datastore

package
v1.11.0 Latest Latest
Warning

This package is not in the latest version of its module.

 Go to latest Published: Aug 2, 2022 License: Apache-2.0 Imports: 14 Imported by: 1

Documentation

Index

Constants

View Source 
const Ellipsis = "..."

Ellipsis is a special relation that is assumed to be valid on the right hand side of a tuple.

Variables

View Source 
var Engines = []string{}

Functions

func BuildFinalizerFunction 

func BuildFinalizerFunction() func(iter *sliceRelationshipIterator)

BuildFinalizerFunction creates a function which can be used as a finalizer to make sure that tuples are getting closed before they are garbage collected.

func EngineOptions 

func EngineOptions() string

EngineOptions returns the full set of engine IDs, sorted and quoted into a string.

func NewInvalidRevisionErr 

func NewInvalidRevisionErr(revision Revision, reason InvalidRevisionReason) error

NewInvalidRevisionErr constructs a new invalid revision error.

func NewNamespaceNotFoundErr 

func NewNamespaceNotFoundErr(nsName string) error

NewNamespaceNotFoundErr constructs a new namespace not found error.

func NewReadonlyErr 

func NewReadonlyErr() error

NewReadonlyErr constructs an error for when a request has failed because the datastore has been configured to be read-only.

func NewWatchCanceledErr 

func NewWatchCanceledErr() error

NewWatchCanceledErr constructs a new watch was canceled error.

func NewWatchDisconnectedErr 

func NewWatchDisconnectedErr() error

NewWatchDisconnectedErr constructs a new watch was disconnected error.

func SeparateContextWithTracing 

func SeparateContextWithTracing(ctx context.Context) context.Context

SeparateContextWithTracing is a utility method which allows for severing the context between grpc and the datastore to prevent context cancellation from killing database connections that should otherwise go back to the connection pool.

func SortedEngineIDs 

func SortedEngineIDs() []string

SortedEngineIDs returns the full set of engine IDs, sorted.

Types

type Datastore 

type Datastore interface {
	// SnapshotRead creates a read-only handle that reads the datastore at the specified revision.
	// Any errors establishing the reader will be returned by subsequent calls.
	SnapshotReader(Revision) Reader

	// ReadWriteTx tarts a read/write transaction, which will be committed if no error is
	// returned and rolled back if an error is returned.
	ReadWriteTx(context.Context, TxUserFunc) (Revision, error)

	// OptimizedRevision gets a revision that will likely already be replicated
	// and will likely be shared amongst many queries.
	OptimizedRevision(ctx context.Context) (Revision, error)

	// HeadRevision gets a revision that is guaranteed to be at least as fresh as
	// right now.
	HeadRevision(ctx context.Context) (Revision, error)

	// CheckRevision checks the specified revision to make sure it's valid and
	// hasn't been garbage collected.
	CheckRevision(ctx context.Context, revision Revision) error

	// Watch notifies the caller about all changes to tuples.
	//
	// All events following afterRevision will be sent to the caller.
	Watch(ctx context.Context, afterRevision Revision) (<-chan *RevisionChanges, <-chan error)

	// IsReady returns whether the datastore is ready to accept data. Datastores that require
	// database schema creation will return false until the migrations have been run to create
	// the necessary tables.
	IsReady(ctx context.Context) (bool, error)

	// Features returns an object representing what features this
	// datastore can support.
	Features(ctx context.Context) (*Features, error)

	// Statistics returns relevant values about the data contained in this cluster.
	Statistics(ctx context.Context) (Stats, error)

	// Close closes the data store.
	Close() error
}

Datastore represents tuple access for a single namespace.

type ErrInvalidRevision 

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

ErrInvalidRevision occurs when a revision specified to a call was invalid.

func (ErrInvalidRevision) InvalidRevision 

func (eri ErrInvalidRevision) InvalidRevision() Revision

InvalidRevision is the revision that failed.

func (ErrInvalidRevision) MarshalZerologObject 

func (eri ErrInvalidRevision) MarshalZerologObject(e *zerolog.Event)

