events

Documentation

Index

• Variables
• type EventErrorIterator
  • func (i *EventErrorIterator) Event() (*api.EventWrapper, error)
  • func (i *EventErrorIterator) Seek(eventID rlid.RLID) bool
• type EventIterator
  • func (i *EventIterator) Error() error
  • func (i *EventIterator) Event() (*api.EventWrapper, error)
  • func (t *EventIterator) Seek(eventID rlid.RLID) bool
• type IndashErrorIterator
  • func (i *IndashErrorIterator) Hash() ([]byte, error)
• type IndashIterator
  • func (i *IndashIterator) Error() error
  • func (i *IndashIterator) Hash() ([]byte, error)
• type Key
  • func CreateKey(topicID ulid.ULID, eventID rlid.RLID, segment Segment) (key Key, err error)
  • func EventKey(event *api.EventWrapper) (key Key, err error)
  • func MetaEventKey(event *api.EventWrapper) (key Key, err error)
  • func (k *Key) EventID() (eventID rlid.RLID)
  • func (k *Key) Segment() Segment
  • func (k *Key) TopicID() (topicID ulid.ULID)
• type Segment
  • func (s Segment) String() string
• type Store
  • func Open(conf config.StorageConfig) (store *Store, err error)
  • func (s *Store) ClearIndash(topicID ulid.ULID) error
  • func (s *Store) Close() error
  • func (s *Store) Count(slice *util.Range) (count uint64, err error)
  • func (s *Store) Destroy(topicID ulid.ULID) (err error)
  • func (s *Store) Indash(topicID ulid.ULID, hash []byte, eventID rlid.RLID) (err error)
  • func (s *Store) Insert(event *api.EventWrapper) (err error)
  • func (s *Store) List(topicID ulid.ULID) iterator.EventIterator
  • func (s *Store) LoadIndash(topicID ulid.ULID) iterator.IndashIterator
  • func (s *Store) ReadOnly() bool
  • func (s *Store) Retrieve(topicId ulid.ULID, eventID rlid.RLID) (event *api.EventWrapper, err error)
  • func (s *Store) Unhash(topicID ulid.ULID, hash []byte) (_ *api.EventWrapper, err error)

Variables

var (
	EventSegment     = Segment{0xdf, 0xb7}
	MetaEventSegment = Segment{0xd6, 0x8d}
	IndashSegment    = Segment{0xca, 0xac}
)

Segments in use by the Ensign event store

Types

type EventErrorIterator

type EventErrorIterator struct {
	errors.ErrorIterator
}

Implements iterator.EventIterator to return an error.

func (*EventErrorIterator) Event

func (i *EventErrorIterator) Event() (*api.EventWrapper, error)

func (*EventErrorIterator) Seek

func (i *EventErrorIterator) Seek(eventID rlid.RLID) bool

type EventIterator

type EventIterator struct {
	ldbiter.Iterator
	// contains filtered or unexported fields
}

Implements iterator.EventIterator to access to a sequence of events in a topic.

func (*EventIterator) Error

func (i *EventIterator) Error() error

func (*EventIterator) Event

func (i *EventIterator) Event() (*api.EventWrapper, error)

func (*EventIterator) Seek

func (t *EventIterator) Seek(eventID rlid.RLID) bool

type IndashErrorIterator

type IndashErrorIterator struct {
	errors.ErrorIterator
}

Implements iterator.IndashIterator to return an error.

func (*IndashErrorIterator) Hash

func (i *IndashErrorIterator) Hash() ([]byte, error)

type IndashIterator

type IndashIterator struct {
	ldbiter.Iterator
}

Implements iterator.IndashIterator to access a sequence of hashes for a topic.

func (*IndashIterator) Error

func (i *IndashIterator) Error() error

Error wraps an internal leveldb error so that ensign users can test against it.

func (*IndashIterator) Hash

func (i *IndashIterator) Hash() ([]byte, error)

Hash returns the key with the prefixed topic and segment stripped. If the key is not the right length then an error is returned but no other parsing happens.

type Key

type Key [28]byte

Key is is the 16 byte topic ID followed by a 2 byte segment that splits events from meta events then the 10 byte RLID for an event ID.

func CreateKey

func CreateKey(topicID ulid.ULID, eventID rlid.RLID, segment Segment) (key Key, err error)

func EventKey

func EventKey(event *api.EventWrapper) (key Key, err error)

func MetaEventKey

func MetaEventKey(event *api.EventWrapper) (key Key, err error)

func (*Key) EventID

func (k *Key) EventID() (eventID rlid.RLID)

EventID parses and returns the eventID RLID from the key.

func (*Key) Segment

func (k *Key) Segment() Segment

func (*Key) TopicID

func (k *Key) TopicID() (topicID ulid.ULID)

TopicID parses and returns the topicID ULID from the key.

type Segment

type Segment [2]byte

Segments ensure that a topic's events and meta events are stored contiguously.

func (Segment) String

func (s Segment) String() string

type Store

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

func Open

func Open(conf config.StorageConfig) (store *Store, err error)

func (*Store) ClearIndash

func (s *Store) ClearIndash(topicID ulid.ULID) error

ClearIndash deletes all of the index hashes for the the specified topic.

func (*Store) Close

func (s *Store) Close() error

func (*Store) Count

func (s *Store) Count(slice *util.Range) (count uint64, err error)

Count the number of objects that match the specified range by iterating through all of the keys and counting them. This is primarily used for testing.

func (*Store) Destroy

func (s *Store) Destroy(topicID ulid.ULID) (err error)

Destroy all events, meta-events, and index hashes of the specified topic. NOTE: this will destroy anything in the database that is prefixed with the topicID.

func (*Store) Indash

func (s *Store) Indash(topicID ulid.ULID, hash []byte, eventID rlid.RLID) (err error)

Indash stores an index hash of an event for duplicate detection purposes. In the underlying database, the indash key is the topicID + indashSegment + hash and the value is the eventID. Primarily the hashes are used to construct bloom filters for online duplicate detection, but the hash can also be used to lookup the event that represents the duplicate for equality comparison.

func (*Store) Insert

func (s *Store) Insert(event *api.EventWrapper) (err error)

Insert an event with the event segment into the database. If the event doesn't have an ID or a TopicID, an error is returned. This method also ensures that the localID is not stored and is nil. No other validation is performed by the database as this method is designed to write as quickly as possible.

func (*Store) List

func (s *Store) List(topicID ulid.ULID) iterator.EventIterator

Returns an iterator of events in the specified topic. If an offset RLID is specified

func (*Store) LoadIndash

func (s *Store) LoadIndash(topicID ulid.ULID) iterator.IndashIterator

LoadIndash returns an iterator that exposes all hashes in the database for the specified topicID. The iterator will strip off the topicID and segment from the key to return the Hash value.

func (*Store) ReadOnly

func (s *Store) ReadOnly() bool

func (*Store) Retrieve

func (s *Store) Retrieve(topicId ulid.ULID, eventID rlid.RLID) (event *api.EventWrapper, err error)

Retrieve a specific event from the database by topic and eventID.

func (*Store) Unhash

func (s *Store) Unhash(topicID ulid.ULID, hash []byte) (_ *api.EventWrapper, err error)

Unhash returns the event for the specified index hash (e.g. retrieving the original value from the hash using the event ID has as intermediate lookup).