begin refactor of proxy engine

proxychain/rqm/masquerade_as_trusted_bot.go

@@ -0,0 +1,32 @@
+package rqm // ReQuestModifier
+
+import (
+	"ladder/proxychain"
+)
+
+// MasqueradeAsGoogleBot modifies user agent and x-forwarded for
+// to appear to be a Google Bot
+func MasqueradeAsGoogleBot() proxychain.RequestModification {
+	const botUA string = "Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; Googlebot/2.1; http://www.google.com/bot.html) Chrome/79.0.3945.120 Safari/537.36"
+	const botIP string = "66.249.78.8" // TODO: create a random ip pool from https://developers.google.com/static/search/apis/ipranges/googlebot.json
+	return masqueradeAsTrustedBot(botUA, botIP)
+}
+
+// MasqueradeAsBingBot modifies user agent and x-forwarded for
+// to appear to be a Bing Bot
+func MasqueradeAsBingBot() proxychain.RequestModification {
+	const botUA string = "Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; bingbot/2.0; +http://www.bing.com/bingbot.htm) Chrome/79.0.3945.120 Safari/537.36"
+	const botIP string = "13.66.144.9" // https://www.bing.com/toolbox/bingbot.json
+	return masqueradeAsTrustedBot(botUA, botIP)
+}
+
+func masqueradeAsTrustedBot(botUA string, botIP string) proxychain.RequestModification {
+	return func(px *proxychain.ProxyChain) error {
+		px.AddRequestModifications(
+			SpoofUserAgent(botUA),
+			SpoofXForwardedFor(botIP),
+			SpoofReferrer(""),
+		)
+		return nil
+	}
+}