horizon

package
v0.0.0-...-52243a4 Latest Latest
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 Go to latest Published: Oct 30, 2018 License: Apache-2.0 Imports: 62 Imported by: 0

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Index

Constants

This section is empty.

Variables

This section is empty.

Functions

func LoggerMiddleware 

func LoggerMiddleware(h http.Handler) http.Handler

LoggerMiddleware is the middleware that logs http requests and resposnes to the logging subsytem of horizon.

func RecoverMiddleware 

func RecoverMiddleware(h http.Handler) http.Handler

RecoverMiddleware helps the server recover from panics. It ensures that no request can fully bring down the horizon server, and it also logs the panics to the logging subsystem.

Types

type AccountShowAction 

type AccountShowAction struct {
	Action
	Address        string
	HistoryRecord  history.Account
	CoreData       []core.AccountData
	CoreRecord     core.Account
	CoreSigners    []core.Signer
	CoreTrustlines []core.Trustline
	Resource       horizon.Account
}

AccountShowAction renders a account summary found by its address.

func (AccountShowAction) Handle 

func (action AccountShowAction) Handle(w http.ResponseWriter, r *http.Request)

func (*AccountShowAction) JSON 

func (action *AccountShowAction) JSON()

JSON is a method for actions.JSON

func (*AccountShowAction) SSE 

func (action *AccountShowAction) SSE(stream sse.Stream)

SSE is a method for actions.SSE

type Action 

type Action struct {
	actions.Base
	App *App
	Log *log.Entry
	// contains filtered or unexported fields
}

Action is the "base type" for all actions in horizon. It provides structs that embed it with access to the App struct.

Additionally, this type is a trigger for go-codegen and causes the file at Action.tmpl to be instantiated for each struct that embeds Action.

func (*Action) CoreQ 

func (action *Action) CoreQ() *core.Q

CoreQ provides access to queries that access the stellar core database.

func (*Action) EnsureHistoryFreshness 

func (action *Action) EnsureHistoryFreshness()

EnsureHistoryFreshness halts processing and raises

func (*Action) FullURL 

func (action *Action) FullURL() *url.URL

FullURL returns the full url for this request

func (*Action) HistoryQ 

func (action *Action) HistoryQ() *history.Q

HistoryQ provides access to queries that access the history portion of horizon's database.

func (*Action) Prepare 

func (action *Action) Prepare(w http.ResponseWriter, r *http.Request)

Prepare sets the action's App field based upon the context

func (*Action) ValidateCursorAsDefault 

func (action *Action) ValidateCursorAsDefault()

ValidateCursorAsDefault ensures that the cursor parameter is valid in the way it is normally used, i.e. it is either the string "now" or a string of numerals that can be parsed as an int64.

func (*Action) ValidateCursorWithinHistory 

func (action *Action) ValidateCursorWithinHistory()

ValidateCursorWithinHistory compares the requested page of data against the ledger state of the history database. In the event that the cursor is guaranteed to return no results, we return a 410 GONE http response.

type App 

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

App represents the root of the state of a horizon instance.

func AppFromContext 

func AppFromContext(ctx context.Context) *App

AppFromContext returns the set app, if one has been set, from the provided context returns nil if no app has been set.

func NewApp 

func NewApp(config Config) (*App, error)

NewApp constructs an new App instance from the provided config.

func (*App) Close 

func (a *App) Close()

Close cancels the app and forces the closure of db connections

func (*App) Context 

func (a *App) Context(ctx context.Context) context.Context

Context create a context on from the App type.

func (*App) CoreQ 

func (a *App) CoreQ() *core.Q

CoreQ returns a helper object for performing sql queries aginst the stellar core database.

func (*App) CoreSession 

func (a *App) CoreSession(ctx context.Context) *db.Session

CoreSession returns a new session that loads data from the stellar core database. The returned session is bound to `ctx`.

func (*App) DeleteUnretainedHistory 

func (a *App) DeleteUnretainedHistory() error

DeleteUnretainedHistory forwards to the app's reaper. See `reap.DeleteUnretainedHistory` for details

func (*App) GetRateLimiter 

func (a *App) GetRateLimiter() *throttled.HTTPRateLimiter

GetRateLimiter returns the HTTPRateLimiter of the App.

