add doc for port range mapping (#4081)

README.md

@@ -78,6 +78,7 @@ frp also offers a P2P connect mode.
     * [URL Routing](#url-routing)
     * [TCP Port Multiplexing](#tcp-port-multiplexing)
     * [Connecting to frps via PROXY](#connecting-to-frps-via-proxy)
+    * [Port range mapping](#port-range-mapping)
     * [Client Plugins](#client-plugins)
     * [Server Manage Plugins](#server-manage-plugins)
     * [SSH Tunnel Gateway](#ssh-tunnel-gateway)
@@ -1158,6 +1159,24 @@ serverPort = 7000
 transport.proxyURL = "http://user:pwd@192.168.1.128:8080"
 ```
 
+### Port range mapping
+
+*Added in v0.56.0*
+
+We can use the range syntax of Go template combined with the built-in `parseNumberRangePair` function to achieve port range mapping.
+
+The following example, when run, will create 8 proxies named `test-6000, test-6001 ... test-6007`, each mapping the remote port to the local port.
+
+```
+{{- range $_, $v := parseNumberRangePair "6000-6006,6007" "6000-6006,6007" }}
+[[proxies]]
+name = "tcp-{{ $v.First }}"
+type = "tcp"
+localPort = {{ $v.First }}
+remotePort = {{ $v.Second }}
+{{- end }}
+```
+
 ### Client Plugins
 
 frpc only forwards requests to local TCP or UDP ports by default.

go.mod

@@ -5,7 +5,7 @@ go 1.22
 require (
 	github.com/armon/go-socks5 v0.0.0-20160902184237-e75332964ef5
 	github.com/coreos/go-oidc/v3 v3.6.0
-	github.com/fatedier/golib v0.4.1
+	github.com/fatedier/golib v0.4.2
 	github.com/google/uuid v1.3.0
 	github.com/gorilla/mux v1.8.0
 	github.com/gorilla/websocket v1.5.0

go.sum

@@ -24,8 +24,8 @@ github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSs
 github.com/envoyproxy/go-control-plane v0.9.0/go.mod h1:YTl/9mNaCwkRvm6d1a2C3ymFceY/DCBVvsKhRF0iEA4=
 github.com/envoyproxy/go-control-plane v0.9.4/go.mod h1:6rpuAdCZL397s3pYoYcLgu1mIlRU8Am5FuJP05cCM98=
 github.com/envoyproxy/protoc-gen-validate v0.1.0/go.mod h1:iSmxcyjqTsJpI2R4NaDN7+kN2VEUnK/pcBlmesArF7c=
-github.com/fatedier/golib v0.4.1 h1:C37VN3M+F3nUdh13laZsiyb5EXNe3tZnUdoHi+7rx+Q=
-github.com/fatedier/golib v0.4.1/go.mod h1:gpu+1vXxtJ072NYaNsn/YWgojDL8Ap2kFZQtbzT2qkg=
+github.com/fatedier/golib v0.4.2 h1:k+ZBdUFTTipnP1RHfEhGbzyShRdz/rZtFGnjpXG9D9c=
+github.com/fatedier/golib v0.4.2/go.mod h1:gpu+1vXxtJ072NYaNsn/YWgojDL8Ap2kFZQtbzT2qkg=
 github.com/fatedier/yamux v0.0.0-20230628132301-7aca4898904d h1:ynk1ra0RUqDWQfvFi5KtMiSobkVQ3cNc0ODb8CfIETo=
 github.com/fatedier/yamux v0.0.0-20230628132301-7aca4898904d/go.mod h1:CtWFDAQgb7dxtzFs4tWbplKIe2jSi3+5vKbgIO0SLnQ=
 github.com/go-jose/go-jose/v3 v3.0.1 h1:pWmKFVtt+Jl0vBZTIpz/eAKwsm6LkIxDVVbFHKkchhA=