horizon

Documentation

Index

• Constants
• func ApplyFlags(config *Config, flags support.ConfigOptions, options ApplyOptions) error
• type App
  • func NewApp(config Config) (*App, error)
  • func NewAppFromFlags(config *Config, flags support.ConfigOptions) (*App, error)
  • func (a *App) Close()
  • func (a *App) CloseDB()
  • func (a *App) Config() Config
  • func (a *App) DeleteUnretainedHistory(ctx context.Context) error
  • func (a *App) GetCoreState() corestate.State
  • func (a *App) HistoryQ() *history.Q
  • func (a *App) HorizonSession() db.SessionInterface
  • func (a *App) Paths() paths.Finder
  • func (a *App) Serve() error
  • func (a *App) Tick(ctx context.Context) error
  • func (a *App) UpdateCoreLedgerState(ctx context.Context)
  • func (a *App) UpdateFeeStatsState(ctx context.Context)
  • func (a *App) UpdateHorizonLedgerState(ctx context.Context)
  • func (a *App) UpdateStellarCoreInfo(ctx context.Context) error
• type ApplyOptions
• type Config
  • func Flags() (*Config, support.ConfigOptions)

Constants

const (
	// DatabaseURLFlagName is the command line flag for configuring the Horizon postgres URL
	DatabaseURLFlagName = "db-url"
	// IngestFlagName is the command line flag for enabling ingestion on the Horizon instance
	IngestFlagName = "ingest"
	// StellarCoreDBURLFlagName is the command line flag for configuring the postgres Stellar Core URL
	StellarCoreDBURLFlagName = "stellar-core-db-url"
	// StellarCoreURLFlagName is the command line flag for configuring the URL fore Stellar Core HTTP endpoint
	StellarCoreURLFlagName = "stellar-core-url"
	// StellarCoreBinaryPathName is the command line flag for configuring the path to the stellar core binary
	StellarCoreBinaryPathName = "stellar-core-binary-path"

	// CaptiveCoreConfigPathName is the command line flag for configuring the path to the captive core configuration file
	CaptiveCoreConfigPathName = "captive-core-config-path"
	// captive-core-use-db is the command line flag for enabling captive core runtime to use an external db url connection rather than RAM for ledger states
	CaptiveCoreConfigUseDB = "captive-core-use-db"
)

Functions

func ApplyFlags

func ApplyFlags(config *Config, flags support.ConfigOptions, options ApplyOptions) error

ApplyFlags applies the command line flags on the given Config instance

Types

type App

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

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

func NewApp

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

NewApp constructs an new App instance from the provided config.

func NewAppFromFlags

func NewAppFromFlags(config *Config, flags support.ConfigOptions) (*App, error)

NewAppFromFlags constructs a new Horizon App from the given command line flags

func (*App) Close

func (a *App) Close()

Close cancels the app. It does not close DB connections - use App.CloseDB().

func (*App) CloseDB

func (a *App) CloseDB()

CloseDB closes DB connections. When using during web server shut down make sure all requests are first properly finished to avoid "sql: database is closed" errors.

func (*App) Config

func (a *App) Config() Config

func (*App) DeleteUnretainedHistory

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

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

func (*App) GetCoreState

func (a *App) GetCoreState() corestate.State

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() db.SessionInterface

HorizonSession returns a new session that loads data from the horizon database.

func (*App) Paths

func (a *App) Paths() paths.Finder

Paths returns the paths.Finder instance used by horizon

func (*App) Serve

func (a *App) Serve() error

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

func (*App) Tick

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

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

func (*App) UpdateCoreLedgerState

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

UpdateCoreLedgerState triggers a refresh of Stellar-Core ledger state. This is done separately from Horizon ledger state update to prevent issues in case Stellar-Core query timeout.

func (*App) UpdateFeeStatsState

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

UpdateFeeStatsState triggers a refresh of several operation fee metrics.

func (*App) UpdateHorizonLedgerState

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

UpdateHorizonLedgerState triggers a refresh of Horizon ledger state. This is done separately from Core ledger state update to prevent issues in case Stellar-Core query timeout.

func (*App) UpdateStellarCoreInfo

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

UpdateStellarCoreInfo updates the value of CoreVersion, CurrentProtocolVersion, and CoreSupportedProtocolVersion from the Stellar core API.

