Merge pull request #387 from hearchco/as/fix/ua

fix(useragent): better generation, with a fix

src/search/useragent/useragent.go

@@ -1,54 +1,63 @@
 package useragent
 
 import (
+	"fmt"
 	"math/rand"
+	"slices"
 	"time"
+
+	"github.com/rs/zerolog/log"
 )
 
+var browsers = [...]string{"chrome", "edge"}
+var versions = [...]int{127, 128}
+
 type userAgentWithHeaders struct {
 	UserAgent       string
 	SecCHUA         string
 	SecCHUAMobile   string
 	SecCHUAPlatform string
 }
 
-// UserAgents used when making requests and their corresponding Sec-Ch-Ua headers.
-var userAgentArray = [...]userAgentWithHeaders{
-	// Chrome 127.0.0, Mac OS X
-	{
-		"Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/127.0.0.0 Safari/537.3",
-		`"Google Chrome";v="127", "Chromium";v="127", "Not=A?Brand";v="24"`,
-		"?0",
-		`"Macintosh"`,
-	},
-	// Chrome 128.0.0, Windows
-	{
-		"Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/128.0.0.0 Safari/537.3",
-		`"Google Chrome";v="128", "Chromium";v="128", "Not=A?Brand";v="24"`,
-		"?0",
-		`"Windows"`,
-	},
-	// Chrome 127.0.0, Windows
-	{
-		"Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/127.0.0.0 Safari/537.3",
-		`"Google Chrome";v="127", "Chromium";v="127", "Not=A?Brand";v="24"`,
-		"?0",
-		`"Windows"`,
-	},
-	// Edge 128.0.0, Windows
-	{
-		"Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/128.0.0.0 Safari/537.36 Edg/128.0.0.",
-		`"Microsoft Edge";v="128", "Edg";v="128"`,
+func userAgentStruct(browser string, version int) userAgentWithHeaders {
+	if !slices.Contains(browsers[:], browser) {
+		log.Panic().
+			Str("browser", browser).
+			Msg("Invalid browser")
+		// ^PANIC - This should never happen
+	}
+	if !slices.Contains(versions[:], version) {
+		log.Panic().
+			Int("version", version).
+			Msg("Invalid version")
+		// ^PANIC - This should never happen
+	}
+
+	const userAgentTemplate = "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/%d.0.0.0 Safari/537.36"
+	userAgent := fmt.Sprintf(userAgentTemplate, version)
+	if browser == "edge" {
+		userAgent = fmt.Sprintf("%s Edg/%d.0.0.0", userAgent, version)
+	}
+
+	const secCHUATemplate = `"Chromium";v="%d", "Not;A=Brand";v="24", "%s";v="%d"`
+	secCHUA := fmt.Sprintf(secCHUATemplate, version, "Google Chrome", version)
+	if browser == "edge" {
+		secCHUA = fmt.Sprintf(secCHUATemplate, version, "Microsoft Edge", version)
+	}
+
+	return userAgentWithHeaders{
+		userAgent,
+		secCHUA,
 		"?0",
 		`"Windows"`,
-	},
+	}
 }
 
 func randomUserAgentStruct() userAgentWithHeaders {
 	// WARNING: Will stop working after year 2262.
 	randSrc := rand.NewSource(time.Now().UnixNano())
 	randGen := rand.New(randSrc)
-	return userAgentArray[randGen.Intn(len(userAgentArray))]
+	return userAgentStruct(browsers[randGen.Intn(len(browsers))], versions[randGen.Intn(len(versions))])
 }
 
 func RandomUserAgent() string {