positions

Documentation

Index

• func ConvertLegacyPositionsFile(legacyPath, newPath string, l log.Logger)
• func CursorKey(key string) string
• type Config
  • func (cfg *Config) RegisterFlags(flags *flag.FlagSet)
  • func (cfg *Config) RegisterFlagsWithPrefix(prefix string, f *flag.FlagSet)
• type Entry
• type File
• type LegacyFile
• type Positions
  • func New(logger log.Logger, cfg Config) (Positions, error)

Functions

func ConvertLegacyPositionsFile

func ConvertLegacyPositionsFile(legacyPath, newPath string, l log.Logger)

ConvertLegacyPositionsFile will convert the legacy positions file to the new format if: 1. There is no file at the newpath 2. There is a file at the legacy path and that it is valid yaml

func CursorKey

func CursorKey(key string) string

CursorKey returns a key that can be saved as a cursor that is never deleted.

Types

type Config

type Config struct {
	SyncPeriod        time.Duration `mapstructure:"sync_period" yaml:"sync_period"`
	PositionsFile     string        `mapstructure:"filename" yaml:"filename"`
	IgnoreInvalidYaml bool          `mapstructure:"ignore_invalid_yaml" yaml:"ignore_invalid_yaml"`
	ReadOnly          bool          `mapstructure:"-" yaml:"-"`
}

Config describes where to get position information from.

func (*Config) RegisterFlags

func (cfg *Config) RegisterFlags(flags *flag.FlagSet)

RegisterFlags register flags.

func (*Config) RegisterFlagsWithPrefix

func (cfg *Config) RegisterFlagsWithPrefix(prefix string, f *flag.FlagSet)

RegisterFlagsWithPrefix registers flags where every name is prefixed by prefix. If prefix is a non-empty string, prefix should end with a period.

type Entry

type Entry struct {
	Path   string `yaml:"path"`
	Labels string `yaml:"labels"`
}

Entry describes a positions file entry consisting of an absolute file path and the matching label set. An entry expects the string representation of a LabelSet or a Labels slice so that it can be utilized as a YAML key. The caller should make sure that the order and structure of the passed string representation is reproducible, and maintains the same format for both reading and writing from/to the positions file.

type File

type File struct {
	Positions map[Entry]string `yaml:"positions"`
}

File format for the positions data.

type LegacyFile

type LegacyFile struct {
	Positions map[string]string `yaml:"positions"`
}

LegacyFile is the copied struct for the static mode positions file.

type Positions

type Positions interface {
	// GetString returns how far we've through a file as a string.
	// JournalTarget writes a journal cursor to the positions file, while
	// FileTarget writes an integer offset. Use Get to read the integer
	// offset.
	GetString(path, labels string) string
	// Get returns how far we've read through a file. Returns an error
	// if the value stored for the file is not an integer.
	Get(path, labels string) (int64, error)
	// PutString records (asynchronously) how far we've read through a file.
	// Unlike Put, it records a string offset and is only useful for
	// JournalTargets which doesn't have integer offsets.
	PutString(path, labels string, pos string)
	// Put records (asynchronously) how far we've read through a file.
	Put(path, labels string, pos int64)
	// Remove removes the position tracking for a filepath
	Remove(path, labels string)
	// SyncPeriod returns how often the positions file gets resynced
	SyncPeriod() time.Duration
	// Stop the Position tracker.
	Stop()
}

func New

func New(logger log.Logger, cfg Config) (Positions, error)

New makes a new Positions.