expvar

Documentation

Overview

Package expvar contains logic to read from an expvar provide. The data comes in JSON format. The GC and memory related information will be changed to better presented to the data recorders. Bytes will be turned into megabytes, gc lists will be truncated to remove zero values.

Index

• type Config
  • func FromViper(v unmarshaller, log internal.FieldLogger, name, key string) (*Config, error)
  • func NewConfig(log internal.FieldLogger, name, typeName string, endpoint, routepath string, ...) (*Config, error)
  • func (c *Config) Backoff() int
  • func (c *Config) Endpoint() string
  • func (c *Config) Interval() time.Duration
  • func (c *Config) Logger() internal.FieldLogger
  • func (c *Config) Name() string
  • func (c *Config) NewInstance() (reader.DataReader, error)
  • func (c *Config) RoutePath() string
  • func (c *Config) Timeout() time.Duration
  • func (c *Config) TypeName() string
• type Reader
  • func New(options ...func(reader.Constructor) error) (*Reader, error)
  • func (r *Reader) Backoff() int
  • func (r *Reader) Endpoint() string
  • func (r *Reader) Interval() time.Duration
  • func (r *Reader) Logger() internal.FieldLogger
  • func (r *Reader) Mapper() datatype.Mapper
  • func (r *Reader) Name() string
  • func (r *Reader) Ping() error
  • func (r *Reader) Read(job *token.Context) (*reader.Result, error)
  • func (r *Reader) SetBackoff(backoff int)
  • func (r *Reader) SetEndpoint(endpoint string)
  • func (r *Reader) SetInterval(interval time.Duration)
  • func (r *Reader) SetLogger(log internal.FieldLogger)
  • func (r *Reader) SetMapper(mapper datatype.Mapper)
  • func (r *Reader) SetName(name string)
  • func (r *Reader) SetTimeout(timeout time.Duration)
  • func (r *Reader) SetTypeName(typeName string)
  • func (r *Reader) Timeout() time.Duration
  • func (r *Reader) TypeName() string

Types

type Config

type Config struct {
	EXPTypeName  string `mapstructure:"type_name"`
	EXPEndpoint  string `mapstructure:"endpoint"`
	EXPRoutePath string `mapstructure:"routepath"`
	EXPInterval  string `mapstructure:"interval"`
	EXPTimeout   string `mapstructure:"timeout"`
	EXPBackoff   int    `mapstructure:"backoff"`
	MapFile      string `mapstructure:"map_file"`
	// contains filtered or unexported fields
}

Config holds the necessary configuration for setting up an expvar reader endpoint. If MapFile is provided, the data will be mapped, otherwise it uses the DefaultMapper.

func FromViper

func FromViper(v unmarshaller, log internal.FieldLogger, name, key string) (*Config, error)

FromViper constructs the necessary configuration for bootstrapping the expvar reader.

func NewConfig

func NewConfig(log internal.FieldLogger, name, typeName string, endpoint, routepath string, interval, timeout time.Duration, backoff int, mapFile string) (*Config, error)

NewConfig returns an instance of the expvar reader

func (*Config) Backoff

func (c *Config) Backoff() int

Backoff returns backoff

func (*Config) Endpoint

func (c *Config) Endpoint() string

Endpoint returns endpoint

func (*Config) Interval

func (c *Config) Interval() time.Duration

Interval returns interval

func (*Config) Logger

func (c *Config) Logger() internal.FieldLogger

Logger returns logger

func (*Config) Name

func (c *Config) Name() string

Name returns name

func (*Config) NewInstance

func (c *Config) NewInstance() (reader.DataReader, error)

NewInstance returns an instance of the expvar reader.

func (*Config) RoutePath

func (c *Config) RoutePath() string

RoutePath returns routepath

func (*Config) Timeout

func (c *Config) Timeout() time.Duration

Timeout returns timeout

func (*Config) TypeName

func (c *Config) TypeName() string

TypeName returns type name

type Reader

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

Reader can read from any application that exposes expvar information. It implements DataReader interface.

func New

func New(options ...func(reader.Constructor) error) (*Reader, error)

New generates the Reader based on the provided options It returns and error on the following occasions:

Condition            |  Error
---------------------|-------------
name == ""           | ErrEmptyName
endpoint == ""       | ErrEmptyEndpoint
Invalid endpoint     | ErrInvalidEndpoint
typeName == ""       | ErrEmptyTypeName
backoff < 5          | ErrLowBackoffValue

func (*Reader) Backoff

func (r *Reader) Backoff() int

Backoff returns the backoff

func (*Reader) Endpoint

func (r *Reader) Endpoint() string

Endpoint returns the endpoint

func (*Reader) Interval

func (r *Reader) Interval() time.Duration

Interval returns the interval

func (*Reader) Logger

func (r *Reader) Logger() internal.FieldLogger

Logger returns the log

func (*Reader) Mapper

func (r *Reader) Mapper() datatype.Mapper

Mapper returns the mapper object

func (*Reader) Name

func (r *Reader) Name() string

Name shows the name identifier for this reader

func (*Reader) Ping

func (r *Reader) Ping() error

Ping pings the endpoint and return nil if was successful. It returns an ErrEndpointNotAvailable if the endpoint id unavailable.

func (*Reader) Read

func (r *Reader) Read(job *token.Context) (*reader.Result, error)

Read begins reading from the target. It returns an error back to the engine if it can't read from metrics provider, Ping() is not called or the endpoint has been unresponsive too many times.

func (*Reader) SetBackoff

func (r *Reader) SetBackoff(backoff int)

SetBackoff sets the backoff of the reader

func (*Reader) SetEndpoint

func (r *Reader) SetEndpoint(endpoint string)

SetEndpoint sets the endpoint of the reader

func (*Reader) SetInterval

func (r *Reader) SetInterval(interval time.Duration)

SetInterval sets the interval of the reader

func (*Reader) SetLogger

func (r *Reader) SetLogger(log internal.FieldLogger)

SetLogger sets the log of the reader

func (*Reader) SetMapper

func (r *Reader) SetMapper(mapper datatype.Mapper)

SetMapper sets the mapper of the reader

func (*Reader) SetName

func (r *Reader) SetName(name string)

SetName sets the name of the reader

func (*Reader) SetTimeout

func (r *Reader) SetTimeout(timeout time.Duration)

SetTimeout sets the timeout of the reader

func (*Reader) SetTypeName

func (r *Reader) SetTypeName(typeName string)

SetTypeName sets the type name of the reader

func (*Reader) Timeout

func (r *Reader) Timeout() time.Duration

Timeout returns the time-out

func (*Reader) TypeName

func (r *Reader) TypeName() string

TypeName shows the typeName the recorder should record as