Warning: This method should only return an error if it is fatal. See usage in `App.Tick`

type ApplyOptions

type ApplyOptions struct {
	AlwaysIngest             bool
	RequireCaptiveCoreConfig bool
}

type Config

type Config struct {
	DatabaseURL        string
	RoDatabaseURL      string
	HistoryArchiveURLs []string
	Port               uint
	AdminPort          uint

	EnableCaptiveCoreIngestion  bool
	EnableIngestionFiltering    bool
	UsingDefaultPubnetConfig    bool
	CaptiveCoreBinaryPath       string
	RemoteCaptiveCoreURL        string
	CaptiveCoreConfigPath       string
	CaptiveCoreTomlParams       ledgerbackend.CaptiveCoreTomlParams
	CaptiveCoreToml             *ledgerbackend.CaptiveCoreToml
	CaptiveCoreStoragePath      string
	CaptiveCoreReuseStoragePath bool
	CaptiveCoreConfigUseDB      bool

	StellarCoreDatabaseURL string
	StellarCoreURL         string

	// MaxDBConnections has a priority over all 4 values below.
	MaxDBConnections            int
	HorizonDBMaxOpenConnections int
	HorizonDBMaxIdleConnections int

	SSEUpdateFrequency time.Duration
	ConnectionTimeout  time.Duration
	RateQuota          *throttled.RateQuota
	FriendbotURL       *url.URL
	LogLevel           logrus.Level
	LogFile            string

	// MaxPathLength is the maximum length of the path returned by `/paths` endpoint.
	MaxPathLength uint
	// MaxAssetsPerPathRequest is the maximum number of assets considered for `/paths/strict-send` and `/paths/strict-receive`
	MaxAssetsPerPathRequest int
	// DisablePoolPathFinding configures horizon to run path finding without including liquidity pools
	// in the path finding search.
	DisablePoolPathFinding bool
	// DisablePathFinding configures horizon without the path finding endpoint.
	DisablePathFinding bool
	// MaxPathFindingRequests is the maximum number of path finding requests horizon will allow
	// in a 1-second period. A value of 0 disables the limit.
	MaxPathFindingRequests uint

	NetworkPassphrase string
	SentryDSN         string
	LogglyToken       string
	LogglyTag         string
	// 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 toggles whether this horizon instance should run the data ingestion subsystem.
	Ingest bool
	// CursorName is the cursor used for ingesting from stellar-core.
	// Setting multiple cursors in different Horizon instances allows multiple
	// Horizons to ingest from the same stellar-core instance without cursor
	// collisions.
	CursorName string
	// 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
	// IngestDisableStateVerification disables state verification
	// `System.verifyState()` when set to `true`.
	IngestDisableStateVerification bool
	// IngestEnableExtendedLogLedgerStats enables extended ledger stats in
	// logging.
	IngestEnableExtendedLogLedgerStats bool
	// ApplyMigrations will apply pending migrations to the horizon database
	// before starting the horizon service
	ApplyMigrations bool
	// CheckpointFrequency establishes how many ledgers exist between checkpoints
	CheckpointFrequency uint32
	// BehindCloudflare determines if Horizon instance is behind Cloudflare. In
	// such case http.Request.RemoteAddr will be replaced with Cloudflare header.
	BehindCloudflare bool
	// BehindAWSLoadBalancer determines if Horizon instance is behind AWS load
	// balances like ELB or ALB. In such case http.Request.RemoteAddr will be
	// replaced with the last IP in X-Forwarded-For header.
	BehindAWSLoadBalancer bool
	// RoundingSlippageFilter excludes trades from /trade_aggregations with rounding slippage >x bps
	RoundingSlippageFilter int
}

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

func Flags

func Flags() (*Config, support.ConfigOptions)

Flags returns a Config instance and a list of commandline flags which modify the Config instance