database

package
v0.5.6 Latest Latest
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 Go to latest Published: Nov 22, 2024 License: Apache-2.0 Imports: 16 Imported by: 1

Documentation

Overview

Package database provides the database interface for the Yorkie backend.

Index

Constants

View Source 
const (
	ClientDeactivated = "deactivated"
	ClientActivated   = "activated"
)

Below are statuses of the client.

View Source 
const (
	DocumentAttached = "attached"
	DocumentDetached = "detached"
	DocumentRemoved  = "removed"
)

Below are statuses of the document.

Variables

View Source 
var (
	ErrClientNotActivated      = errors.New("client not activated")
	ErrDocumentNotAttached     = errors.New("document not attached")
	ErrDocumentNeverAttached   = errors.New("client has never attached the document")
	ErrDocumentAlreadyAttached = errors.New("document already attached")
	ErrDocumentAlreadyDetached = errors.New("document already detached")
	ErrAttachedDocumentExists  = errors.New("attached document exits when deactivated")
)

Below are the errors may occur depending on the document and client status.

View Source 
var (
	// ErrProjectAlreadyExists is returned when the project already exists.
	ErrProjectAlreadyExists = errors.New("project already exists")

	// ErrUserNotFound is returned when the user is not found.
	ErrUserNotFound = errors.New("user not found")

	// ErrProjectNotFound is returned when the project is not found.
	ErrProjectNotFound = errors.New("project not found")

	// ErrUserAlreadyExists is returned when the user already exists.
	ErrUserAlreadyExists = errors.New("user already exists")

	// ErrClientNotFound is returned when the client could not be found.
	ErrClientNotFound = errors.New("client not found")

	// ErrDocumentNotFound is returned when the document could not be found.
	ErrDocumentNotFound = errors.New("document not found")

	// ErrChangeNotFound is returned when the change could not be found.
	ErrChangeNotFound = errors.New("change not found")

	// ErrSnapshotNotFound is returned when the snapshot could not be found.
	ErrSnapshotNotFound = errors.New("snapshot not found")

	// ErrConflictOnUpdate is returned when a conflict occurs during update.
	ErrConflictOnUpdate = errors.New("conflict on update")

	// ErrProjectNameAlreadyExists is returned when the project name already exists.
	ErrProjectNameAlreadyExists = errors.New("project name already exists")
)
View Source 
var DefaultProjectID = types.ID("000000000000000000000000")

DefaultProjectID is the default project ID.

View Source 
var DefaultProjectName = "default"

DefaultProjectName is the default project name.

View Source 
var ErrDecodeOperationFailed = errors.New("decode operations failed")

ErrDecodeOperationFailed is returned when decoding operations failed.

View Source 
var ErrEncodeOperationFailed = errors.New("encode operations failed")

ErrEncodeOperationFailed is returned when encoding operations failed.

View Source 
var ErrInvalidTimeDurationString = errors.New("invalid time duration string format")

ErrInvalidTimeDurationString is returned when the given time duration string is not in valid format.

View Source 
var (
	// ErrMismatchedPassword is returned when the password is mismatched.
	ErrMismatchedPassword = fmt.Errorf("mismatched password")
)

Functions

func CompareHashAndPassword added in v0.2.14 

func CompareHashAndPassword(hashed, password string) error

CompareHashAndPassword compares the hashed password and the password.

func EncodeOperations 

func EncodeOperations(operations []operations.Operation) ([][]byte, error)

EncodeOperations encodes the given operations into bytes array.

func EncodePresenceChange added in v0.4.5 

func EncodePresenceChange(p *innerpresence.PresenceChange) ([]byte, error)

EncodePresenceChange encodes the given PresenceChange into bytes array.

func HashedPassword added in v0.2.14 

func HashedPassword(password string) (string, error)

HashedPassword hashes the given password.

func PresenceChangeFromBytes added in v0.5.6 

func PresenceChangeFromBytes(bytes []byte) (*innerpresence.PresenceChange, error)

PresenceChangeFromBytes decodes the given bytes array into PresenceChange.

