Clock matcher (#225)

* Clock matcher: initial commit

* Clock matcher: add time zone support

* Clock matcher: use UTC by default

* Clock matcher: add custom offset support

* Clock matcher: provide comments for fields

README.md

@@ -30,6 +30,7 @@ This app works similarly to the `http` app. You define servers, and each server
 
 Current matchers:
 
+- **layer4.matchers.clock** - matches connections on the time they are wrapped/matched.
 - **layer4.matchers.http** - matches connections that start with HTTP requests. In addition, any [`http.matchers` modules](https://caddyserver.com/docs/modules/) can be used for matching on HTTP-specific properties of requests, such as header or path. Note that only the first request of each connection can be used for matching.
 - **layer4.matchers.tls** - matches connections that start with TLS handshakes. In addition, any [`tls.handshake_match` modules](https://caddyserver.com/docs/modules/) can be used for matching on TLS-specific properties of the ClientHello, such as ServerName (SNI).
 - **layer4.matchers.ssh** - matches connections that look like SSH connections.

imports.go

@@ -17,6 +17,7 @@ package caddyl4
 import (
 	// plugging in the standard modules for the layer4 app
 	_ "github.com/mholt/caddy-l4/layer4"
+	_ "github.com/mholt/caddy-l4/modules/l4clock"
 	_ "github.com/mholt/caddy-l4/modules/l4echo"
 	_ "github.com/mholt/caddy-l4/modules/l4http"
 	_ "github.com/mholt/caddy-l4/modules/l4postgres"

integration/caddyfile_adapt/gd_matcher_clock.caddytest

@@ -0,0 +1,220 @@
+{
+	layer4 {
+		:8080 {
+			@night_m clock before 05:00:00
+			@morning clock 05:00:00 12:00:00
+			@afternoon clock 12:00:00 17:00:00
+			@evening clock 17:00:00 21:00:00
+			@night_e clock after 21:00:00
+			route @night_m @night_e {
+				proxy 00.upstream.local:8080
+			}
+			route @morning {
+				proxy 01.upstream.local:8080 02.upstream.local:8080
+			}
+			route @afternoon {
+				proxy 03.upstream.local:8080 04.upstream.local:8080 05.upstream.local:8080
+			}
+			route @evening {
+				proxy 06.upstream.local:8080 07.upstream.local:8080
+			}
+		}
+		:8888 {
+			@la_is_awake clock 08:00:00 20:00:00 America/Los_Angeles
+			route @la_is_awake {
+				proxy existing.machine.local:8888
+			}
+			@la_is_asleep not clock 08:00:00 20:00:00 America/Los_Angeles
+			route @la_is_asleep {
+				proxy non-existing.machine.local:8888
+			}
+		}
+	}
+}
+----------
+{
+	"apps": {
+		"layer4": {
+			"servers": {
+				"srv0": {
+					"listen": [
+						":8080"
+					],
+					"routes": [
+						{
+							"match": [
+								{
+									"clock": {
+										"after": "00:00:00",
+										"before": "05:00:00"
+									}
+								},
+								{
+									"clock": {
+										"after": "21:00:00",
+										"before": "00:00:00"
+									}
+								}
+							],
+							"handle": [
+								{
+									"handler": "proxy",
+									"upstreams": [
+										{
+											"dial": [
+												"00.upstream.local:8080"
+											]
+										}
+									]
+								}
+							]
+						},
+						{
+							"match": [
+								{
+									"clock": {
+										"after": "05:00:00",
+										"before": "12:00:00"
+									}
+								}
+							],
+							"handle": [
+								{
+									"handler": "proxy",
+									"upstreams": [
+										{
+											"dial": [
+												"01.upstream.local:8080"
+											]
+										},
+										{
+											"dial": [
+												"02.upstream.local:8080"
+											]
+										}
+									]
+								}
+							]
+						},
+						{
+							"match": [
+								{
+									"clock": {
+										"after": "12:00:00",
+										"before": "17:00:00"
+									}
+								}
+							],
+							"handle": [
+								{
+									"handler": "proxy",
+									"upstreams": [
+										{
+											"dial": [
+												"03.upstream.local:8080"
+											]
+										},
+										{
+											"dial": [
+												"04.upstream.local:8080"
+											]
+										},
+										{
+											"dial": [
+												"05.upstream.local:8080"
+											]
+										}
+									]
+								}
+							]
+						},
+						{
+							"match": [
+								{
+									"clock": {
+										"after": "17:00:00",
+										"before": "21:00:00"
+									}
+								}
+							],
+							"handle": [
+								{
+									"handler": "proxy",
+									"upstreams": [
+										{
+											"dial": [
+												"06.upstream.local:8080"
+											]
+										},
+										{
+											"dial": [
+												"07.upstream.local:8080"
+											]
+										}
+									]
+								}
+							]
+						}
+					]
+				},
+				"srv1": {
+					"listen": [
+						":8888"
+					],
+					"routes": [
+						{
+							"match": [
+								{
+									"clock": {
+										"after": "08:00:00",
+										"before": "20:00:00",
+										"timezone": "America/Los_Angeles"
+									}
+								}
+							],
+							"handle": [
+								{
+									"handler": "proxy",
+									"upstreams": [
+										{
+											"dial": [
+												"existing.machine.local:8888"
+											]
+										}
+									]
+								}
+							]
+						},
+						{
+							"match": [
+								{
+									"not": [
+										{
+											"clock": {
+												"after": "08:00:00",
+												"before": "20:00:00",
+												"timezone": "America/Los_Angeles"
+											}
+										}
+									]
+								}
+							],
+							"handle": [
+								{
+									"handler": "proxy",
+									"upstreams": [
+										{
+											"dial": [
+												"non-existing.machine.local:8888"
+											]
+										}
+									]
+								}
+							]
+						}
+					]
+				}
+			}
+		}
+	}
+}

layer4/connection.go

@@ -19,6 +19,7 @@ import (
 	"errors"
 	"net"
 	"sync"
+	"time"
 
 	"github.com/caddyserver/caddy/v2"
 	"go.uber.org/zap"
@@ -33,6 +34,7 @@ func WrapConnection(underlying net.Conn, buf []byte, logger *zap.Logger) *Connec
 	repl := caddy.NewReplacer()
 	repl.Set("l4.conn.remote_addr", underlying.RemoteAddr())
 	repl.Set("l4.conn.local_addr", underlying.LocalAddr())
+	repl.Set("l4.conn.wrap_time", time.Now().UTC())
 
 	ctx := context.Background()
 	ctx = context.WithValue(ctx, VarsCtxKey, make(map[string]interface{}))