chore: remove circuit-breaker module and tests

Delete src/Utils/circuit-breaker.ts (767 lines) and the corresponding
test file src/__tests__/Utils/circuit-breaker.test.ts (371 lines).

Replaced by src/Utils/bounded-retry.ts (added in earlier commit). All
remaining circuit-breaker references in the codebase are explanatory
comments in code that previously used circuit breakers — kept for
git-history context.

Final state: 35/35 test suites pass, 809 tests pass.
This commit is contained in:
Renato Alcara
2026-04-26 22:52:18 -03:00
parent b70d144699
commit 24329e9ba1
2 changed files with 0 additions and 1137 deletions
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@@ -1,766 +0,0 @@
/**
* Circuit Breaker Pattern Implementation
*
* Provides protection against cascading failures by monitoring operation outcomes
* and temporarily blocking requests when failure thresholds are exceeded.
*
* States:
* - CLOSED: Normal operation, requests pass through
* - OPEN: Failures exceeded threshold, requests are blocked
* - HALF_OPEN: Testing recovery, limited requests allowed
*
* @module Utils/circuit-breaker
*/
import { EventEmitter } from 'events'
import { metrics } from './prometheus-metrics.js'
/**
* Circuit breaker operational states
*/
export type CircuitState = 'closed' | 'open' | 'half-open'
/**
* Failure record with timestamp for sliding window tracking
*/
export interface FailureRecord {
timestamp: number
error: Error
}
/**
* Circuit breaker configuration options
*/
export interface CircuitBreakerOptions {
/** Unique identifier for this circuit breaker (used in metrics/logging) */
name: string
/** Number of failures within the window to trigger OPEN state (default: 5) */
failureThreshold?: number
/** Time window in ms for counting failures (default: 60000) */
failureWindow?: number
/** Number of successes required in HALF_OPEN to return to CLOSED (default: 2) */
successThreshold?: number
/** Time in ms to wait before transitioning from OPEN to HALF_OPEN (default: 30000) */
resetTimeout?: number
/** Timeout for individual operations in ms (default: 10000) */
timeout?: number
/** Minimum number of requests before circuit can trip (default: 5) */
volumeThreshold?: number
/** Predicate to determine if an error should count as a failure */
shouldCountError?: (error: Error) => boolean
/** Whether to collect Prometheus metrics (default: true) */
collectMetrics?: boolean
/** Fallback function when circuit is OPEN */
fallback?: <T>() => T | Promise<T>
/** Callback when state changes */
onStateChange?: (from: CircuitState, to: CircuitState) => void
/** Callback on failure */
onFailure?: (error: Error) => void
/** Callback on success */
onSuccess?: () => void
/** Callback when circuit opens */
onOpen?: () => void
/** Callback when circuit closes */
onClose?: () => void
/** Callback when circuit enters half-open */
onHalfOpen?: () => void
}
/**
* Circuit breaker statistics
*/
export interface CircuitBreakerStats {
state: CircuitState
failures: number
successes: number
consecutiveFailures: number
consecutiveSuccesses: number
totalCalls: number
totalFailures: number
totalSuccesses: number
totalRejected: number
failureRate: number
lastFailureTime?: number
lastSuccessTime?: number
lastStateChange?: number
isOpen: boolean
isClosed: boolean
isHalfOpen: boolean
}
/**
* Error thrown when circuit is OPEN and request is rejected
*/
export class CircuitOpenError extends Error {
constructor(
public readonly circuitName: string,
public readonly state: CircuitState
) {
super(`Circuit breaker "${circuitName}" is ${state}`)