Types

type ChangeInfo 

type ChangeInfo struct {
	ID             types.ID                      `bson:"_id"`
	ProjectID      types.ID                      `bson:"project_id"`
	DocID          types.ID                      `bson:"doc_id"`
	ServerSeq      int64                         `bson:"server_seq"`
	ClientSeq      uint32                        `bson:"client_seq"`
	Lamport        int64                         `bson:"lamport"`
	ActorID        types.ID                      `bson:"actor_id"`
	VersionVector  time.VersionVector            `bson:"version_vector"`
	Message        string                        `bson:"message"`
	Operations     [][]byte                      `bson:"operations"`
	PresenceChange *innerpresence.PresenceChange `bson:"presence_change"`
}

ChangeInfo is a structure representing information of a change.

func (*ChangeInfo) DeepCopy added in v0.3.4 

func (i *ChangeInfo) DeepCopy() *ChangeInfo

DeepCopy returns a deep copy of this ChangeInfo.

func (*ChangeInfo) ToChange 

func (i *ChangeInfo) ToChange() (*change.Change, error)

ToChange creates Change model from this ChangeInfo.

type ClientDocInfo 

type ClientDocInfo struct {
	Status    string `bson:"status"`
	ServerSeq int64  `bson:"server_seq"`
	ClientSeq uint32 `bson:"client_seq"`
}

ClientDocInfo is a structure representing information of the document attached to the client.

type ClientDocInfoMap added in v0.4.14 

type ClientDocInfoMap map[types.ID]*ClientDocInfo

ClientDocInfoMap is a map that associates DocRefKey with ClientDocInfo instances.

type ClientInfo 

type ClientInfo struct {
	// ID is the unique ID of the client.
	ID types.ID `bson:"_id"`

	// ProjectID is the ID of the project the client belongs to.
	ProjectID types.ID `bson:"project_id"`

	// Key is the key of the client. It is used to identify the client by users.
	Key string `bson:"key"`

	// Status is the status of the client.
	Status string `bson:"status"`

	// Documents is a map of document which is attached to the client.
	Documents ClientDocInfoMap `bson:"documents"`

	// CreatedAt is the time when the client was created.
	CreatedAt time.Time `bson:"created_at"`

	// UpdatedAt is the last time the client was accessed.
	// NOTE(hackerwins): The field name is "updated_at" but it is used as
	// "accessed_at".
	UpdatedAt time.Time `bson:"updated_at"`
}

ClientInfo is a structure representing information of a client.

func (*ClientInfo) AttachDocument 

func (i *ClientInfo) AttachDocument(docID types.ID, alreadyAttached bool) error

AttachDocument attaches the given document to this client.

func (*ClientInfo) CheckIfInProject 

func (i *ClientInfo) CheckIfInProject(projectID types.ID) error

CheckIfInProject checks if the client is in the project.

func (*ClientInfo) Checkpoint 

func (i *ClientInfo) Checkpoint(docID types.ID) change.Checkpoint

Checkpoint returns the checkpoint of the given document.

func (*ClientInfo) Deactivate 

func (i *ClientInfo) Deactivate()

Deactivate sets the status of this client to be deactivated.

func (*ClientInfo) DeepCopy 

func (i *ClientInfo) DeepCopy() *ClientInfo

DeepCopy returns a deep copy of this client info.

func (*ClientInfo) DetachDocument 

func (i *ClientInfo) DetachDocument(docID types.ID) error

DetachDocument detaches the given document from this client.

func (*ClientInfo) EnsureActivated added in v0.4.21 

func (i *ClientInfo) EnsureActivated() error

EnsureActivated ensures the client is activated.

func (*ClientInfo) EnsureDocumentAttached 

func (i *ClientInfo) EnsureDocumentAttached(docID types.ID) error

EnsureDocumentAttached ensures the given document is attached.

func (*ClientInfo) EnsureDocumentsNotAttachedWhenDeactivated added in v0.4.25 

func (i *ClientInfo) EnsureDocumentsNotAttachedWhenDeactivated() error

EnsureDocumentsNotAttachedWhenDeactivated ensures that no documents are attached when the client is deactivated.

func (*ClientInfo) IsAttached 

func (i *ClientInfo) IsAttached(docID types.ID) (bool, error)

IsAttached returns whether the given document is attached to this client.

func (*ClientInfo) RefKey added in v0.4.14 

func (i *ClientInfo) RefKey() types.ClientRefKey

RefKey returns the refKey of the client.

