Golang bitwrk.Logger类代码示例

func (a *BuyActivity) requestMissingChunks(log bitwrk.Logger, client *http.Client) (io.ReadCloser, error) {
	// Send chunk list of work to client
	pipeIn, pipeOut := io.Pipe()
	defer pipeIn.Close()
	mwriter := multipart.NewWriter(pipeOut)

	// Write chunk hashes into pipe for HTTP request
	go func() {
		defer pipeOut.Close()
		if err := a.encodeChunkedFirstTransmission(log, mwriter); err != nil {
			pipeOut.CloseWithError(err)
			return
		}
		if err := mwriter.Close(); err != nil {
			pipeOut.CloseWithError(err)
			return
		}
		log.Printf("Work chunk hashes transmitted successfully.")
	}()

	if r, err := a.postToSeller(pipeIn, mwriter.FormDataContentType(), false, client); err != nil {
		return nil, fmt.Errorf("Error sending work chunk hashes to seller: %v", err)
	} else {
		return r, nil
	}
}

func (a *BuyActivity) sendMissingChunksAndReturnResult(log bitwrk.Logger, client *http.Client, wishList []byte) (io.ReadCloser, error) {
	// Send data of missing chunks to seller
	pipeIn, pipeOut := io.Pipe()
	defer pipeIn.Close()
	mwriter := multipart.NewWriter(pipeOut)

	// Write work chunks into pipe for HTTP request
	go func() {
		defer pipeOut.Close()
		if part, err := mwriter.CreateFormFile("chunkdata", "chunkdata.bin"); err != nil {
			pipeOut.CloseWithError(err)
			return
		} else if err := cafs.WriteRequestedChunks(a.workFile, wishList, part); err != nil {
			pipeOut.CloseWithError(err)
			return
		}
		if err := mwriter.Close(); err != nil {
			pipeOut.CloseWithError(err)
			return
		}
		log.Printf("Missing chunk data transmitted successfully.")
	}()

	if r, err := a.postToSeller(pipeIn, mwriter.FormDataContentType(), client); err != nil {
		return nil, fmt.Errorf("Error sending work chunk data to seller: %v", err)
	} else {
		return r, nil
	}
}

func (t *Trade) updateTransaction(log bitwrk.Logger) error {
	attemptsLeft := 3
	for attemptsLeft > 0 {
		attemptsLeft--
		if tx, etag, err := FetchTx(t.txId, ""); err != nil {
			log.Printf("Error updating transaction: %v (attempts left: %d)", err, attemptsLeft)
			if attemptsLeft > 0 {
				time.Sleep(5 * time.Second)
			} else {
				return err
			}
		} else {
			expired := false
			func() {
				t.condition.L.Lock()
				defer t.condition.L.Unlock()
				if etag != t.txETag {
					t.tx = tx
					t.txETag = etag
					expired = t.tx.State != bitwrk.StateActive
					t.condition.Broadcast()
					log.Printf("Tx change detected: phase=%v, expired=%v", t.tx.Phase, expired)
				}
			}()
			if expired {
				break
			}
		}
	}
	return nil
}

// Manages the complete lifecycle of a sell
func (a *SellActivity) PerformSell(log bitwrk.Logger, receiveManager *ReceiveManager, interrupt <-chan bool) error {
	defer log.Println("Sell finished")
	err := a.doPerformSell(log, receiveManager, interrupt)
	if err != nil {
		a.lastError = err
	}
	a.alive = false
	return err
}

func (a *BuyActivity) sendMissingChunksAndReturnResult(log bitwrk.Logger, client *http.Client, wishList []byte, compressed bool) (io.ReadCloser, error) {
	// Send data of missing chunks to seller
	pipeIn, pipeOut := io.Pipe()
	defer pipeIn.Close()

	// Setup compression layer with dummy impl in case of uncompressed transmisison
	var compressor io.Writer
	var closeCompressor func() error
	if compressed {
		c := gzip.NewWriter(pipeOut)
		compressor = c
		closeCompressor = c.Close
	} else {
		compressor = pipeOut
		closeCompressor = func() error { return nil }
	}

	mwriter := multipart.NewWriter(compressor)

	// Communicate status back
	progressCallback := func(bytesToTransfer, bytesTransferred uint64) {
		a.execSync(func() {
			a.bytesToTransfer = bytesToTransfer
			a.bytesTransferred = bytesTransferred
		})
	}

