1package sockjs
2
3import (
4	"fmt"
5	"net/http"
6	"time"
7)
8
9func xhrCorsFactory(opts Options) func(rw http.ResponseWriter, req *http.Request) {
10	return func(rw http.ResponseWriter, req *http.Request) {
11		header := rw.Header()
12		var corsEnabled bool
13		var corsOrigin string
14
15		if opts.CheckOrigin != nil {
16			corsEnabled = opts.CheckOrigin(req)
17			if corsEnabled {
18				corsOrigin = req.Header.Get("origin")
19				if corsOrigin == "" {
20					corsOrigin = "*"
21				}
22			}
23		} else {
24			corsEnabled = true
25			corsOrigin = opts.Origin
26			if corsOrigin == "" {
27				corsOrigin = req.Header.Get("origin")
28			}
29			if corsOrigin == "" || corsOrigin == "null" {
30				corsOrigin = "*"
31			}
32		}
33
34		if corsEnabled {
35			header.Set("Access-Control-Allow-Origin", corsOrigin)
36			if allowHeaders := req.Header.Get("Access-Control-Request-Headers"); allowHeaders != "" && allowHeaders != "null" {
37				header.Add("Access-Control-Allow-Headers", allowHeaders)
38			}
39			header.Set("Access-Control-Allow-Credentials", "true")
40		}
41	}
42}
43
44func xhrOptions(rw http.ResponseWriter, req *http.Request) {
45	rw.Header().Set("Access-Control-Allow-Methods", "OPTIONS, POST")
46	rw.WriteHeader(http.StatusNoContent) // 204
47}
48
49func cacheFor(rw http.ResponseWriter, req *http.Request) {
50	rw.Header().Set("Cache-Control", fmt.Sprintf("public, max-age=%d", 365*24*60*60))
51	rw.Header().Set("Expires", time.Now().AddDate(1, 0, 0).Format(time.RFC1123))
52	rw.Header().Set("Access-Control-Max-Age", fmt.Sprintf("%d", 365*24*60*60))
53}
54
55func noCache(rw http.ResponseWriter, req *http.Request) {
56	rw.Header().Set("Cache-Control", "no-store, no-cache, must-revalidate, max-age=0")
57}
58
59func welcomeHandler(rw http.ResponseWriter, req *http.Request) {
60	rw.Header().Set("content-type", "text/plain;charset=UTF-8")
61	fmt.Fprint(rw, "Welcome to SockJS!\n")
62}
63
64func httpError(w http.ResponseWriter, error string, code int) {
65	w.Header().Set("Content-Type", "text/plain; charset=utf-8")
66	w.WriteHeader(code)
67	fmt.Fprint(w, error)
68}
69