func (*App) HistoryQ 

func (a *App) HistoryQ() *history.Q

HistoryQ returns a helper object for performing sql queries against the history portion of horizon's database.

func (*App) HorizonSession 

func (a *App) HorizonSession(ctx context.Context) *db.Session

HorizonSession returns a new session that loads data from the horizon database. The returned session is bound to `ctx`.

func (*App) IsHistoryStale 

func (a *App) IsHistoryStale() bool

IsHistoryStale returns true if the latest history ledger is more than `StaleThreshold` ledgers behind the latest core ledger

func (*App) Middleware 

func (app *App) Middleware(h http.Handler) http.Handler

Adds the "app" context into every request, so that subsequence middleware or handlers can retrieve a horizon.App instance

func (*App) Serve 

func (a *App) Serve()

Serve starts the horizon web server, binding it to a socket, setting up the shutdown signals.

func (*App) Tick 

func (a *App) Tick()

Tick triggers horizon to update all of it's background processes such as transaction submission, metrics, ingestion and reaping.

func (*App) UpdateLedgerState 

func (a *App) UpdateLedgerState()

UpdateLedgerState triggers a refresh of several metrics gauges, such as open db connections and ledger state

func (*App) UpdateMetrics 

func (a *App) UpdateMetrics()

UpdateMetrics triggers a refresh of several metrics gauges, such as open db connections and ledger state

func (*App) UpdateOperationFeeStatsState 

func (a *App) UpdateOperationFeeStatsState()

UpdateOperationFeeStatsState triggers a refresh of several operation fee metrics

func (*App) UpdateStellarCoreInfo 

func (a *App) UpdateStellarCoreInfo()

UpdateStellarCoreInfo updates the value of coreVersion and networkPassphrase from the Stellar core API.

type AssetsAction 

type AssetsAction struct {
	Action
	AssetCode    string
	AssetIssuer  string
	PagingParams db2.PageQuery
	Records      []assets.AssetStatsR
	Page         hal.Page
}

AssetsAction renders a page of Assets

func (AssetsAction) Handle 

func (action AssetsAction) Handle(w http.ResponseWriter, r *http.Request)

func (*AssetsAction) JSON 

func (action *AssetsAction) JSON()

JSON is a method for actions.JSON

type Config 

type Config struct {
	DatabaseURL            string
	StellarCoreDatabaseURL string
	StellarCoreURL         string
	Port                   int
	RateLimit              *throttled.RateQuota
	RateLimitRedisKey      string
	RedisURL               string
	FriendbotURL           *url.URL
	LogLevel               logrus.Level
	LogFile                string
	SentryDSN              string
	LogglyTag              string
	LogglyToken            string
	// Maximum length of the path returned by `/paths` endpoint.
	MaxPathLength uint
	// TLSCert is a path to a certificate file to use for horizon's TLS config
	TLSCert string
	// TLSKey is the path to a private key file to use for horizon's TLS config
	TLSKey string
	// Ingest is a boolean that indicates whether or not this horizon instance
	// should run the data ingestion subsystem.
	Ingest bool
	// HistoryRetentionCount represents the minimum number of ledgers worth of
	// history data to retain in the horizon database. For the purposes of
	// determining a "retention duration", each ledger roughly corresponds to 10
	// seconds of real time.
	HistoryRetentionCount uint
	// StaleThreshold represents the number of ledgers a history database may be
	// out-of-date by before horizon begins to respond with an error to history
	// requests.
	StaleThreshold uint
	// SkipCursorUpdate causes the ingestor to skip reporting the "last imported
	// ledger" state to stellar-core.
	SkipCursorUpdate bool
	// EnableAssetStats is a feature flag that determines whether to calculate
	// asset stats during the ingestion and expose `/assets` endpoint.
	// Enabling it has a negative impact on CPU when ingesting ledgers full of
	// many different assets related operations.
	EnableAssetStats bool
}

Config is the configuration for horizon. It get's populated by the app's main function and is provided to NewApp.

type DataShowAction 

type DataShowAction struct {
	Action
	Address string
	Key     string
	Data    core.AccountData
}

DataShowAction renders a account summary found by its address.

func (DataShowAction) Handle 

func (action DataShowAction) Handle(w http.ResponseWriter, r *http.Request)

func (*DataShowAction) JSON 

func (action *DataShowAction) JSON()

