Added IronCache (not used yet).

Using copy of reverse proxy so can get error response.

src/router/reverser.go

@@ -1,4 +1,9 @@
-// I wanted to do some stuff to this so had to make a copy. Namely change the Host handling for virtual hosts.
+/* I wanted to do some stuff to this so had to make a copy. Namely:
+- change the Host handling for virtual hosts.
+- get errors if the proxy request fails
+
+
+*/
 
 // Copyright 2011 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
@@ -83,7 +88,7 @@ func copyHeader(dst, src http.Header) {
 	}
 }
 
-func (p *ReverseProxy) ServeHTTP(rw http.ResponseWriter, req *http.Request) {
+func (p *ReverseProxy) ServeHTTP(rw http.ResponseWriter, req *http.Request) error {
 	transport := p.Transport
 	if transport == nil {
 		transport = http.DefaultTransport
@@ -115,8 +120,8 @@ func (p *ReverseProxy) ServeHTTP(rw http.ResponseWriter, req *http.Request) {
 	res, err := transport.RoundTrip(outreq)
 	if err != nil {
 		log.Printf("http: proxy error: %v", err)
-		rw.WriteHeader(http.StatusInternalServerError)
-		return
+		//		rw.WriteHeader(http.StatusInternalServerError)
+		return err
 	}
 	defer res.Body.Close()
 
@@ -124,6 +129,9 @@ func (p *ReverseProxy) ServeHTTP(rw http.ResponseWriter, req *http.Request) {
 
 	rw.WriteHeader(res.StatusCode)
 	p.copyResponse(rw, res.Body)
+
+	return nil
+
 }
 
 func (p *ReverseProxy) copyResponse(dst io.Writer, src io.Reader) {

src/router/router.go

@@ -11,19 +11,28 @@ import (
 	"encoding/json"
 	"fmt"
 	"github.com/gorilla/mux"
+	"github.com/iron-io/iron_go/cache"
+	// "github.com/iron-io/iron_go/config"
 	"log"
 	"math/rand"
 	"net/http"
-	"net/http/httputil"
 	"net/url"
 	"strings"
 )
 
 var routingTable = map[string]Route{}
+var icache = cache.New("routertest")
+
+func init() {
+	icache.Settings.UseConfigMap(map[string]interface{}{"token": "MWx0VfngzsCu0W8NAYw7S2lNrgo", "project_id": "50e227be8e7d14359b001373"})
+}
 
 type Route struct {
 	// TODO: Change destinations to a simple cache so it can expire entries after 55 minutes (the one we use in common?)
 	Destinations []string
+	ProjectId    string
+	Token        string // store this so we can queue up new workers on demand
+
 }
 
 // for adding new hosts
@@ -52,6 +61,11 @@ func main() {
 func ProxyFunc(w http.ResponseWriter, req *http.Request) {
 	fmt.Println("HOST:", req.Host)
 	host := strings.Split(req.Host, ":")[0]
+
+	// We look up the destinations in the routing table and there can be 3 possible scenarios:
+	// 1) This host was never registered so we return 404
+	// 2) This host has active workers so we do the proxy
+	// 3) This host has no active workers so we queue one (or more) up and return a 503 or something with message that says "try again in a minute"
 	route := routingTable[host]
 	// choose random dest
 	if len(route.Destinations) == 0 {
@@ -67,14 +81,28 @@ func ProxyFunc(w http.ResponseWriter, req *http.Request) {
 		panic(err)
 	}
 	fmt.Println("proxying to", destUrl)
-	proxy := httputil.NewSingleHostReverseProxy(destUrl)
-	proxy.ServeHTTP(w, req)
+	proxy := NewSingleHostReverseProxy(destUrl)
+	err = proxy.ServeHTTP(w, req)
+	if err != nil {
+		fmt.Println("Error proxying!", err)
+		w.WriteHeader(http.StatusInternalServerError)
+		// start new worker if it's a connection error
+		return
+	}
+	fmt.Println("Served!")
 	// todo: how to handle destination failures. I got this in log output when testing a bad endpoint:
 	// 2012/12/26 23:22:08 http: proxy error: dial tcp 127.0.0.1:8082: connection refused
 }
 
+// When a worker starts up, it calls this
 func AddWorker(w http.ResponseWriter, req *http.Request) {
 	log.Println("AddWorker called!")
+
+	// get project id and token
+	projectId := req.FormValue("project_id")
+	token := req.FormValue("token")
+	fmt.Println("project_id:", projectId, "token:", token)
+
 	r2 := Route2{}
 	decoder := json.NewDecoder(req.Body)
 	decoder.Decode(&r2)
@@ -82,9 +110,12 @@ func AddWorker(w http.ResponseWriter, req *http.Request) {
 	fmt.Println("DECODED:", r2)
 
 	// todo: routing table should be in mongo (or IronCache?) so all routers can update/read from it.
+	// todo: one cache entry per host domain
 	route := routingTable[r2.Host]
 	fmt.Println("ROUTE:", route)
 	route.Destinations = append(route.Destinations, r2.Dest)
+	route.ProjectId = projectId
+	route.Token = token
 	fmt.Println("ROUTE:", route)
 	routingTable[r2.Host] = route
 	fmt.Println("New routing table:", routingTable)

worker.rb

@@ -1,6 +1,8 @@
 require 'rest'
 require 'sinatra'
 
+# The backend would do this part before execute the worker
+########################################################
 rest = Rest::Client.new
 rest.logger.level = Logger::DEBUG
 
@@ -10,10 +12,9 @@ puts "public dns name: #{public_dns}"
 port = rand(50000..55000)
 puts "port: #{port}"
 
-
 response = rest.post(
 # "http://localhost:8080/",
-    "http://router.irondns.info/",
+    "http://router.irondns.info/?project_id=#{params[:project_id]}&token=#{params[:token]}",
 	headers: {"Iron-Router"=>"YES!"},
 	body: {"host"=>"routertest.irondns.info", "dest"=>"#{public_dns}:#{port}"})
 puts "body:"
@@ -21,6 +22,9 @@ puts response.body
 
 STDOUT.flush
 
+# Now we start the actual worker
+##################################################################3
+
 ENV['PORT'] = port.to_s # for sinatra
 my_app = Sinatra.new do
     set :port, port