func (*ClientInfo) RemoveDocument added in v0.3.3 

func (i *ClientInfo) RemoveDocument(docID types.ID) error

RemoveDocument removes the given document from this client.

func (*ClientInfo) ServerSeq added in v0.5.2 

func (i *ClientInfo) ServerSeq(
	docID types.ID,
) (int64, error)

ServerSeq returns the server sequence of the given document.

func (*ClientInfo) UpdateCheckpoint 

func (i *ClientInfo) UpdateCheckpoint(
	docID types.ID,
	cp change.Checkpoint,
) error

UpdateCheckpoint updates the checkpoint of the given document.

type Database 

type Database interface {
	// Close all resources of this database.
	Close() error

	// FindProjectInfoByPublicKey returns a project by public key.
	FindProjectInfoByPublicKey(
		ctx context.Context,
		publicKey string,
	) (*ProjectInfo, error)

	// FindProjectInfoBySecretKey returns a project by secret key.
	FindProjectInfoBySecretKey(
		ctx context.Context,
		secretKey string,
	) (*ProjectInfo, error)

	// FindProjectInfoByName returns a project by the given name.
	FindProjectInfoByName(
		ctx context.Context,
		owner types.ID,
		name string,
	) (*ProjectInfo, error)

	// FindProjectInfoByID returns a project by the given id. It should not be
	// used directly by clients because it is not checked if the project is
	// permitted to be accessed by the admin client.
	FindProjectInfoByID(ctx context.Context, id types.ID) (*ProjectInfo, error)

	// EnsureDefaultUserAndProject ensures that the default user and project
	// exists.
	EnsureDefaultUserAndProject(
		ctx context.Context,
		username,
		password string,
		clientDeactivateThreshold string,
	) (*UserInfo, *ProjectInfo, error)

	// CreateProjectInfo creates a new project.
	CreateProjectInfo(
		ctx context.Context,
		name string,
		owner types.ID,
		clientDeactivateThreshold string,
	) (*ProjectInfo, error)

	// ListProjectInfos returns all project infos owned by owner.
	ListProjectInfos(ctx context.Context, owner types.ID) ([]*ProjectInfo, error)

	// UpdateProjectInfo updates the project.
	UpdateProjectInfo(
		ctx context.Context,
		owner types.ID,
		id types.ID,
		fields *types.UpdatableProjectFields,
	) (*ProjectInfo, error)

	// CreateUserInfo creates a new user.
	CreateUserInfo(
		ctx context.Context,
		username string,
		hashedPassword string,
	) (*UserInfo, error)

	// DeleteUserInfoByName deletes a user by name.
	DeleteUserInfoByName(ctx context.Context, username string) error

	// ChangeUserPassword changes to new password for user.
	ChangeUserPassword(ctx context.Context, username, hashedNewPassword string) error

	// FindUserInfoByID returns a user by the given ID.
	FindUserInfoByID(ctx context.Context, id types.ID) (*UserInfo, error)

	// FindUserInfoByName returns a user by the given username.
	FindUserInfoByName(ctx context.Context, username string) (*UserInfo, error)

	// ListUserInfos returns all users.
	ListUserInfos(ctx context.Context) ([]*UserInfo, error)

	// ActivateClient activates the client of the given key.
	ActivateClient(ctx context.Context, projectID types.ID, key string) (*ClientInfo, error)

	// DeactivateClient deactivates the client of the given refKey.
	DeactivateClient(ctx context.Context, refKey types.ClientRefKey) (*ClientInfo, error)

	// FindClientInfoByRefKey finds the client of the given refKey.
	FindClientInfoByRefKey(ctx context.Context, refKey types.ClientRefKey) (*ClientInfo, error)

	// UpdateClientInfoAfterPushPull updates the client from the given clientInfo
	// after handling PushPull.
	UpdateClientInfoAfterPushPull(ctx context.Context, clientInfo *ClientInfo, docInfo *DocInfo) error

	// FindNextNCyclingProjectInfos finds the next N cycling projects from the given projectID.
	FindNextNCyclingProjectInfos(
		ctx context.Context,
		pageSize int,
		lastProjectID types.ID,
	) ([]*ProjectInfo, error)