JSON is a method for actions.JSON

func (*DataShowAction) Raw 

func (action *DataShowAction) Raw()

Raw is a method for actions.Raw

func (*DataShowAction) SSE 

func (action *DataShowAction) SSE(stream sse.Stream)

SSE is a method for actions.SSE

type EffectIndexAction 

type EffectIndexAction struct {
	Action
	AccountFilter     string
	LedgerFilter      int32
	TransactionFilter string
	OperationFilter   int64

	PagingParams db2.PageQuery
	Records      []history.Effect
	Page         hal.Page
	Ledgers      history.LedgerCache
}

EffectIndexAction renders a page of effect resources, identified by a normal page query and optionally filtered by an account, ledger, transaction, or operation.

func (EffectIndexAction) Handle 

func (action EffectIndexAction) Handle(w http.ResponseWriter, r *http.Request)

func (*EffectIndexAction) JSON 

func (action *EffectIndexAction) JSON()

JSON is a method for actions.JSON

func (*EffectIndexAction) SSE 

func (action *EffectIndexAction) SSE(stream sse.Stream)

SSE is a method for actions.SSE

func (*EffectIndexAction) ValidateCursor 

func (action *EffectIndexAction) ValidateCursor()

ValidateCursor ensures that the provided cursor parameter is of the form OPERATIONID-INDEX (such as 1234-56) or is the special value "now" that represents the the cursor directly after the last closed ledger

type InitFn 

type InitFn func(*App)

InitFn is a function that contributes to the initialization of an App struct

type LedgerIndexAction 

type LedgerIndexAction struct {
	Action
	PagingParams db2.PageQuery
	Records      []history.Ledger
	Page         hal.Page
}

LedgerIndexAction renders a page of ledger resources, identified by a normal page query.

func (LedgerIndexAction) Handle 

func (action LedgerIndexAction) Handle(w http.ResponseWriter, r *http.Request)

func (*LedgerIndexAction) JSON 

func (action *LedgerIndexAction) JSON()

JSON is a method for actions.JSON

func (*LedgerIndexAction) SSE 

func (action *LedgerIndexAction) SSE(stream sse.Stream)

SSE is a method for actions.SSE

type LedgerShowAction 

type LedgerShowAction struct {
	Action
	Sequence int32
	Record   history.Ledger
}

LedgerShowAction renders a ledger found by its sequence number.

func (LedgerShowAction) Handle 

func (action LedgerShowAction) Handle(w http.ResponseWriter, r *http.Request)

func (*LedgerShowAction) JSON 

func (action *LedgerShowAction) JSON()

JSON is a method for actions.JSON

type MetricsAction 

type MetricsAction struct {
	Action
	Snapshot map[string]interface{}
}

MetricsAction collects and renders a snapshot from the metrics system that will inlude any previously registered metrics.

func (MetricsAction) Handle 

func (action MetricsAction) Handle(w http.ResponseWriter, r *http.Request)

func (*MetricsAction) JSON 

func (action *MetricsAction) JSON()

JSON is a method for actions.JSON

func (*MetricsAction) LoadSnapshot 

func (action *MetricsAction) LoadSnapshot()

LoadSnapshot populates action.Snapshot

Original code copied from github.com/rcrowley/go-metrics MarshalJSON

type NotFoundAction 

type NotFoundAction struct {
	Action
}

NotFoundAction renders a 404 response

func (NotFoundAction) Handle 

func (action NotFoundAction) Handle(w http.ResponseWriter, r *http.Request)

func (*NotFoundAction) JSON 

func (action *NotFoundAction) JSON()

JSON is a method for actions.JSON

type NotImplementedAction 

type NotImplementedAction struct {
	Action
}

NotImplementedAction renders a NotImplemented prblem

func (NotImplementedAction) Handle 

func (action NotImplementedAction) Handle(w http.ResponseWriter, r *http.Request)

func (*NotImplementedAction) JSON 

func (action *NotImplementedAction) JSON()

JSON is a method for actions.JSON

type OffersByAccountAction 

type OffersByAccountAction struct {
	Action
	Address   string
	PageQuery db2.PageQuery
	Records   []core.Offer
	Ledgers   history.LedgerCache
	Page      hal.Page
}