this.name = 'CircuitOpenError'
}
}
/**
* Error thrown when operation exceeds timeout
*/
export class CircuitTimeoutError extends Error {
constructor(
public readonly circuitName: string,
public readonly timeoutMs: number
) {
super(`Circuit breaker "${circuitName}" operation timed out after ${timeoutMs}ms`)
this.name = 'CircuitTimeoutError'
}
}
/**
* Circuit Breaker implementation with sliding window failure tracking
*
* @example
* ```typescript
* const breaker = new CircuitBreaker({
* name: 'whatsapp-api',
* failureThreshold: 5,
* resetTimeout: 30000
* })
*
* try {
* const result = await breaker.execute(() => sendMessage(msg))
* } catch (error) {
* if (error instanceof CircuitOpenError) {
* // Circuit is open, use fallback
* }
* }
* ```
*/
export class CircuitBreaker extends EventEmitter {
private state: CircuitState = 'closed'
private failureRecords: FailureRecord[] = []
private consecutiveFailures = 0
private consecutiveSuccesses = 0
private totalCalls = 0
private totalFailures = 0
private totalSuccesses = 0
private totalRejected = 0
private lastFailureTime?: number
private lastSuccessTime?: number
private lastStateChange: number
private resetTimer?: ReturnType<typeof setTimeout>
private readonly options: Required<CircuitBreakerOptions>
constructor(options: CircuitBreakerOptions) {
super()
this.options = {
name: options.name,
failureThreshold: options.failureThreshold ?? 5,
failureWindow: options.failureWindow ?? 60000,
successThreshold: options.successThreshold ?? 2,
resetTimeout: options.resetTimeout ?? 30000,
timeout: options.timeout ?? 10000,
volumeThreshold: options.volumeThreshold ?? 5,
shouldCountError: options.shouldCountError ?? (() => true),
collectMetrics: options.collectMetrics ?? true,
fallback:
options.fallback ??
(() => {
throw new CircuitOpenError(this.options.name, this.state)
}),
onStateChange: options.onStateChange ?? (() => {}),
onFailure: options.onFailure ?? (() => {}),
onSuccess: options.onSuccess ?? (() => {}),
onOpen: options.onOpen ?? (() => {}),
onClose: options.onClose ?? (() => {}),
onHalfOpen: options.onHalfOpen ?? (() => {})
}
this.lastStateChange = Date.now()
}
/**
* Check if the circuit allows execution
*/
canExecute(): boolean {
if (this.state === 'closed') {
return true
}
if (this.state === 'open') {
return false
}
// HALF_OPEN: allow limited requests for testing
return true
}
/**
* Execute an async operation with circuit breaker protection
*/
async execute<T>(operation: () => T | Promise<T>): Promise<T> {
this.totalCalls++
// Check if circuit allows execution
if (this.state === 'open') {
this.totalRejected++
if (this.options.collectMetrics) {
metrics.errors.inc({ category: 'circuit_breaker', code: 'rejected' })
}
return this.options.fallback() as T
}
// Execute with timeout protection
try {
const result = await this.executeWithTimeout(operation)
this.recordSuccess()
return result
} catch (error) {
this.recordFailure(error as Error)
throw error
}
}
/**
* Execute a synchronous operation with circuit breaker protection
*/
executeSync<T>(operation: () => T): T {
this.totalCalls++
if (this.state === 'open') {
this.totalRejected++
if (this.options.collectMetrics) {
metrics.errors.inc({ category: 'circuit_breaker', code: 'rejected' })
}
return this.options.fallback() as T
}
try {
const result = operation()
this.recordSuccess()
return result
} catch (error) {
this.recordFailure(error as Error)
throw error
}
}
/**
* Execute operation with timeout wrapper
*/
private async executeWithTimeout<T>(operation: () => T | Promise<T>): Promise<T> {