	// FindDeactivateCandidatesPerProject finds the clients that need housekeeping per project.
	FindDeactivateCandidatesPerProject(
		ctx context.Context,
		project *ProjectInfo,
		candidatesLimit int,
	) ([]*ClientInfo, error)

	// FindDocInfoByKey finds the document of the given key.
	FindDocInfoByKey(
		ctx context.Context,
		projectID types.ID,
		docKey key.Key,
	) (*DocInfo, error)

	// FindDocInfosByKeys finds the documents of the given keys.
	FindDocInfosByKeys(
		ctx context.Context,
		projectID types.ID,
		docKeys []key.Key,
	) ([]*DocInfo, error)

	// FindDocInfoByKeyAndOwner finds the document of the given key. If the
	// createDocIfNotExist condition is true, create the document if it does not
	// exist.
	FindDocInfoByKeyAndOwner(
		ctx context.Context,
		clientRefKey types.ClientRefKey,
		docKey key.Key,
		createDocIfNotExist bool,
	) (*DocInfo, error)

	// FindDocInfoByRefKey finds the document of the given refKey.
	FindDocInfoByRefKey(
		ctx context.Context,
		refKey types.DocRefKey,
	) (*DocInfo, error)

	// UpdateDocInfoStatusToRemoved updates the document status to removed.
	UpdateDocInfoStatusToRemoved(
		ctx context.Context,
		refKey types.DocRefKey,
	) error

	// CreateChangeInfos stores the given changes then updates the given docInfo.
	CreateChangeInfos(
		ctx context.Context,
		projectID types.ID,
		docInfo *DocInfo,
		initialServerSeq int64,
		changes []*change.Change,
		isRemoved bool,
	) error

	// PurgeStaleChanges delete changes before the smallest in `syncedseqs` to
	// save storage.
	PurgeStaleChanges(
		ctx context.Context,
		docRefKey types.DocRefKey,
	) error

	// FindLatestChangeInfoByActor returns the latest change created by given actorID.
	FindLatestChangeInfoByActor(
		ctx context.Context,
		docRefKey types.DocRefKey,
		actorID types.ID,
		serverSeq int64,
	) (*ChangeInfo, error)

	// FindChangesBetweenServerSeqs returns the changes between two server sequences.
	FindChangesBetweenServerSeqs(
		ctx context.Context,
		docRefKey types.DocRefKey,
		from int64,
		to int64,
	) ([]*change.Change, error)

	// FindChangeInfosBetweenServerSeqs returns the changeInfos between two server sequences.
	FindChangeInfosBetweenServerSeqs(
		ctx context.Context,
		docRefKey types.DocRefKey,
		from int64,
		to int64,
	) ([]*ChangeInfo, error)

	// CreateSnapshotInfo stores the snapshot of the given document.
	CreateSnapshotInfo(
		ctx context.Context,
		docRefKey types.DocRefKey,
		doc *document.InternalDocument,
	) error

	// FindSnapshotInfoByRefKey returns the snapshot by the given refKey.
	FindSnapshotInfoByRefKey(
		ctx context.Context,
		refKey types.SnapshotRefKey,
	) (*SnapshotInfo, error)

	// FindClosestSnapshotInfo finds the closest snapshot info in a given serverSeq.
	FindClosestSnapshotInfo(
		ctx context.Context,
		docRefKey types.DocRefKey,
		serverSeq int64,
		includeSnapshot bool,
	) (*SnapshotInfo, error)

	// FindMinSyncedSeqInfo finds the minimum synced sequence info.
	FindMinSyncedSeqInfo(
		ctx context.Context,
		docRefKey types.DocRefKey,
	) (*SyncedSeqInfo, error)

	// UpdateAndFindMinSyncedTicket updates the given serverSeq of the given client
	// and returns the min synced ticket.
	UpdateAndFindMinSyncedTicket(
		ctx context.Context,
		clientInfo *ClientInfo,
		docRefKey types.DocRefKey,
		serverSeq int64,
	) (*time.Ticket, error)

	// UpdateAndFindMinSyncedVersionVector updates the given serverSeq of the given client
	// and returns the SyncedVersionVector of the document.
	UpdateAndFindMinSyncedVersionVector(
		ctx context.Context,
		clientInfo *ClientInfo,
		docRefKey types.DocRefKey,
		versionVector time.VersionVector,
	) (time.VersionVector, error)

