acquire

Documentation

Overview

Copyright 2020 New Relic Corporation. All rights reserved. SPDX-License-Identifier: Apache-2.0 package acquire provides common functionality for the metrics acquisition

Index

• Variables
• func CalculateSafeDelta(current, previous uint64, elapsedSecs float64) float64
• func CombinedOutputTimeout(c *exec.Cmd, timeout time.Duration) ([]byte, error)
• func ReadLines(filename string) ([]string, error)
• func ReadLinesOffsetN(filename string, offset uint, n int) (ret []string, err error)
• func WaitTimeout(c *exec.Cmd, timeout time.Duration) error
• type Invoke
  • func (i Invoke) Command(name string, arg ...string) ([]byte, error)
• type Invoker

Variables

var (
	Timeout    = 3 * time.Second
	ErrTimeout = errors.New("Command timed out.")
)

Functions

func CalculateSafeDelta

func CalculateSafeDelta(current, previous uint64, elapsedSecs float64) float64

func CombinedOutputTimeout

func CombinedOutputTimeout(c *exec.Cmd, timeout time.Duration) ([]byte, error)

CombinedOutputTimeout runs the given command with the given timeout and returns the combined output of stdout and stderr. If the command times out, it attempts to kill the process.

func ReadLines

func ReadLines(filename string) ([]string, error)

ReadLines reads contents from a file and splits them by new lines. A convenience wrapper to ReadLinesOffsetN(filename, 0, -1).

func ReadLinesOffsetN

func ReadLinesOffsetN(filename string, offset uint, n int) (ret []string, err error)

ReadLines reads contents from file and splits them by new line. The offset tells at which line number to start. The count determines the number of lines to read (starting from offset):

n >= 0: at most n lines
n < 0: whole file

func WaitTimeout

func WaitTimeout(c *exec.Cmd, timeout time.Duration) error

WaitTimeout waits for the given command to finish with a timeout. It assumes the command has already been started. If the command times out, it attempts to kill the process.

Types

type Invoke

type Invoke struct{}

func (Invoke) Command

func (i Invoke) Command(name string, arg ...string) ([]byte, error)

type Invoker

type Invoker interface {
	Command(string, ...string) ([]byte, error)
}