmailRegexMatcher *regexp.Regexp = regexp.MustCompile(`\w+([-+.]\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*`)
+
 // IsEmail check if the string is a email address.
 func IsEmail(email string) bool {
-	pattern := `\w+([-+.]\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*`
-	reg := regexp.MustCompile(pattern)
-	return reg.MatchString(email)
+	return isEmailRegexMatcher.MatchString(email)
 }
 
+var isChineseMobileRegexMatcher *regexp.Regexp = regexp.MustCompile("^((13[0-9])|(14[5,7])|(15[0-3,5-9])|(17[0,3,5-8])|(18[0-9])|166|198|199|(147))\\d{8}$")
+
 // IsChineseMobile check if the string is chinese mobile number.
 func IsChineseMobile(mobileNum string) bool {
-	pattern := "^((13[0-9])|(14[5,7])|(15[0-3,5-9])|(17[0,3,5-8])|(18[0-9])|166|198|199|(147))\\d{8}$"
-	reg := regexp.MustCompile(pattern)
-	return reg.MatchString(mobileNum)
+	return isChineseMobileRegexMatcher.MatchString(mobileNum)
 }
 
+var isChineseIdNumRegexMatcher *regexp.Regexp = regexp.MustCompile(`^[1-9]\d{5}(18|19|20|21|22)\d{2}((0[1-9])|(1[0-2]))(([0-2][1-9])|10|20|30|31)\d{3}[0-9Xx]$`)
+
 // IsChineseIdNum check if the string is chinese id number.
 func IsChineseIdNum(id string) bool {
-	pattern := `^[1-9]\d{5}(18|19|20|21|22)\d{2}((0[1-9])|(1[0-2]))(([0-2][1-9])|10|20|30|31)\d{3}[0-9Xx]$`
-	reg := regexp.MustCompile(pattern)
-	return reg.MatchString(id)
+	return isChineseIdNumRegexMatcher.MatchString(id)
 }
 
+var containChineseRegexMatcher *regexp.Regexp = regexp.MustCompile("[\u4e00-\u9fa5]")
+
 // ContainChinese check if the string contain mandarin chinese.
 func ContainChinese(s string) bool {
-	pattern := "[\u4e00-\u9fa5]"
-	reg := regexp.MustCompile(pattern)
-	return reg.MatchString(s)
+	return containChineseRegexMatcher.MatchString(s)
 }
 
+var isChinesePhoneRegexMatcher *regexp.Regexp = regexp.MustCompile(`\d{3}-\d{8}|\d{4}-\d{7}`)
+
 // IsChinesePhone check if the string is chinese phone number.
 // Valid chinese phone is xxx-xxxxxxxx or xxxx-xxxxxxx
 func IsChinesePhone(phone string) bool {
-	pattern := `\d{3}-\d{8}|\d{4}-\d{7}`
-	reg := regexp.MustCompile(pattern)
-	return reg.MatchString(phone)
+	return isChinesePhoneRegexMatcher.MatchString(phone)
 }
 
+var isCreditCardRegexMatcher *regexp.Regexp = regexp.MustCompile(`^(?:4[0-9]{12}(?:[0-9]{3})?|5[1-5][0-9]{14}|(222[1-9]|22[3-9][0-9]|2[3-6][0-9]{2}|27[01][0-9]|2720)[0-9]{12}|6(?:011|5[0-9][0-9])[0-9]{12}|3[47][0-9]{13}|3(?:0[0-5]|[68][0-9])[0-9]{11}|(?:2131|1800|35\\d{3})\\d{11}|6[27][0-9]{14})$`)
+
 // IsCreditCard check if the string is credit card.
 func IsCreditCard(creditCart string) bool {
-	pattern := `^(?:4[0-9]{12}(?:[0-9]{3})?|5[1-5][0-9]{14}|(222[1-9]|22[3-9][0-9]|2[3-6][0-9]{2}|27[01][0-9]|2720)[0-9]{12}|6(?:011|5[0-9][0-9])[0-9]{12}|3[47][0-9]{13}|3(?:0[0-5]|[68][0-9])[0-9]{11}|(?:2131|1800|35\\d{3})\\d{11}|6[27][0-9]{14})$`
-	reg := regexp.MustCompile(pattern)
-	return reg.MatchString(creditCart)
+	return isCreditCardRegexMatcher.MatchString(creditCart)
 }
 
+var isBase64RegexMatcher *regexp.Regexp = regexp.MustCompile(`^(?:[A-Za-z0-9+\\/]{4})*(?:[A-Za-z0-9+\\/]{2}==|[A-Za-z0-9+\\/]{3}=|[A-Za-z0-9+\\/]{4})$`)
+
 // IsBase64 check if the string is base64 string.
 func IsBase64(base64 string) bool {
-	pattern := `^(?:[A-Za-z0-9+\\/]{4})*(?:[A-Za-z0-9+\\/]{2}==|[A-Za-z0-9+\\/]{3}=|[A-Za-z0-9+\\/]{4})$`
-	reg := regexp.MustCompile(pattern)
-	return reg.MatchString(base64)
+	return isBase64RegexMatcher.MatchString(base64)
 }
 
 // IsEmptyString check if the string is empty.