	// Write work chunks into pipe for HTTP request
	go func() {
		defer pipeOut.Close()
		if part, err := mwriter.CreateFormFile("chunkdata", "chunkdata.bin"); err != nil {
			pipeOut.CloseWithError(err)
			return
		} else if err := cafs.WriteRequestedChunks(a.workFile, wishList, part, progressCallback); err != nil {
			pipeOut.CloseWithError(err)
			return
		}
		if err := mwriter.Close(); err != nil {
			pipeOut.CloseWithError(err)
			return
		}
		if err := closeCompressor(); err != nil {
			pipeOut.CloseWithError(err)
			return
		}
		log.Printf("Missing chunk data transmitted successfully.")
	}()

	if r, err := a.postToSeller(pipeIn, mwriter.FormDataContentType(), compressed, client); err != nil {
		return nil, fmt.Errorf("Error sending work chunk data to seller: %v", err)
	} else {
		return r, nil
	}
}

func (a *BuyActivity) transmitWorkChunked(log bitwrk.Logger, client *http.Client, compressed bool) (io.ReadCloser, error) {
	if r, err := a.requestMissingChunks(log.New("request missing chunks"), client); err != nil {
		return nil, err
	} else {
		defer r.Close()
		numChunks := a.workFile.NumChunks()
		if numChunks > MaxNumberOfChunksInWorkFile {
			return nil, fmt.Errorf("Work file too big: %d chunks (only %d allowed).", numChunks, MaxNumberOfChunksInWorkFile)
		}
		wishList := make([]byte, int(numChunks+7)/8)
		if _, err := io.ReadFull(r, wishList); err != nil {
			return nil, fmt.Errorf("Error decoding list of missing chunks: %v", err)
		}
		return a.sendMissingChunksAndReturnResult(log.New("send work chunk data"), client, wishList, compressed)
	}
}

func (a *BuyActivity) encodeChunkedFirstTransmission(log bitwrk.Logger, mwriter *multipart.Writer) (err error) {
	part, err := mwriter.CreateFormFile("a32chunks", "a32chunks.bin")
	if err != nil {
		return
	}
	log.Printf("Sending work chunk hashes to seller [%v].", *a.tx.WorkerURL)
	err = cafs.WriteChunkHashes(a.workFile, part)
	if err != nil {
		return
	}
	log.Printf("Sending buyer's secret to seller.")
	err = mwriter.WriteField("buyersecret", a.buyerSecret.String())
	if err != nil {
		return
	}
	return mwriter.Close()
}

// Closes resources upon exit of a function or when some condition no longer holds
// Arguments:
//  - exitChan: Signals the watchdog to exit
//  - closerChan: Signals the watchdog to add an io.Closer to the list of closers
//  - f: Defines the OK condition. When false, all current closers are closed
func (t *Trade) watchdog(log bitwrk.Logger, exitChan <-chan bool, closerChan <-chan io.Closer, f func() bool) {
	closers := make([]io.Closer, 0, 1)
	for {
		select {
		case closer := <-closerChan:
			closers = append(closers, closer)
		case <-exitChan:
			// Exit from watchdog if surrounding function has terminated
			log.Print("Watchdog exiting by request")
			return
		default:
		}

		// Check if condition still holds
		t.condition.L.Lock()
		ok := f()
		t.condition.L.Unlock()
		if !ok {
			log.Printf("Watchdog: closing %v channels", len(closers))
			for _, c := range closers {
				err := c.Close()
				if err != nil {
					log.Printf("Error closing channel: %v", err)
				}
			}
			closers = closers[:0] // clear list of current closers
		}

		time.Sleep(250 * time.Millisecond)
	}
}

func (s *WorkerState) offer(log bitwrk.Logger) {
	defer log.Printf("Stopped offering")
	s.cond.L.Lock()
	defer s.cond.L.Unlock()
	interrupt := make(chan bool, 1)
	for {
		// Interrupt if unregistered, stop iterating
		if s.Unregistered {
			log.Printf("No longer registered")
			interrupt <- true
			break
		}
		if s.Blockers == 0 {
			s.LastError = ""
			if sell, err := s.m.activityManager.NewSell(s); err != nil {
				s.LastError = fmt.Sprintf("Error creating sell: %v", err)
				log.Println(s.LastError)
				s.blockFor(20 * time.Second)
			} else {
				s.Blockers++
				go s.executeSell(log, sell, interrupt)
			}
		}
		s.cond.Wait()
	}
}

func (t *Trade) awaitTransaction(log bitwrk.Logger) error {
	lastETag := ""
	for count := 1; ; count++ {
		if bid, etag, err := FetchBid(t.bidId, lastETag); err != nil {
			return fmt.Errorf("Error in FetchBid awaiting transaction: %v", err)
		} else if bid != nil {
			log.Printf("Bid: %#v ETag: %v lastETag: %v", *bid, etag, lastETag)
			t.bid = bid
			lastETag = etag
			if t.bid.State == bitwrk.Matched {
				t.txId = *t.bid.Transaction
				break
			} else if t.bid.State == bitwrk.Expired {
				return ErrBidExpired
			}
		}