	// UpdateSyncedSeq updates the syncedSeq of the given client.
	UpdateSyncedSeq(
		ctx context.Context,
		clientInfo *ClientInfo,
		docRefKey types.DocRefKey,
		serverSeq int64,
	) error

	// UpdateVersionVector updates the syncedSeq of the given client.
	UpdateVersionVector(
		ctx context.Context,
		clientInfo *ClientInfo,
		docRefKey types.DocRefKey,
		versionVector time.VersionVector,
	) error

	// FindDocInfosByPaging returns the documentInfos of the given paging.
	FindDocInfosByPaging(
		ctx context.Context,
		projectID types.ID,
		paging types.Paging[types.ID],
	) ([]*DocInfo, error)

	// FindDocInfosByQuery returns the documentInfos which match the given query.
	FindDocInfosByQuery(
		ctx context.Context,
		projectID types.ID,
		query string,
		pageSize int,
	) (*types.SearchResult[*DocInfo], error)

	// IsDocumentAttached returns true if the document is attached to clients.
	IsDocumentAttached(
		ctx context.Context,
		docRefKey types.DocRefKey,
		excludeClientID types.ID,
	) (bool, error)
}

Database represents database which reads or saves Yorkie data.

type DocInfo 

type DocInfo struct {
	// ID is the unique ID of the document.
	ID types.ID `bson:"_id"`

	// ProjectID is the ID of the project that the document belongs to.
	ProjectID types.ID `bson:"project_id"`

	// Key is the key of the document.
	Key key.Key `bson:"key"`

	// ServerSeq is the sequence number of the last change of the document on the server.
	ServerSeq int64 `bson:"server_seq"`

	// Owner is the owner(ID of the client) of the document.
	Owner types.ID `bson:"owner"`

	// CreatedAt is the time when the document is created.
	CreatedAt time.Time `bson:"created_at"`

	// AccessedAt is the time when the document is accessed.
	AccessedAt time.Time `bson:"accessed_at"`

	// UpdatedAt is the time when the document is updated.
	UpdatedAt time.Time `bson:"updated_at"`

	// RemovedAt is the time when the document is removed.
	RemovedAt time.Time `bson:"removed_at"`
}

DocInfo is a structure representing information of the document.

func (*DocInfo) DeepCopy 

func (info *DocInfo) DeepCopy() *DocInfo

DeepCopy creates a deep copy of this DocInfo.

func (*DocInfo) IncreaseServerSeq 

func (info *DocInfo) IncreaseServerSeq() int64

IncreaseServerSeq increases server sequence of the document.

func (*DocInfo) IsRemoved added in v0.3.3 

func (info *DocInfo) IsRemoved() bool

IsRemoved returns true if the document is removed

func (*DocInfo) RefKey added in v0.4.14 

func (info *DocInfo) RefKey() types.DocRefKey

RefKey returns the refKey of the document.

type ProjectInfo 

type ProjectInfo struct {
	// ID is the unique ID of the project.
	ID types.ID `bson:"_id"`

	// Name is the name of this project.
	Name string `bson:"name"`

	// Owner is the owner of this project.
	Owner types.ID `bson:"owner"`

	// PublicKey is the API key of this project.
	PublicKey string `bson:"public_key"`

	// SecretKey is the secret key of this project.
	SecretKey string `bson:"secret_key"`

	// AuthWebhookURL is the url of the authorization webhook.
	AuthWebhookURL string `bson:"auth_webhook_url"`

	// AuthWebhookMethods is the methods that run the authorization webhook.
	AuthWebhookMethods []string `bson:"auth_webhook_methods"`

	// ClientDeactivateThreshold is the time after which clients in
	// specific project are considered deactivate for housekeeping.
	ClientDeactivateThreshold string `bson:"client_deactivate_threshold"`

	// CreatedAt is the time when the project was created.
	CreatedAt time.Time `bson:"created_at"`

	// UpdatedAt is the time when the project was updated.
	UpdatedAt time.Time `bson:"updated_at"`
}

ProjectInfo is a struct for project information.

func NewProjectInfo 

func NewProjectInfo(name string, owner types.ID, clientDeactivateThreshold string) *ProjectInfo

NewProjectInfo creates a new ProjectInfo of the given name.