return new Promise<T>((resolve, reject) => {
const timer = setTimeout(() => {
reject(new CircuitTimeoutError(this.options.name, this.options.timeout))
}, this.options.timeout)
Promise.resolve(operation())
.then(result => {
clearTimeout(timer)
resolve(result)
})
.catch(error => {
clearTimeout(timer)
reject(error)
})
})
}
/**
* Record a successful operation
*/
private recordSuccess(): void {
this.totalSuccesses++
this.lastSuccessTime = Date.now()
this.consecutiveSuccesses++
this.consecutiveFailures = 0
if (this.options.collectMetrics) {
metrics.socketEvents.inc({ event: 'circuit_success' })
}
this.options.onSuccess()
this.emit('success')
// In HALF_OPEN state, check if we can close the circuit
if (this.state === 'half-open') {
if (this.consecutiveSuccesses >= this.options.successThreshold) {
this.transitionTo('closed')
}
}
}
/**
* Record a failed operation
*/
private recordFailure(error: Error): void {
// Check if this error should count as a failure
if (!this.options.shouldCountError(error)) {
return
}
const now = Date.now()
this.totalFailures++
this.lastFailureTime = now
this.consecutiveFailures++
this.consecutiveSuccesses = 0
// Add to failure records for sliding window
this.failureRecords.push({ timestamp: now, error })
// Clean old failures outside the window
this.cleanOldFailures()
if (this.options.collectMetrics) {
metrics.errors.inc({ category: 'circuit_breaker', code: 'failure' })
}
this.options.onFailure(error)
this.emit('failure', error)
// State transition logic
if (this.state === 'half-open') {
// Any failure in HALF_OPEN immediately reopens the circuit
this.transitionTo('open')
} else if (this.state === 'closed') {
// Check if we should trip the circuit
const recentFailures = this.failureRecords.length
if (this.totalCalls >= this.options.volumeThreshold && recentFailures >= this.options.failureThreshold) {
this.transitionTo('open')
}
}
}
/**
* Remove failure records outside the sliding window
*/
private cleanOldFailures(): void {
const cutoff = Date.now() - this.options.failureWindow
this.failureRecords = this.failureRecords.filter(record => record.timestamp > cutoff)
}
/**
* Transition to a new state
*/
private transitionTo(newState: CircuitState): void {
const oldState = this.state
if (oldState === newState) {
return
}
this.state = newState
this.lastStateChange = Date.now()
// Clear existing reset timer
if (this.resetTimer) {
clearTimeout(this.resetTimer)
this.resetTimer = undefined
}
// State-specific actions
switch (newState) {
case 'closed':
this.consecutiveFailures = 0
this.consecutiveSuccesses = 0
this.failureRecords = []
this.options.onClose()
this.emit('close')
break
case 'open':
this.consecutiveSuccesses = 0
this.options.onOpen()
this.emit('open')
// Record circuit breaker trip metric
if (this.options.collectMetrics) {
metrics.circuitBreakerTrips?.inc({ name: this.options.name })
}
// Schedule transition to HALF_OPEN
this.resetTimer = setTimeout(() => {
this.transitionTo('half-open')
}, this.options.resetTimeout)
break
case 'half-open':
this.consecutiveSuccesses = 0
this.consecutiveFailures = 0
this.options.onHalfOpen()
this.emit('half-open')
break
}
this.options.onStateChange(oldState, newState)
this.emit('state-change', { from: oldState, to: newState })
}
/**
* Manually trip the circuit to OPEN state
*/
trip(): void {
this.transitionTo('open')
}
/**
* Manually reset the circuit to CLOSED state
*/
reset(): void {
this.transitionTo('closed')
}
/**
* Get current circuit state
*/
getState(): CircuitState {
return this.state
}
