Restructured to have subpackages, added server communication

server/server.go

@@ -0,0 +1,106 @@
+package main
+
+import (
+	"asink"
+	"encoding/json"
+	"flag"
+	"fmt"
+	"io/ioutil"
+	"net/http"
+	"regexp"
+	"strconv"
+)
+
+var eventsRegexp *regexp.Regexp
+
+var port int = 8080
+func init() {
+	const port_usage = "Port on which to serve HTTP API"
+
+	flag.IntVar(&port, "port", 8080, port_usage)
+	flag.IntVar(&port, "p", 8080, port_usage+" (shorthand)")
+
+	eventsRegexp = regexp.MustCompile("^/events/([0-9]+)$")
+}
+
+func main() {
+	flag.Parse()
+
+	http.HandleFunc("/", rootHandler)
+	http.HandleFunc("/events", eventHandler)
+	http.HandleFunc("/events/", eventHandler)
+
+	//TODO replace with http://golang.org/pkg/net/http/#ListenAndServeTLS
+	err := http.ListenAndServe(fmt.Sprintf(":%d", port), nil)
+	if err != nil {
+		fmt.Println(err)
+	}
+}
+
+func rootHandler(w http.ResponseWriter, r *http.Request) {
+	fmt.Fprintf(w, "You're probably looking for /events/")
+}
+
+func getEvents(w http.ResponseWriter, r *http.Request, nextEvent uint64) {
+	fmt.Fprintf(w, strconv.FormatUint(nextEvent, 10))
+}
+
+func putEvents(w http.ResponseWriter, r *http.Request) {
+	var events asink.EventList
+	var error_occurred bool = false
+	var error_message string = ""
+	defer func() {
+		var apiresponse asink.APIResponse
+		if error_occurred {
+			apiresponse = asink.APIResponse{
+				Status: "error",
+				Explanation: error_message,
+			}
+		} else {
+			apiresponse = asink.APIResponse{
+				Status: "success",
+			}
+		}
+		b, err := json.Marshal(apiresponse)
+		if err != nil {
+			panic(err)
+		}
+		w.Write(b)
+	}()
+
+	body, err := ioutil.ReadAll(r.Body)
+	if err != nil {
+		error_message = err.Error()
+		return
+	}
+	err = json.Unmarshal(body, &events)
+	if err != nil {
+		error_message = err.Error()
+		return
+	}
+	for _, event := range events.Events {
+		fmt.Println(event)
+	}
+}
+
+func eventHandler(w http.ResponseWriter, r *http.Request) {
+	if r.Method == "GET" {
+		//if GET, return any events later than (and including) the event id passed in
+		if sm := eventsRegexp.FindStringSubmatch(r.RequestURI); sm != nil {
+			i, err := strconv.ParseUint(sm[1], 10, 64)
+			if err != nil {
+				//TODO display error message here instead
+				fmt.Printf("ERROR parsing " + sm[1] + "\n")
+				getEvents(w, r, 0)
+			} else {
+				getEvents(w, r, i)
+			}
+		} else {
+			getEvents(w, r, 0)
+		}
+	} else if r.Method == "POST" {
+		putEvents(w, r)
+	} else {
+		fmt.Fprintf(w, "You f-ed up.")
+	}
+}