OffersByAccountAction renders a page of offer resources, for a given account. These offers are present in the ledger as of the latest validated ledger.

func (OffersByAccountAction) Handle 

func (action OffersByAccountAction) Handle(w http.ResponseWriter, r *http.Request)

func (*OffersByAccountAction) JSON 

func (action *OffersByAccountAction) JSON()

JSON is a method for actions.JSON

func (*OffersByAccountAction) SSE 

func (action *OffersByAccountAction) SSE(stream sse.Stream)

SSE is a method for actions.SSE

type OperationFeeStatsAction 

type OperationFeeStatsAction struct {
	Action
	Min         int64
	Mode        int64
	LastBaseFee int64
	LastLedger  int64
}

OperationFeeStatsAction renders a few useful statistics that describe the current state of operation fees on the network.

func (OperationFeeStatsAction) Handle 

func (action OperationFeeStatsAction) Handle(w http.ResponseWriter, r *http.Request)

func (*OperationFeeStatsAction) JSON 

func (action *OperationFeeStatsAction) JSON()

JSON is a method for actions.JSON

type OperationIndexAction 

type OperationIndexAction struct {
	Action
	LedgerFilter      int32
	AccountFilter     string
	TransactionFilter string
	PagingParams      db2.PageQuery
	Records           []history.Operation
	Ledgers           history.LedgerCache
	Page              hal.Page
}

OperationIndexAction renders a page of operations resources, identified by a normal page query and optionally filtered by an account, ledger, or transaction.

func (OperationIndexAction) Handle 

func (action OperationIndexAction) Handle(w http.ResponseWriter, r *http.Request)

func (*OperationIndexAction) JSON 

func (action *OperationIndexAction) JSON()

JSON is a method for actions.JSON

func (*OperationIndexAction) SSE 

func (action *OperationIndexAction) SSE(stream sse.Stream)

SSE is a method for actions.SSE

type OperationShowAction 

type OperationShowAction struct {
	Action
	ID       int64
	Record   history.Operation
	Ledger   history.Ledger
	Resource interface{}
}

OperationShowAction renders a ledger found by its sequence number.

func (OperationShowAction) Handle 

func (action OperationShowAction) Handle(w http.ResponseWriter, r *http.Request)

func (*OperationShowAction) JSON 

func (action *OperationShowAction) JSON()

JSON is a method for actions.JSON

type OrderBookShowAction 

type OrderBookShowAction struct {
	Action
	Selling  xdr.Asset
	Buying   xdr.Asset
	Record   core.OrderBookSummary
	Resource horizon.OrderBookSummary
	Limit    uint64
}

OrderBookShowAction renders a account summary found by its address.

func (OrderBookShowAction) Handle 

func (action OrderBookShowAction) Handle(w http.ResponseWriter, r *http.Request)

func (*OrderBookShowAction) JSON 

func (action *OrderBookShowAction) JSON()

JSON is a method for actions.JSON

func (*OrderBookShowAction) LoadQuery 

func (action *OrderBookShowAction) LoadQuery()

LoadQuery sets action.Query from the request params

func (*OrderBookShowAction) LoadRecord 

func (action *OrderBookShowAction) LoadRecord()

LoadRecord populates action.Record

func (*OrderBookShowAction) LoadResource 

func (action *OrderBookShowAction) LoadResource()

LoadResource populates action.Record

func (*OrderBookShowAction) SSE 

func (action *OrderBookShowAction) SSE(stream sse.Stream)

SSE is a method for actions.SSE

type PathIndexAction 

type PathIndexAction struct {
	Action
	Query   paths.Query
	Records []paths.Path
	Page    hal.BasePage
}

PathIndexAction provides path finding

func (PathIndexAction) Handle 

func (action PathIndexAction) Handle(w http.ResponseWriter, r *http.Request)

func (*PathIndexAction) JSON 

func (action *PathIndexAction) JSON()

JSON implements actions.JSON

type PaymentsIndexAction 

type PaymentsIndexAction struct {
	Action
	LedgerFilter      int32
	AccountFilter     string
	TransactionFilter string
	PagingParams      db2.PageQuery
	Records           []history.Operation
	Ledgers           history.LedgerCache
	Page              hal.Page
}