/**
* Check if circuit is OPEN
*/
isOpen(): boolean {
return this.state === 'open'
}
/**
* Check if circuit is CLOSED
*/
isClosed(): boolean {
return this.state === 'closed'
}
/**
* Check if circuit is HALF_OPEN
*/
isHalfOpen(): boolean {
return this.state === 'half-open'
}
/**
* Get circuit breaker statistics
*/
getStats(): CircuitBreakerStats {
this.cleanOldFailures()
const failureRate = this.totalCalls > 0 ? (this.totalFailures / this.totalCalls) * 100 : 0
return {
state: this.state,
failures: this.failureRecords.length,
successes: this.consecutiveSuccesses,
consecutiveFailures: this.consecutiveFailures,
consecutiveSuccesses: this.consecutiveSuccesses,
totalCalls: this.totalCalls,
totalFailures: this.totalFailures,
totalSuccesses: this.totalSuccesses,
totalRejected: this.totalRejected,
failureRate,
lastFailureTime: this.lastFailureTime,
lastSuccessTime: this.lastSuccessTime,
lastStateChange: this.lastStateChange,
isOpen: this.isOpen(),
isClosed: this.isClosed(),
isHalfOpen: this.isHalfOpen()
}
}
/**
* Get circuit breaker name
*/
getName(): string {
return this.options.name
}
/**
* Destroy circuit breaker and clean up resources
*/
destroy(): void {
if (this.resetTimer) {
clearTimeout(this.resetTimer)
}
this.failureRecords = []
this.removeAllListeners()
}
}
/**
* Factory function to create a circuit breaker
*/
export function createCircuitBreaker(options: CircuitBreakerOptions): CircuitBreaker {
return new CircuitBreaker(options)
}
/**
* Registry for managing multiple circuit breakers
*/
export class CircuitBreakerRegistry {
private breakers: Map<string, CircuitBreaker> = new Map()
/**
* Get or create a circuit breaker by name
*/
get(name: string, options?: Omit<CircuitBreakerOptions, 'name'>): CircuitBreaker {
if (!this.breakers.has(name)) {
const breaker = new CircuitBreaker({ ...options, name })
this.breakers.set(name, breaker)
}
return this.breakers.get(name)!
}
/**
* Check if a circuit breaker exists
*/
has(name: string): boolean {
return this.breakers.has(name)
}
/**
* Remove a circuit breaker
*/
remove(name: string): boolean {
const breaker = this.breakers.get(name)
if (breaker) {
breaker.destroy()
return this.breakers.delete(name)
}
return false
}
/**
* Get all circuit breakers
*/
getAll(): Map<string, CircuitBreaker> {
return new Map(this.breakers)
}
/**
* Get statistics for all circuit breakers
*/
getAllStats(): Record<string, CircuitBreakerStats> {
const stats: Record<string, CircuitBreakerStats> = {}
for (const [name, breaker] of this.breakers) {
stats[name] = breaker.getStats()
}
return stats
}
/**
* Reset all circuit breakers to CLOSED state
*/
resetAll(): void {
for (const breaker of this.breakers.values()) {
breaker.reset()
}
}
/**
* Destroy all circuit breakers
*/
destroyAll(): void {
for (const breaker of this.breakers.values()) {
breaker.destroy()
}
this.breakers.clear()
}
}
/**
* Global circuit breaker registry instance
*/
export const globalCircuitRegistry = new CircuitBreakerRegistry()
/**
* Decorator to protect a method with circuit breaker
*
* @example
* ```typescript
* class MyService {
* @circuitBreaker({ failureThreshold: 3 })
* async fetchData() {
* return await api.getData()
* }
* }
* ```
*/
export function circuitBreaker(options: Omit<CircuitBreakerOptions, 'name'> & { name?: string } = {}) {
return function (
_target: unknown,
propertyKey: string,
descriptor: TypedPropertyDescriptor<(...args: unknown[]) => unknown>
) {
const originalMethod = descriptor.value
if (!originalMethod) return descriptor
const name = options.name || propertyKey
