Method Read

api-get-object.go:377–428

Read reads up to len(b) bytes into b. It returns the number of bytes read (0 <= n <= len(b)) and any error encountered. Returns io.EOF upon end of file.

(b []byte)

// bytes read (0 <= n <= len(b)) and any error encountered. Returns
// io.EOF upon end of file.
func (o *Object) Read(b []byte) (n int, err error) {
	if o == nil {
		return 0, errInvalidArgument("Object is nil")
	}

	// Locking.
	o.mutex.Lock()
	defer o.mutex.Unlock()

	// prevErr is previous error saved from previous operation.
	if o.prevErr != nil || o.isClosed {
		return 0, o.prevErr
	}

	// Create a new request.
	readReq := getRequest{
		isReadOp: true,
		beenRead: o.beenRead,
		Buffer:   b,
	}

	// Alert that this is the first request.
	if !o.isStarted {
		readReq.isFirstReq = true
	}

	// Ask to establish a new data fetch routine based on seekData flag
	readReq.DidOffsetChange = o.seekData
	readReq.Offset = o.currOffset

	// Send and receive from the first request.
	response, err := o.doGetRequest(readReq)
	if err != nil && err != io.EOF {
		// Save the error for future calls.
		o.prevErr = err
		return response.Size, err
	}

	// Bytes read.
	bytesRead := int64(response.Size)

	// Set the new offset.
	oerr := o.setOffset(bytesRead)
	if oerr != nil {
		// Save the error for future calls.
		o.prevErr = oerr
		return response.Size, oerr
	}

	// Return the response.
	return response.Size, err
}

// Stat returns the ObjectInfo structure describing Object.
func (o *Object) Stat() (ObjectInfo, error) {