Simple script that allows you to get experience with failure rate

failure_rate.go

package main

import (
	"fmt"
	"math/rand"
	"time"
)

func init() {
	rand.Seed(time.Now().UnixNano())
}

const failureRate = 25
const numOfExperiments = 1e3

func main() {
	component1 := component(failureRate)
	component2 := component(failureRate)

	var results = make(map[bool]int)
	for i := 0; i < numOfExperiments; i++ {
		r := callAnd(component1, component2)
		results[r]++
	}

	fmt.Println("Ok: ", results[true])
	fmt.Println("Failures: ", results[false])
	fmt.Printf("Failure rate %v\n", float64(results[false]) / float64(results[true] + results[false]))
}

type callable func() bool

// отказ одного из компонентов приводит к отказу всего метода
func callAnd(components ...callable) bool {
	for _, component := range components {
		if !component() {
			return false
		}
	}

	return true
}

func callOr(components ...callable) bool {
	for _, component := range components {
		if component() {
			return true
		}
	}

	return false
}

func component(failureRate int) callable {
	if failureRate < 0 || failureRate > 100 {
		panic("wrong failure rate")
	}

	return func() bool {
		r := rand.Intn(100)
		return failureRate <= r
	}
}