const breaker = globalCircuitRegistry.get(name, options)
descriptor.value = async function (...args: unknown[]): Promise<unknown> {
return breaker.execute(() => originalMethod.apply(this, args))
}
return descriptor
}
}
/**
* Wrap a function with circuit breaker protection
*
* @example
* ```typescript
* const protectedFetch = withCircuitBreaker(
* fetchData,
* { name: 'api-fetch', failureThreshold: 5 }
* )
* ```
*/
// eslint-disable-next-line space-before-function-paren
export function withCircuitBreaker<T extends (...args: unknown[]) => unknown>(
fn: T,
options: CircuitBreakerOptions
): T {
const breaker = new CircuitBreaker(options)
return (async (...args: Parameters<T>): Promise<ReturnType<T>> => {
return breaker.execute(() => fn(...args)) as Promise<ReturnType<T>>
}) as unknown as T
}
/**
* Get health status of all circuit breakers
*/
export function getCircuitHealth(): {
healthy: boolean
openCircuits: string[]
stats: Record<string, CircuitBreakerStats>
} {
const stats = globalCircuitRegistry.getAllStats()
const openCircuits: string[] = []
for (const [name, stat] of Object.entries(stats)) {
if (stat.isOpen) {
openCircuits.push(name)
}
}
return {
healthy: openCircuits.length === 0,
openCircuits,
stats
}
}
/**
* Create a pre-configured circuit breaker for WhatsApp PreKey operations
*
* This circuit breaker is optimized for handling encryption/session errors
* that commonly occur with WhatsApp's Signal protocol implementation.
*
* @example
* ```typescript
* const preKeyBreaker = createPreKeyCircuitBreaker()
*
* async function sendEncryptedMessage(msg) {
* return preKeyBreaker.execute(async () => {
* return await encryptAndSend(msg)
* })
* }
* ```
*/
export function createPreKeyCircuitBreaker(customOptions?: Partial<CircuitBreakerOptions>): CircuitBreaker {
const preKeyErrorPatterns = ['prekey', 'pre-key', 'session', 'signal', 'encrypt', 'decrypt', 'cipher', 'key']
return new CircuitBreaker({
name: 'prekey-operations',
failureThreshold: 5,
failureWindow: 60000,
resetTimeout: 30000,
successThreshold: 2,
shouldCountError: (error: Error) => {
const message = error.message.toLowerCase()
return preKeyErrorPatterns.some(pattern => message.includes(pattern))
},
...customOptions
})
}
/**
* Create a circuit breaker for WebSocket connection operations
*/
export function createConnectionCircuitBreaker(customOptions?: Partial<CircuitBreakerOptions>): CircuitBreaker {
const connectionErrorPatterns = [
'econnrefused',
'econnreset',
'etimedout',
'enotfound',
'socket',
'websocket',
'connection',
'network'
]
// Normal WS lifecycle status codes that must NEVER trip the query circuit breaker.
// These are transient events that happen on every reconnect and carry no information
// about persistent server-side failures. The reconnection logic in makeSocket handles
// them independently.
const WS_LIFECYCLE_STATUS_CODES = new Set([
428, // connectionClosed
408, // connectionLost / timedOut
440, // connectionReplaced
])
return new CircuitBreaker({
name: 'connection-operations',
failureThreshold: 3,
failureWindow: 30000,
resetTimeout: 60000,
successThreshold: 1,
shouldCountError: (error: Error) => {
// CircuitTimeoutError messages embed the circuit name (e.g. "socket-query"), which
// accidentally matches the "socket" pattern below and causes a self-reinforcing loop
// where the breaker's own timeouts keep tripping the breaker. Exclude them explicitly.
if (error instanceof CircuitTimeoutError) return false
// Exclude normal WS reconnect events (Connection Closed, Connection Lost, Timed Out, etc.).
