pathway/pathway.go

package pathway

import (
	"io"
	"log"
	"net/http"
	"strings"
	"sync"
	// "nhooyr.io/websocket"
)

var (
	// actual business end of the device
	paths     *sync.Map
	debugging string
)

func init() {
	paths = &sync.Map{}
}

// Transfer holds a single tranferable connection to be read
type Transfer struct {
	reader        io.ReadCloser
	done          chan struct{}
	contentlength string
}

// NewTransfer returns a ready to use Transfer and it's writer
func NewTransfer(contentlength string) (transfer Transfer, writer io.WriteCloser) {
	var reader io.ReadCloser
	reader, writer = io.Pipe()

	transfer = Transfer{
		reader:        reader.(io.ReadCloser),
		contentlength: contentlength,
		done:          make(chan struct{}),
	}

	return
}

// Queue is where posts and gets can exchange transfers
type Queue struct {
	ch    chan Transfer
	posts int32
	gets  int32
}

func PathHandler(w http.ResponseWriter, r *http.Request) {
	pathID := r.URL.Path

	if len(pathID) < 2 {
		w.WriteHeader(400)
		w.Write([]byte("path to short"))
		return
	}

	if h := r.Header.Get("Connection"); len(h) > 0 && strings.ToLower(h) == "upgrade" {
		if h = r.Header.Get("Upgrade"); len(h) > 0 && strings.ToLower(h) == "websocket" {
			// c, err := websocket.Accept(w, r, nil)
			// if err != nil {
			// 	info("Websocket not accepted: %+s", err.Error())
			// 	return
			// }
			//
			// defer c.Close(websocket.StatusInternalError, "the sky is falling")
			info("Websocket connections not supported yet. Headers: %+v", r.Header)
			// return
		}
	}

	if r.Method == "GET" {
		info("%s [GET] Connected", pathID)
		handleGet(pathID, w, r)
	} else if r.Method == "POST" {
		info("%s [POST] Connected", pathID)
		if h := r.Header.Get("X-Pathway"); h == "pubsub" {
			debug("%s [PUBSUB] Upgrade POST to PUBSUB", pathID)
			handlePubSub(pathID, r)
		} else {
			handlePost(pathID, r)
		}
	} else {
		info("Unhandled request type: '%s'", r.Method)
	}
}

func info(msg string, args ...interface{}) {
	log.Printf("INFO | "+msg, args...)
}

func debug(msg string, args ...interface{}) {
	if len(debugging) > 0 {
		log.Printf("DEBUG | "+msg, args...)
	}
}