MarshalZerologObject implements zerolog object marshalling.

func (ErrInvalidRevision) Reason 

func (eri ErrInvalidRevision) Reason() InvalidRevisionReason

Reason is the reason the revision failed.

type ErrNamespaceNotFound 

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

ErrNamespaceNotFound occurs when a namespace was not found.

func (ErrNamespaceNotFound) MarshalZerologObject 

func (enf ErrNamespaceNotFound) MarshalZerologObject(e *zerolog.Event)

MarshalZerologObject implements zerolog object marshalling.

func (ErrNamespaceNotFound) NotFoundNamespaceName 

func (enf ErrNamespaceNotFound) NotFoundNamespaceName() string

NotFoundNamespaceName is the name of the namespace not found.

type ErrReadOnly 

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

ErrReadOnly is returned when the operation cannot be completed because the datastore is in read-only mode.

type ErrWatchCanceled 

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

ErrWatchCanceled occurs when a watch was canceled by the caller

type ErrWatchDisconnected 

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

ErrWatchDisconnected occurs when a watch has fallen too far behind and was forcibly disconnected as a result.

type Feature added in v1.11.0 

type Feature struct {
	Enabled bool
	Reason  string
}

Feature represents a capability that a datastore can support, plus an optional message explaining the feature is available (or not).

type Features added in v1.11.0 

type Features struct {
	// Watch is enabled if the underlying datastore can support the Watch api.
	Watch Feature
}

Features holds values that represent what features a database can support.

type InvalidRevisionReason 

type InvalidRevisionReason int

InvalidRevisionReason is the reason the revision could not be used. 

const (
	// RevisionStale is the reason returned when a revision is outside the window of
	// validity by being too old.
	RevisionStale InvalidRevisionReason = iota

	// RevisionInFuture is the reason returned when a revision is outside the window of
	// validity by being too new.
	RevisionInFuture

	// CouldNotDetermineRevision is the reason returned when a revision for a
	// request could not be determined.
	CouldNotDetermineRevision
)

type ObjectTypeStat 

type ObjectTypeStat struct {
	// NumRelations is the number of relations defined in a single object type.
	NumRelations uint32

	// NumPermissions is the number of permissions defined in a single object type.
	NumPermissions uint32
}

ObjectTypeStat represents statistics for a single object type (namespace).

func ComputeObjectTypeStats 

func ComputeObjectTypeStats(objTypes []*core.NamespaceDefinition) []ObjectTypeStat

ComputeObjectTypeStats creates a list of object type stats from an input list of parsed object types.

type ReadWriteTransaction 

type ReadWriteTransaction interface {
	Reader

	// WriteRelationships takes a list of tuple mutations and applies them to the datastore.
	WriteRelationships(mutations []*v1.RelationshipUpdate) error

	// DeleteRelationships deletes all Relationships that match the provided filter.
	DeleteRelationships(filter *v1.RelationshipFilter) error

	// WriteNamespaces takes proto namespace definitions and persists them.
	WriteNamespaces(newConfigs ...*core.NamespaceDefinition) error

	// DeleteNamespace deletes a namespace and any associated tuples.
	DeleteNamespace(nsName string) error
}

type Reader 

type Reader interface {
	// QueryRelationships reads relationships, starting from the resource side.
	QueryRelationships(
		ctx context.Context,
		filter *v1.RelationshipFilter,
		options ...options.QueryOptionsOption,
	) (RelationshipIterator, error)

	// ReverseQueryRelationships reads relationships, starting from the subject.
	ReverseQueryRelationships(
		ctx context.Context,
		subjectFilter SubjectsFilter,
		options ...options.ReverseQueryOptionsOption,
	) (RelationshipIterator, error)

	// ReadNamespace reads a namespace definition and the revision at which it was created or
	// last written. It returns an instance of ErrNamespaceNotFound if not found.
	ReadNamespace(ctx context.Context, nsName string) (ns *core.NamespaceDefinition, lastWritten Revision, err error)

