config

Documentation

Overview

Package config provides types and functions to collect, validate and apply user-provided settings.

Index

• Constants
• Variables
• func Branding(msg string) func() string
• func Usage(flagSet *flag.FlagSet, w io.Writer) func()
• func Version() string
• type AppType
• type Config
  • func New(appType AppType) (*Config, error)
  • func (c *Config) Help() string
• type InspectorSettings

Constants

const (
	HelpFlagLong             string = "help"
	HelpFlagShort            string = "h"
	VersionFlagLong          string = "version"
	BrandingFlag             string = "branding"
	TimeoutFlagLong          string = "timeout"
	TimeoutFlagShort         string = "t"
	LogLevelFlagLong         string = "log-level"
	LogLevelFlagShort        string = "ll"
	ShowAllProcessesFlagLong string = "show-all"
)

Flag names for consistent references. Exported so that they're available from tests.

const (

	// LogLevelDisabled maps to zerolog.Disabled logging level
	LogLevelDisabled string = "disabled"

	// LogLevelPanic maps to zerolog.PanicLevel logging level
	LogLevelPanic string = "panic"

	// LogLevelFatal maps to zerolog.FatalLevel logging level
	LogLevelFatal string = "fatal"

	// LogLevelError maps to zerolog.ErrorLevel logging level
	LogLevelError string = "error"

	// LogLevelWarn maps to zerolog.WarnLevel logging level
	LogLevelWarn string = "warn"

	// LogLevelInfo maps to zerolog.InfoLevel logging level
	LogLevelInfo string = "info"

	// LogLevelDebug maps to zerolog.DebugLevel logging level
	LogLevelDebug string = "debug"

	// LogLevelTrace maps to zerolog.TraceLevel logging level
	LogLevelTrace string = "trace"
)

const ExitCodeCatchall int = 1

ExitCodeCatchall indicates a general or miscellaneous error has occurred. This exit code is not directly used by monitoring plugins in this project. See https://tldp.org/LDP/abs/html/exitcodes.html for additional details.

Variables

var (
	// ErrVersionRequested indicates that the user requested application version
	// information.
	ErrVersionRequested = errors.New("version information requested")

	// ErrHelpRequested indicates that the user requested application
	// help/usage information.
	ErrHelpRequested = errors.New("help/usage information requested")

	// ErrUnsupportedOption indicates that an unsupported option was specified.
	ErrUnsupportedOption = errors.New("unsupported option")

	// ErrConfigNotInitialized indicates that the configuration is not in a
	// usable state and application execution can not successfully proceed.
	ErrConfigNotInitialized = errors.New("configuration not initialized")
)

Functions

func Branding

func Branding(msg string) func() string

Branding accepts a message and returns a function that concatenates that message with version information. This function is intended to be called as a final step before application exit after any other output has already been emitted.

func Usage

func Usage(flagSet *flag.FlagSet, w io.Writer) func()

Usage is a custom override for the default Help text provided by the flag package. Here we prepend some additional metadata to the existing output.

func Version

func Version() string

Version emits application name, version and repo location.

Types

type AppType

type AppType struct {

	// Plugin represents an application used as a Nagios plugin.
	Plugin bool

	// Inspector represents an application used for one-off or isolated
	// checks. Unlike a Nagios plugin which is focused on specific attributes
	// resulting in a severity-based outcome, an Inspector application is
	// intended for examining a small set of targets for
	// informational/troubleshooting purposes.
	Inspector bool
}

AppType represents the type of application that is being configured/initialized. Not all application types will use the same features and as a result will not accept the same flags. Unless noted otherwise, each of the application types are incompatible with each other, though some flags are common to all types.

type Config

type Config struct {

	// LoggingLevel is the supported logging level for this application.
	LoggingLevel string

	// Log is an embedded zerolog Logger initialized via config.New().
	Log zerolog.Logger

	// InspectorSettings is the collection of settings specific to the
	// Inspector application type.
	InspectorSettings InspectorSettings

	// EmitBranding controls whether "generated by" text is included at the
	// bottom of application output. This output is included in the Nagios
	// dashboard and notifications. This output may not mix well with branding
	// output from other tools such as atc0005/send2teams which also insert
	// their own branding output.
	EmitBranding bool

	// ShowVersion is a flag indicating whether the user opted to display only
	// the version string and then immediately exit the application.
	ShowVersion bool

	// ShowHelp indicates whether the user opted to display usage information
	// and exit the application.
	ShowHelp bool
	// contains filtered or unexported fields
}

Config represents the application configuration as specified via command-line flags.

func New

func New(appType AppType) (*Config, error)

New is a factory function that produces a new Config object based on user provided flag and config file values. It is responsible for validating user-provided values and initializing the logging settings used by this application.

func (*Config) Help

func (c *Config) Help() string

Help emits application usage information to the previously configured destination for usage and error messages.

type InspectorSettings

type InspectorSettings struct {
	// ShowAll indicates whether the user opted to display information for ALL
	// processes. This can produce a lot of output
	ShowAll bool
}

InspectorSettings is the collection of settings specific to the Inspector application type.