limits

Documentation

Overview

Package limits contains paths to enforce read query limits.

Index

• func IsQueryLimitExceededError(err error) bool
• func NewQueryLimitExceededError(msg string) error
• type Key
• type LookbackLimit
• type LookbackLimitOptions
  • func DefaultLookbackLimitOptions() LookbackLimitOptions
• type Options
  • func NewOptions() Options
• type QueryLimits
  • func NewQueryLimits(options Options) (QueryLimits, error)
  • func NoOpQueryLimits() QueryLimits
• type SourceLogger
• type SourceLoggerBuilder

Functions

func IsQueryLimitExceededError

func IsQueryLimitExceededError(err error) bool

IsQueryLimitExceededError returns true if the error is a query limits exceeded error.

func NewQueryLimitExceededError

func NewQueryLimitExceededError(msg string) error

NewQueryLimitExceededError creates a query limit exceeded error.

Types

type Key

type Key string

Key is a specific string type for context setting.

const SourceContextKey Key = "source"

SourceContextKey is the key for setting and retrieving source from context.

type LookbackLimit

type LookbackLimit interface {
	// Inc increments the recent value for the limit.
	Inc(new int, source []byte) error
}

LookbackLimit provides an interface for a specific query limit.

type LookbackLimitOptions

type LookbackLimitOptions struct {
	// Limit past which errors will be returned.
	Limit int64
	// Lookback is the period over which the limit is enforced.
	Lookback time.Duration
}

LookbackLimitOptions holds options for a lookback limit to be enforced.

func DefaultLookbackLimitOptions

func DefaultLookbackLimitOptions() LookbackLimitOptions

DefaultLookbackLimitOptions returns a new query limits manager.

type Options

type Options interface {
	// Validate validates the options.
	Validate() error

	// SetInstrumentOptions sets the instrument options.
	SetInstrumentOptions(value instrument.Options) Options

	// InstrumentOptions returns the instrument options.
	InstrumentOptions() instrument.Options

	// SetDocsLimitOpts sets the doc limit options.
	SetDocsLimitOpts(value LookbackLimitOptions) Options

	// DocsLimitOpts returns the doc limit options.
	DocsLimitOpts() LookbackLimitOptions

	// SetBytesReadLimitOpts sets the byte read limit options.
	SetBytesReadLimitOpts(value LookbackLimitOptions) Options

	// BytesReadLimitOpts returns the byte read limit options.
	BytesReadLimitOpts() LookbackLimitOptions

	// SetSourceLoggerBuilder sets the source logger.
	SetSourceLoggerBuilder(value SourceLoggerBuilder) Options

	// SourceLogger sets the source logger.
	SourceLoggerBuilder() SourceLoggerBuilder
}

Options is a set of limit options.

func NewOptions

func NewOptions() Options

NewOptions creates limit options with default values.

type QueryLimits

type QueryLimits interface {
	// DocsLimit limits queries by a global concurrent count of index docs matched.
	DocsLimit() LookbackLimit
	// BytesReadLimit limits queries by a global concurrent count of bytes read from disk.
	BytesReadLimit() LookbackLimit

	// AnyExceeded returns an error if any of the query limits are exceeded.
	AnyExceeded() error
	// Start begins background resetting of the query limits.
	Start()
	// Stop end background resetting of the query limits.
	Stop()
}

QueryLimits provides an interface for managing query limits.

func NewQueryLimits

func NewQueryLimits(
	options Options,

) (QueryLimits, error)

NewQueryLimits returns a new query limits manager.

func NoOpQueryLimits

func NoOpQueryLimits() QueryLimits

NoOpQueryLimits returns inactive query limits.

type SourceLogger

type SourceLogger interface {
	// LogSourceValue attributes values that exceed a given size to the source.
	LogSourceValue(val int64, source []byte)
}

SourceLogger attributes limit values to a source.

type SourceLoggerBuilder

type SourceLoggerBuilder interface {
	// NewSourceLogger builds a source logger.
	NewSourceLogger(name string, opts instrument.Options) SourceLogger
}

SourceLoggerBuilder builds a SourceLogger given instrument options.