PaymentsIndexAction returns a paged slice of payments based upon the provided filters

func (PaymentsIndexAction) Handle 

func (action PaymentsIndexAction) Handle(w http.ResponseWriter, r *http.Request)

func (*PaymentsIndexAction) JSON 

func (action *PaymentsIndexAction) JSON()

JSON is a method for actions.JSON

func (*PaymentsIndexAction) SSE 

func (action *PaymentsIndexAction) SSE(stream sse.Stream)

SSE is a method for actions.SSE

type RateLimitExceededAction 

type RateLimitExceededAction struct {
	Action
	App *App
}

RateLimitExceededAction renders a 429 response

func (RateLimitExceededAction) Handle 

func (action RateLimitExceededAction) Handle(w http.ResponseWriter, r *http.Request)

func (RateLimitExceededAction) ServeHTTP 

func (action RateLimitExceededAction) ServeHTTP(w http.ResponseWriter, r *http.Request)

type RootAction 

type RootAction struct {
	Action
}

RootAction provides a summary of the horizon instance and links to various useful endpoints

func (RootAction) Handle 

func (action RootAction) Handle(w http.ResponseWriter, r *http.Request)

func (*RootAction) JSON 

func (action *RootAction) JSON()

JSON renders the json response for RootAction

type TradeAggregateIndexAction 

type TradeAggregateIndexAction struct {
	Action
	BaseAssetFilter    xdr.Asset
	CounterAssetFilter xdr.Asset
	StartTimeFilter    time.Millis
	EndTimeFilter      time.Millis
	OffsetFilter       int64
	ResolutionFilter   int64
	PagingParams       db2.PageQuery
	Records            []history.TradeAggregation
	Page               hal.Page
}

func (TradeAggregateIndexAction) Handle 

func (action TradeAggregateIndexAction) Handle(w http.ResponseWriter, r *http.Request)

func (*TradeAggregateIndexAction) JSON 

func (action *TradeAggregateIndexAction) JSON()

JSON is a method for actions.JSON

type TradeIndexAction 

type TradeIndexAction struct {
	Action
	BaseAssetFilter       xdr.Asset
	HasBaseAssetFilter    bool
	CounterAssetFilter    xdr.Asset
	HasCounterAssetFilter bool
	OfferFilter           int64
	AccountFilter         string
	PagingParams          db2.PageQuery
	Records               []history.Trade
	Page                  hal.Page
}

func (TradeIndexAction) Handle 

func (action TradeIndexAction) Handle(w http.ResponseWriter, r *http.Request)

func (*TradeIndexAction) JSON 

func (action *TradeIndexAction) JSON()

JSON is a method for actions.JSON

func (*TradeIndexAction) SSE 

func (action *TradeIndexAction) SSE(stream sse.Stream)

SSE is a method for actions.SSE

type TransactionCreateAction 

type TransactionCreateAction struct {
	Action
	TX       string
	Result   txsub.Result
	Resource horizon.TransactionSuccess
}

TransactionCreateAction submits a transaction to the stellar-core network on behalf of the requesting client.

func (TransactionCreateAction) Handle 

func (action TransactionCreateAction) Handle(w http.ResponseWriter, r *http.Request)

func (*TransactionCreateAction) JSON 

func (action *TransactionCreateAction) JSON()

JSON format action handler

type TransactionIndexAction 

type TransactionIndexAction struct {
	Action
	LedgerFilter  int32
	AccountFilter string
	PagingParams  db2.PageQuery
	Records       []history.Transaction
	Page          hal.Page
}

TransactionIndexAction renders a page of ledger resources, identified by a normal page query.

func (TransactionIndexAction) Handle 

func (action TransactionIndexAction) Handle(w http.ResponseWriter, r *http.Request)

func (*TransactionIndexAction) JSON 

func (action *TransactionIndexAction) JSON()

JSON is a method for actions.JSON

func (*TransactionIndexAction) SSE 

func (action *TransactionIndexAction) SSE(stream sse.Stream)

SSE is a method for actions.SSE

type TransactionShowAction 

type TransactionShowAction struct {
	Action
	Hash     string
	Record   history.Transaction
	Resource horizon.Transaction
}

TransactionShowAction renders a ledger found by its sequence number.

