sourceReader

Documentation

Index

• Constants
• Variables
• type EventReader
  • func NewEventReader(src string, replset string) *EventReader
  • func (er *EventReader) EnsureNetwork() error
  • func (er *EventReader) Name() string
  • func (er *EventReader) Next() ([]byte, error)
  • func (er *EventReader) SetQueryTimestampOnEmpty(ts bson.MongoTimestamp)
  • func (er *EventReader) StartFetcher()
  • func (er *EventReader) String() string
  • func (er *EventReader) UpdateQueryTimestamp(ts bson.MongoTimestamp)
• type GidOplogReader
  • func NewGidOplogReader(src string) *GidOplogReader
  • func (reader *GidOplogReader) SetQueryGid(gid string)
• type OplogReader
  • func NewOplogReader(src string, replset string) *OplogReader
  • func (or *OplogReader) EnsureNetwork() (err error)
  • func (or *OplogReader) Name() string
  • func (or *OplogReader) Next() ([]byte, error)
  • func (or *OplogReader) NextOplog() (log *oplog.GenericOplog, err error)
  • func (or *OplogReader) SetQueryTimestampOnEmpty(ts bson.MongoTimestamp)
  • func (or *OplogReader) StartFetcher()
  • func (or *OplogReader) String() string
  • func (or *OplogReader) UpdateQueryTimestamp(ts bson.MongoTimestamp)
• type Reader
  • func CreateReader(fetchMethod string, src string, replset string) (Reader, error)

Constants

const (
	QueryTs    = "ts"
	QueryGid   = "g"
	QueryOpGT  = "$gt"
	QueryOpGTE = "$gte"
)

const (
	ErrInvalidStartPosition = "resume point may no longer be in the oplog."
)

Variables

var (
	BatchSize       = 8192
	PrefetchPercent = 0.2
)

var CollectionCappedError = errors.New("collection capped error")

var TimeoutError = errors.New("read next log timeout, It shouldn't be happen")

TimeoutError. mongodb query executed timeout

Types

type EventReader

type EventReader struct {
	// contains filtered or unexported fields
}

func NewEventReader

func NewEventReader(src string, replset string) *EventReader

NewEventReader creates reader with mongodb url

func (*EventReader) EnsureNetwork

func (er *EventReader) EnsureNetwork() error

func (*EventReader) Name

func (er *EventReader) Name() string

func (*EventReader) Next

func (er *EventReader) Next() ([]byte, error)

Next returns an oplog by raw bytes which is []byte

func (*EventReader) SetQueryTimestampOnEmpty

func (er *EventReader) SetQueryTimestampOnEmpty(ts bson.MongoTimestamp)

SetQueryTimestampOnEmpty set internal timestamp if not exist in this or. initial stage most of the time

func (*EventReader) StartFetcher

func (er *EventReader) StartFetcher()

start fetcher if not exist

func (*EventReader) String

func (er *EventReader) String() string

func (*EventReader) UpdateQueryTimestamp

func (er *EventReader) UpdateQueryTimestamp(ts bson.MongoTimestamp)

type GidOplogReader

type GidOplogReader struct {
	OplogReader
}

GidOplogReader. query along with gid

func NewGidOplogReader

func NewGidOplogReader(src string) *GidOplogReader

func (*GidOplogReader) SetQueryGid

func (reader *GidOplogReader) SetQueryGid(gid string)

type OplogReader

type OplogReader struct {
	// contains filtered or unexported fields
}

OplogReader represents stream reader from mongodb that specified by an url. And with query options. user can iterate oplogs.

func NewOplogReader

func NewOplogReader(src string, replset string) *OplogReader

NewOplogReader creates reader with mongodb url

func (*OplogReader) EnsureNetwork

func (or *OplogReader) EnsureNetwork() (err error)

ensureNetwork establish the mongodb connection at first if current connection is not ready or disconnected

func (*OplogReader) Name

func (or *OplogReader) Name() string

func (*OplogReader) Next

func (or *OplogReader) Next() ([]byte, error)

Next returns an oplog by raw bytes which is []byte

func (*OplogReader) NextOplog

func (or *OplogReader) NextOplog() (log *oplog.GenericOplog, err error)

NextOplog returns an oplog by oplog.GenericOplog struct

func (*OplogReader) SetQueryTimestampOnEmpty

func (or *OplogReader) SetQueryTimestampOnEmpty(ts bson.MongoTimestamp)

SetQueryTimestampOnEmpty set internal timestamp if not exist in this or. initial stage most of the time

func (*OplogReader) StartFetcher

func (or *OplogReader) StartFetcher()

start fetcher if not exist

func (*OplogReader) String

func (or *OplogReader) String() string

func (*OplogReader) UpdateQueryTimestamp

func (or *OplogReader) UpdateQueryTimestamp(ts bson.MongoTimestamp)

type Reader

type Reader interface {
	Name() string                                 // reader name
	StartFetcher()                                // start fetcher
	SetQueryTimestampOnEmpty(bson.MongoTimestamp) // set query timestamp when first start
	UpdateQueryTimestamp(bson.MongoTimestamp)     // update query timestamp
	Next() ([]byte, error)                        // fetch next oplog/event
	EnsureNetwork() error                         // ensure network
}

func CreateReader

func CreateReader(fetchMethod string, src string, replset string) (Reader, error)