		// Sleep for gradually longer durations
		time.Sleep(time.Duration(count) * 500 * time.Millisecond)
	}
	return nil
}

func NewWorkReceiver(log bitwrk.Logger,
	info string,
	receiveManager *ReceiveManager,
	storage cafs.FileStorage,
	key bitwrk.Tkey,
	handler WorkHandler) WorkReceiver {
	result := &endpointReceiver{
		endpoint:     receiveManager.NewEndpoint(info),
		storage:      storage,
		log:          log,
		handler:      handler,
		info:         info,
		encResultKey: key,
	}
	result.endpoint.SetHandler(func(w http.ResponseWriter, r *http.Request) {
		if err := result.handleRequest(w, r); err != nil {
			http.Error(w, err.Error(), http.StatusInternalServerError)
			log.Printf("Error in request: %v", err)
			result.Dispose()
		}
	})
	return result
}

func NewWorkReceiver(log bitwrk.Logger,
	info string,
	receiveManager *ReceiveManager,
	storage cafs.FileStorage,
	key bitwrk.Tkey,
	handler WorkHandler) WorkReceiver {
	result := &endpointReceiver{
		endpoint:     receiveManager.NewEndpoint(info),
		storage:      storage,
		log:          log,
		handler:      handler,
		info:         info,
		encResultKey: key,
	}
	handlerFunc := func(w http.ResponseWriter, r *http.Request) {
		if err := result.handleRequest(w, r); err != nil {
			http.Error(w, err.Error(), http.StatusInternalServerError)
			log.Printf("Error in request: %v", err)
			result.doDispose(fmt.Errorf("Error handling request from %v: %v", r.RemoteAddr, err))
		}
	}
	result.endpoint.SetHandler(withCompression(handlerFunc))
	return result
}

// Polls the transaction state in a separate go-routine. Returns on abort signal, or
// when the polled transaction expires.
func (t *Trade) pollTransaction(log bitwrk.Logger, abort <-chan bool) {
	defer func() {
		log.Printf("Transaction polling has stopped")
	}()

	for count := 1; ; count++ {
		select {
		case <-abort:
			log.Printf("Aborting transaction polling while transaction active")
			return
		default:
		}

		if tx, etag, err := FetchTx(t.txId, ""); err != nil {
			log.Printf("Error polling transaction: %v", err)
		} else if etag != t.txETag {
			t.condition.L.Lock()
			t.tx = tx
			t.txETag = etag
			expired := t.tx.State != bitwrk.StateActive
			t.condition.Broadcast()
			t.condition.L.Unlock()
			log.Printf("Tx change detected: phase=%v, expired=%v", t.tx.Phase, expired)
			if expired {
				break
			}
		}

		// Sleep for gradually longer durations
		time.Sleep(time.Duration(count) * 500 * time.Millisecond)
	}

	log.Printf("Transaction has expired.")
	// This is necessary so that the surrounding function call doesn't deadlock
	<-abort
}

func (a *Trade) beginTrade(log bitwrk.Logger, interrupt <-chan bool) error {
	// wait for grant or reject
	log.Println("Waiting for permission")

	// Get a permission for the sell
	if err := a.awaitPermission(interrupt); err != nil {
		return fmt.Errorf("Error awaiting permission: %v", err)
	}
	log.Printf("Got permission. Price: %v", a.price)

	// Prevent too many unmatched bids on server
	key := fmt.Sprintf("%v-%v", a.bidType, a.article)
	if err := a.manager.checkoutToken(key, NumUnmatchedBids, interrupt); err != nil {
		return err
	}
	defer a.manager.returnToken(key)

	if err := a.awaitBid(); err != nil {
		return fmt.Errorf("Error awaiting bid: %v", err)
	}
	log.Printf("Got bid id: %v", a.bidId)

	if err := a.awaitTransaction(log); err != nil {
		return fmt.Errorf("Error awaiting transaction: %v", err)
	}
	log.Printf("Got transaction id: %v", a.txId)

	if tx, etag, err := FetchTx(a.txId, ""); err != nil {
		return err
	} else {
		a.tx = tx
		a.txETag = etag
	}

	return nil
}

func (s *WorkerState) executeSell(log bitwrk.Logger, sell *SellActivity, interrupt <-chan bool) {
	defer func() {
		s.cond.L.Lock()
		s.Blockers--
		s.cond.Broadcast()
		s.cond.L.Unlock()
	}()
	defer sell.Dispose()
	if err := sell.PerformSell(log.Newf("Sell #%v", sell.GetKey()), s.m.receiveManager, interrupt); err != nil {
		s.LastError = fmt.Sprintf("Error performing sell (delaying next sell by 20s): %v", err)
		log.Println(s.LastError)
		s.cond.L.Lock()
		s.blockFor(20 * time.Second)
		s.cond.L.Unlock()
	} else {
		log.Printf("Returned from PerformSell successfully")
	}
}