initial middleware refactor

tracker/tracker.go

@@ -0,0 +1,64 @@
+// Copyright 2016 The Chihaya Authors. All rights reserved.
+// Use of this source code is governed by the BSD 2-Clause license,
+// which can be found in the LICENSE file.package middleware
+
+package tracker
+
+import (
+	"errors"
+
+	"github.com/chihaya/chihaya"
+	"github.com/chihaya/chihaya/config"
+)
+
+// Tracker represents a protocol independent, middleware-composed BitTorrent
+// tracker.
+type Tracker struct {
+	cfg            *config.TrackerConfig
+	handleAnnounce AnnounceHandler
+	handleScrape   ScrapeHandler
+}
+
+// NewTracker parses a config and generates a Tracker composed by the middleware
+// specified in the config.
+func NewTracker(cfg *config.TrackerConfig) (*Tracker, error) {
+	var achain announceChain
+	for _, mwName := range cfg.AnnounceMiddleware {
+		mw, ok := announceMiddleware[mwName]
+		if !ok {
+			return nil, errors.New("failed to find announce middleware: " + mwName)
+		}
+		achain.Append(mw)
+	}
+
+	var schain scrapeChain
+	for _, mwName := range cfg.ScrapeMiddleware {
+		mw, ok := scrapeMiddleware[mwName]
+		if !ok {
+			return nil, errors.New("failed to find scrape middleware: " + mwName)
+		}
+		schain.Append(mw)
+	}
+
+	return &Tracker{
+		cfg:            cfg,
+		handleAnnounce: achain.Handler(),
+		handleScrape:   schain.Handler(),
+	}, nil
+}
+
+// HandleAnnounce runs an AnnounceRequest through a Tracker's middleware and
+// returns the result.
+func (t *Tracker) HandleAnnounce(req chihaya.AnnounceRequest) (*chihaya.AnnounceResponse, error) {
+	resp := &chihaya.AnnounceResponse{}
+	err := t.handleAnnounce(t.cfg, req, resp)
+	return resp, err
+}
+
+// HandleScrape runs a ScrapeRequest through a Tracker's middleware and returns
+// the result.
+func (t *Tracker) HandleScrape(req chihaya.ScrapeRequest) (*chihaya.ScrapeResponse, error) {
+	resp := &chihaya.ScrapeResponse{}
+	err := t.handleScrape(t.cfg, req, resp)
+	return resp, err
+}