protocol

Documentation

Overview

Package protocol describes the wire protocol between workers, document managers and search agents. The actual NATS messages are JSON-encoded versions of the types defined here.

Index

• Variables
• type CloneRequest
• type CloneStream
• type Document
• type DocumentID
• type DocumentReference
• type DocumentRequest
• type DocumentUpdate
• type IndexStatus
  • func (status IndexStatus) String() string
• type IndexStatusCode
  • func (isc IndexStatusCode) String() string
• type IndexUpdate
• type IndexUpdateRequest
• type Metrics
• type MetricsRequest
• type SearchHit
• type SearchRequest
• type SearchResponse
• type SearchResult
• type SearchStatusCode
  • func (ssc SearchStatusCode) String() string
• type Semver
  • func ParseSemver(version string) (result Semver, err error)
  • func (v Semver) CompatibleWith(other Semver) bool
  • func (v Semver) NewerThan(other Semver) bool
  • func (v Semver) String() string

Variables

var Version = Semver{0, 5, 0}

Version of the wire protocol

Types

type CloneRequest

type CloneRequest struct {
	SourceShard string
	TargetShard string
}

A CloneRequest is sent by freshly started workers that want to initialize by cloning another index.

type CloneStream

type CloneStream struct {
	URL string
}

CloneStream is sent in response to a CloneRequest. The returned URL can be read only once and is valid for a limited time.

type Document

type Document struct {
	ID      DocumentID
	Updated time.Time
	Title   string
	Text    string
	Alive   bool
}

Document is the representation of a searchable item

type DocumentID

type DocumentID string

DocumentID is just a string, could be uuid, hash, numeric, et.c.

type DocumentReference

type DocumentReference struct {
	ID      DocumentID
	Updated time.Time
}

A DocumentReference corresponds to one document at one point in time

type DocumentRequest

type DocumentRequest struct {
	Space  string
	Wanted []DocumentID
}

A DocumentRequest is a request for a list of documents. Returned documents are broadcasted to all workers.

type DocumentUpdate

type DocumentUpdate struct {
	Space     string
	Documents []Document
}

A DocumentUpdate is sent in response to DocumentRequest

type IndexStatus

type IndexStatus struct {
	IndexID        string
	Version        string
	DocCount       uint64
	LastUpdate     time.Time
	ShardgroupSize uint16
	ShardIndex     uint16
	Status         IndexStatusCode
}

IndexStatus is regularly broadcast from all workers

func (IndexStatus) String

func (status IndexStatus) String() string

type IndexStatusCode

type IndexStatusCode uint8

IndexStatusCode is what is says

const (
	IndexStatusInSync IndexStatusCode = iota + 72
	IndexStatusSyncing
	IndexStatusStartingUp
	IndexStatusIncompleteShardgroup
	IndexStatusIncompatible
)

Codes returned in index status updates. There is only one status level at any given time, with higher valued codes overriding lower valued codes.

func (IndexStatusCode) String

func (isc IndexStatusCode) String() string

type IndexUpdate

type IndexUpdate struct {
	Space   string
	Updates []DocumentReference
}

A IndexUpdate is a list of updated documents, sent in response to the IndexUpdateRequest above.

type IndexUpdateRequest

type IndexUpdateRequest struct {
	Space         string
	FromTime      time.Time
	AfterDocument DocumentID
	Limit         uint16
}

IndexUpdateRequest is a request for available updates. Returns up to 'Limit' document IDs, updated at or later than the specified document or timestamp.

type Metrics

type Metrics struct {
	RequestID  string
	IndexID    string
	Updated    time.Time
	PackedJSON string
}

Metrics holds a metrics response from one service instance. The RequestID field contains the ID provided in the corresponding request. The PackedJSON field contains Base64 encoded, zlib compressed JSON of all exported metrics.

type MetricsRequest

type MetricsRequest struct {
	RequestID string
}

MetricsRequest asks for a metrics dump from all service instances

type SearchHit

type SearchHit struct {
	Space   string
	ID      DocumentID
	Snippet string
	Rank    float32
}

SearchHit represents one search hit

type SearchRequest

type SearchRequest struct {
	// Spaces to search
	Spaces []string
	// Query string in letarette syntax
	Query string
	// Maximum number of hits returned in one page
	PageLimit uint16
	// Zero-indexed page of hits to retrieve
	PageOffset uint16
	// When true, spelling mistakes are "fixed"
	// and the resulting query is automatically performed.
	// In either case, spell-fixed queries are returned
	// in the SearchResult Respelt field.
	Autocorrect bool
}

A SearchRequest is sent from a search handler to search the index.

type SearchResponse

type SearchResponse struct {
	Result   SearchResult
	Duration float32
	Status   SearchStatusCode
}

SearchResponse is sent in response to SearchRequest

type SearchResult

type SearchResult struct {
	Hits []SearchHit
	// When true, the search was truncated
	// Capped results are only locally sorted by rank
	Capped bool
	// When not empty, the original query had no matches,
	// and this is a respelt version of the query
	Respelt string
	// The summed Levenshtein distance for all respelt terms
	RespeltDistance float32
	// The total number of hits to the given query
	TotalHits int
}

SearchResult is a collection of search hits

type SearchStatusCode

type SearchStatusCode uint8

SearchStatusCode is what is says

const (
	SearchStatusNoHit SearchStatusCode = iota + 42
	SearchStatusCacheHit
	SearchStatusIndexHit
	SearchStatusTimeout
	SearchStatusQueryError
	SearchStatusServerError
)

Codes returned in search responses

func (SearchStatusCode) String

func (ssc SearchStatusCode) String() string

type Semver

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

Semver is used for protocol versioning

func ParseSemver

func ParseSemver(version string) (result Semver, err error)

ParseSemver creates a Semver struct from a string

func (Semver) CompatibleWith

func (v Semver) CompatibleWith(other Semver) bool

CompatibleWith returns true when major versions match

func (Semver) NewerThan

func (v Semver) NewerThan(other Semver) bool

NewerThan returns true when this version is newer than the other

func (Semver) String

func (v Semver) String() string