func (TransactionShowAction) Handle 

func (action TransactionShowAction) Handle(w http.ResponseWriter, r *http.Request)

func (*TransactionShowAction) JSON 

func (action *TransactionShowAction) JSON()

JSON is a method for actions.JSON

type VaryByRemoteIP 

type VaryByRemoteIP struct{}

func (VaryByRemoteIP) Key 

func (v VaryByRemoteIP) Key(r *http.Request) string

type Web 

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

Web contains the http server related fields for horizon: the router, rate limiter, etc.

func (*Web) RateLimitMiddleware 

func (web *Web) RateLimitMiddleware(next http.Handler) http.Handler

Source Files

View all Source files

Directories

Path Synopsis
Package actions provides the infrastructure for defining and executing actions (code that is triggered in response to an client request) on horizon.
 Package actions provides the infrastructure for defining and executing actions (code that is triggered in response to an client request) on horizon.
Package assets is a simple helper package to help convert to/from xdr.AssetType values
 Package assets is a simple helper package to help convert to/from xdr.AssetType values
Package codes is a helper package to help convert to transaction and operation result codes to strings used in horizon.
 Package codes is a helper package to help convert to transaction and operation result codes to strings used in horizon.
db2
Package db2 is the replacement for db.
 Package db2 is the replacement for db.
assets
core
Package core contains database record definitions useable for reading rows from a Stellar Core db
 Package core contains database record definitions useable for reading rows from a Stellar Core db
history
Package history contains database record definitions useable for reading rows from a the history portion of horizon's database
 Package history contains database record definitions useable for reading rows from a the history portion of horizon's database
schema
sqx
Package sqx contains utilities and extensions for the squirrel package which is used by horizon to generate sql statements.
 Package sqx contains utilities and extensions for the squirrel package which is used by horizon to generate sql statements.
Package ingest contains the ingestion system for horizon.
 Package ingest contains the ingestion system for horizon.
participants
Package participants contains functions to derive a set of "participant" addresses for various data structures in the Stellar network's ledger.
 Package participants contains functions to derive a set of "participant" addresses for various data structures in the Stellar network's ledger.
Package ledger provides useful utilities concerning ledgers within stellar, specifically as a central location to store a cached snapshot of the state of both horizon's and stellar-core's views of the ledger.
 Package ledger provides useful utilities concerning ledgers within stellar, specifically as a central location to store a cached snapshot of the state of both horizon's and stellar-core's views of the ledger.
Package operationfeestats provides useful utilities concerning operation fee stats within stellar,specifically as a central location to store a cached snapshot of the state of network per operation fees and surge pricing.
 Package operationfeestats provides useful utilities concerning operation fee stats within stellar,specifically as a central location to store a cached snapshot of the state of network per operation fees and surge pricing.
Package paths provides utilities and facilities for payment paths as needed by horizon.
 Package paths provides utilities and facilities for payment paths as needed by horizon.
Package reap contains the history reaping subsystem for horizon.
 Package reap contains the history reaping subsystem for horizon.
problem
sse
This package contains the Server Sent Events implementation used by horizon.
 This package contains the Server Sent Events implementation used by horizon.
Package simplepath provides an implementation of paths.
 Package simplepath provides an implementation of paths.
Package test contains simple test helpers that should not have any dependencies on horizon's packages.
 Package test contains simple test helpers that should not have any dependencies on horizon's packages.
db
Package db provides helpers to connect to test databases.
 Package db provides helpers to connect to test databases.
scenarios
trades
Common infrastructure for testing Trades
 Common infrastructure for testing Trades
Package txsub provides the machinery that horizon uses to submit transactions to the stellar network and track their progress.
 Package txsub provides the machinery that horizon uses to submit transactions to the stellar network and track their progress.
results/db
Package results provides an implementation of the txsub.ResultProvider interface backed using the SQL databases used by both stellar core and horizon
 Package results provides an implementation of the txsub.ResultProvider interface backed using the SQL databases used by both stellar core and horizon
sequence
Package sequence providers helpers to manage sequence numbers on behalf of horizon clients.
 Package sequence providers helpers to manage sequence numbers on behalf of horizon clients.
Package utf8 contains utilities for working with utf8 data.
 Package utf8 contains utilities for working with utf8 data.

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