	// ListNamespaces lists all namespaces defined.
	ListNamespaces(ctx context.Context) ([]*core.NamespaceDefinition, error)
}

type RelationshipIterator 

type RelationshipIterator interface {
	// Next returns the next tuple in the result set.
	Next() *core.RelationTuple

	// After receiving a nil response, the caller must check for an error.
	Err() error

	// Close cancels the query and closes any open connections.
	Close()
}

RelationshipIterator is an iterator over matched tuples.

func NewSliceRelationshipIterator 

func NewSliceRelationshipIterator(tuples []*core.RelationTuple) RelationshipIterator

NewSliceRelationshipIterator creates a datastore.TupleIterator instance from a materialized slice of tuples.

type Revision 

type Revision = decimal.Decimal

Revision is a type alias to make changing the revision type a little bit easier if we need to do it in the future. Implementations should code directly against decimal.Decimal when creating or parsing. 

var NoRevision Revision

NoRevision is a zero type for the revision that will make changing the revision type in the future a bit easier if necessary. Implementations should use any time they want to signal an empty/error revision.

type RevisionChanges 

type RevisionChanges struct {
	Revision Revision
	Changes  []*core.RelationTupleUpdate
}

RevisionChanges represents the changes in a single transaction.

type Stats 

type Stats struct {
	// UniqueID is a unique string for a single datastore.
	UniqueID string

	// EstimatedRelationshipCount is a best-guess estimate of the number of relationships
	// in the datstore. Computing it should use a lightweight method such as reading
	// table statistics.
	EstimatedRelationshipCount uint64

	// ObjectTypeStatistics returns a slice element for each object type (namespace)
	// stored in the datastore.
	ObjectTypeStatistics []ObjectTypeStat
}

Stats represents statistics for the entire datastore.

type SubjectRelationFilter added in v1.11.0 

type SubjectRelationFilter struct {
	// NonEllipsisRelation is the relation of the subject type to find. If empty,
	// IncludeEllipsisRelation must be true.
	NonEllipsisRelation string

	// IncludeEllipsisRelation, if true, indicates that the ellipsis relation
	// should be included as an option.
	IncludeEllipsisRelation bool
}

SubjectRelationFilter is the filter to use for relation(s) of subjects being queried.

func (SubjectRelationFilter) IsEmpty added in v1.11.0 

func (sf SubjectRelationFilter) IsEmpty() bool

IsEmpty returns true if the subject relation filter is empty.

func (SubjectRelationFilter) WithEllipsisRelation added in v1.11.0 

func (sf SubjectRelationFilter) WithEllipsisRelation() SubjectRelationFilter

WithEllipsisRelation indicates that the subject filter should include the ellipsis relation as an option for the subjects' relation.

func (SubjectRelationFilter) WithNonEllipsisRelation added in v1.11.0 

func (sf SubjectRelationFilter) WithNonEllipsisRelation(relation string) SubjectRelationFilter

WithNonEllipsisRelation indicates that the specified non-ellipsis relation should be included as an option for the subjects' relation.

type SubjectsFilter added in v1.11.0 

type SubjectsFilter struct {
	// SubjectType is the namespace/type for the subjects to be found.
	SubjectType string

	// SubjectIds are the IDs of the subjects to find. If empty, any subjects ID will be allowed.
	SubjectIds []string

	// RelationFilter is the filter to use for the relation(s) of the subjects. If neither field
	// is set, any relation is allowed.
	RelationFilter SubjectRelationFilter
}

SubjectsFilter is a filter for subjects.

type TxUserFunc 

type TxUserFunc func(context.Context, ReadWriteTransaction) error

TxUserFunc is a type for the function that users supply when they invoke a read-write transaction.

Source Files

View all Source files

Directories

Path Synopsis

Jump to

Keyboard shortcuts

? : This menu
/ : Search site
f or F : Jump to
y or Y : Canonical URL
go.dev uses cookies from Google to deliver and enhance the quality of its services and to analyze traffic. Learn more.