func (*ProjectInfo) ClientDeactivateThresholdAsTimeDuration added in v0.3.1 

func (i *ProjectInfo) ClientDeactivateThresholdAsTimeDuration() (time.Duration, error)

ClientDeactivateThresholdAsTimeDuration converts ClientDeactivateThreshold string to time.Duration.

func (*ProjectInfo) DeepCopy 

func (i *ProjectInfo) DeepCopy() *ProjectInfo

DeepCopy returns a deep copy of the ProjectInfo.

func (*ProjectInfo) ToProject 

func (i *ProjectInfo) ToProject() *types.Project

ToProject converts the ProjectInfo to the Project.

func (*ProjectInfo) UpdateFields added in v0.2.8 

func (i *ProjectInfo) UpdateFields(fields *types.UpdatableProjectFields)

UpdateFields updates the fields.

type SnapshotInfo 

type SnapshotInfo struct {
	// ID is the unique ID of the snapshot.
	ID types.ID `bson:"_id"`

	// ProjectID is the ID of the project which the snapshot belongs to.
	ProjectID types.ID `bson:"project_id"`

	// DocID is the ID of the document which the snapshot belongs to.
	DocID types.ID `bson:"doc_id"`

	// ServerSeq is the sequence number of the server which the snapshot belongs to.
	ServerSeq int64 `bson:"server_seq"`

	// Lamport is the Lamport timestamp of the snapshot.
	Lamport int64 `bson:"lamport"`

	// VersionVector is the version vector of the snapshot.
	VersionVector time.VersionVector `bson:"version_vector"`

	// Snapshot is the snapshot data.
	Snapshot []byte `bson:"snapshot"`

	// CreatedAt is the time when the snapshot is created.
	CreatedAt gotime.Time `bson:"created_at"`
}

SnapshotInfo is a structure representing information of the snapshot.

func (*SnapshotInfo) DeepCopy added in v0.4.6 

func (i *SnapshotInfo) DeepCopy() *SnapshotInfo

DeepCopy returns a deep copy of the SnapshotInfo.

func (*SnapshotInfo) RefKey added in v0.4.14 

func (i *SnapshotInfo) RefKey() types.SnapshotRefKey

RefKey returns the refKey of the snapshot.

type SyncedSeqInfo 

type SyncedSeqInfo struct {
	ID        types.ID `bson:"_id"`
	ProjectID types.ID `bson:"project_id"`
	DocID     types.ID `bson:"doc_id"`
	ClientID  types.ID `bson:"client_id"`
	Lamport   int64    `bson:"lamport"`
	ActorID   types.ID `bson:"actor_id"`
	ServerSeq int64    `bson:"server_seq"`
}

SyncedSeqInfo is a structure representing information about the synchronized sequence for each client.

type UserInfo added in v0.2.14 

type UserInfo struct {
	ID             types.ID  `bson:"_id"`
	Username       string    `bson:"username"`
	HashedPassword string    `bson:"hashed_password"`
	CreatedAt      time.Time `bson:"created_at"`
}

UserInfo is a structure representing information of a user.

func NewUserInfo added in v0.2.14 

func NewUserInfo(username, hashedPassword string) *UserInfo

NewUserInfo creates a new UserInfo of the given username.

func (*UserInfo) DeepCopy added in v0.2.14 

func (i *UserInfo) DeepCopy() *UserInfo

DeepCopy returns a deep copy of the UserInfo

func (*UserInfo) ToUser added in v0.2.14 

func (i *UserInfo) ToUser() *types.User

ToUser converts the UserInfo to a User.

type VersionVectorInfo added in v0.5.3 

type VersionVectorInfo struct {
	ID            types.ID           `bson:"_id"`
	ProjectID     types.ID           `bson:"project_id"`
	DocID         types.ID           `bson:"doc_id"`
	ClientID      types.ID           `bson:"client_id"`
	VersionVector time.VersionVector `bson:"version_vector"`
}

VersionVectorInfo is a structure representing information about the version vector for each document and client.

Source Files

View all Source files

Directories

Path Synopsis
Package memory implements the database interface using in-memory database.
 Package memory implements the database interface using in-memory database.
Package mongo implements database interfaces using MongoDB.
 Package mongo implements database interfaces using MongoDB.
Package testcases contains testcases for database.
 Package testcases contains testcases for database.

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