health

Documentation

Overview

Package health provides utilities for monitoring the healthiness of an application.

Index

• type AndMonitor
  • func And(ms ...Monitor) AndMonitor
  • func (am AndMonitor) Healthy(ctx context.Context) (bool, error)
• type Binary
  • func (b *Binary) Healthy(ctx context.Context) (bool, error)
  • func (b *Binary) MarkHealthy()
  • func (b *Binary) MarkUnhealthy()
• type Monitor
• type OrMonitor
  • func Or(ms ...Monitor) OrMonitor
  • func (om OrMonitor) Healthy(ctx context.Context) (bool, error)

Examples

• And
• Binary
• Or

Types

type AndMonitor

type AndMonitor []Monitor

AndMonitor is a collection of [Monitor]s which follows the logical AND (&&) semantics for determining its own healthy/unhealthy state.

In the case of an error it will fail fast.

func And

func And(ms ...Monitor) AndMonitor

And is a simple helper for initializing a AndMonitor in a more functional style.

Example

var a Binary
var b Binary

and := And(&a, &b)

healthy, _ := and.Healthy(context.Background())
fmt.Println(healthy)

a.MarkHealthy()

healthy, _ = and.Healthy(context.Background())
fmt.Println(healthy)

b.MarkHealthy()

healthy, _ = and.Healthy(context.Background())
fmt.Println(healthy)

Output:

false
false
true

func (AndMonitor) Healthy

func (am AndMonitor) Healthy(ctx context.Context) (bool, error)

Healthy implements the Monitor interface.

type Binary

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

Binary is a Monitor which simply has 2 states: healthy or unhealthy. It is safe for concurrent use. The zero value represents an unhealthy state.

Example

var b Binary

healthy, _ := b.Healthy(context.Background())
fmt.Println(healthy)

b.MarkHealthy()

healthy, _ = b.Healthy(context.Background())
fmt.Println(healthy)

b.MarkUnhealthy()

healthy, _ = b.Healthy(context.Background())
fmt.Println(healthy)

Output:

false
true
false

func (*Binary) Healthy

func (b *Binary) Healthy(ctx context.Context) (bool, error)

Healthy implements the Monitor interface.

func (*Binary) MarkHealthy

func (b *Binary) MarkHealthy()

MarkHealthy changes that state to healthy.

func (*Binary) MarkUnhealthy

func (b *Binary) MarkUnhealthy()

MarkUnhealthy changes the state to unhealthy.

type Monitor

type Monitor interface {
	Healthy(context.Context) (bool, error)
}

Monitor represents anything which can report its current state of health.

type OrMonitor

type OrMonitor []Monitor

OrMonitor is a collection of [Monitor]s which follows the logical OR (||) semantics for determining its own healthy/unhealthy state.

It will check all [Monitor]s and if any errors are encountered they will be collected and returned as a single joined error via errors.Join.

func Or

func Or(ms ...Monitor) OrMonitor

Or is a simple helper for initializing a OrMonitor in a more functional style.

Example

var a Binary
var b Binary

or := Or(&a, &b)

healthy, _ := or.Healthy(context.Background())
fmt.Println(healthy)

a.MarkHealthy()

healthy, _ = or.Healthy(context.Background())
fmt.Println(healthy)

b.MarkHealthy()

healthy, _ = or.Healthy(context.Background())
fmt.Println(healthy)

Output:

false
true
true

func (OrMonitor) Healthy

func (om OrMonitor) Healthy(ctx context.Context) (bool, error)

Healthy implements the Monitor interface.