// These are not server-side failures — they happen on every restart/redeploy and should
// never cause the circuit to open. If we counted them, the 3 concurrent parallel
// post-login queries (sendPassiveIq, uploadPreKeysToServerIfRequired, digestKeyBundle) could all
// fail simultaneously when the WS drops, instantly opening the circuit and blocking
// profile-picture fetches and message delivery for the next 30 s.
const statusCode = (error as { output?: { statusCode?: number } })?.output?.statusCode
if (statusCode !== undefined && WS_LIFECYCLE_STATUS_CODES.has(statusCode)) return false
const message = error.message.toLowerCase()
const code = (error as NodeJS.ErrnoException).code?.toLowerCase() || ''
return connectionErrorPatterns.some(pattern => message.includes(pattern) || code.includes(pattern))
},
...customOptions
})
}
/**
* Create a circuit breaker for message sending operations
*/
export function createMessageCircuitBreaker(customOptions?: Partial<CircuitBreakerOptions>): CircuitBreaker {
return new CircuitBreaker({
name: 'message-operations',
failureThreshold: 5,
failureWindow: 60000,
resetTimeout: 15000,
successThreshold: 2,
timeout: 30000,
...customOptions
})
}
export default CircuitBreaker
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/**
* Testes unitários para circuit-breaker.ts
*/
import { afterEach, beforeEach, describe, expect, it } from '@jest/globals'
import {
CircuitBreaker,
CircuitBreakerRegistry,
CircuitOpenError,
type CircuitState,
CircuitTimeoutError,
createCircuitBreaker,
getCircuitHealth,
globalCircuitRegistry,
withCircuitBreaker
} from '../../Utils/circuit-breaker.js'
describe('CircuitBreaker', () => {
let breaker: CircuitBreaker
beforeEach(() => {
breaker = createCircuitBreaker({
name: 'test',
failureThreshold: 3,
successThreshold: 2,
resetTimeout: 100,
timeout: 1000,
volumeThreshold: 3,
collectMetrics: false
})
})
afterEach(() => {
breaker.destroy()
})
describe('initial state', () => {
it('should start in closed state', () => {
expect(breaker.getState()).toBe('closed')
expect(breaker.isClosed()).toBe(true)
expect(breaker.isOpen()).toBe(false)
expect(breaker.isHalfOpen()).toBe(false)
})
})
describe('successful operations', () => {
it('should execute successful operations', async () => {
const result = await breaker.execute(() => 'success')
expect(result).toBe('success')
})
it('should execute async operations', async () => {
const result = await breaker.execute(async () => {
await new Promise(resolve => setTimeout(resolve, 10))
return 'async success'
})
expect(result).toBe('async success')
})
it('should track successful calls in stats', async () => {
await breaker.execute(() => 'success')
await breaker.execute(() => 'success')
const stats = breaker.getStats()
expect(stats.totalCalls).toBe(2)
expect(stats.totalSuccesses).toBe(2)
expect(stats.totalFailures).toBe(0)
})
})
describe('failure handling', () => {
it('should open after reaching failure threshold', async () => {
const failingOp = () => {
throw new Error('Failure')
}
// Reach failure threshold
for (let i = 0; i < 3; i++) {
await expect(breaker.execute(failingOp)).rejects.toThrow('Failure')
}
expect(breaker.isOpen()).toBe(true)
})
it('should not open before reaching threshold', async () => {
const failingOp = () => {
throw new Error('Failure')
}
// Below threshold
for (let i = 0; i < 2; i++) {
await expect(breaker.execute(failingOp)).rejects.toThrow('Failure')
}
expect(breaker.isClosed()).toBe(true)
})
it('should reset failure count on success', async () => {
const failingOp = () => {
throw new Error('Failure')
}
await expect(breaker.execute(failingOp)).rejects.toThrow()
await expect(breaker.execute(failingOp)).rejects.toThrow()
// Success resets failures
await breaker.execute(() => 'success')
// Only 1 more failure needed (already have 2 in window, need 3 total)
await expect(breaker.execute(failingOp)).rejects.toThrow()
// Should open now (3 failures in window)
expect(breaker.isOpen()).toBe(true)
})
})
describe('open state', () => {
beforeEach(async () => {
// Force open
breaker.trip()
})
it('should reject operations when open', async () => {
await expect(breaker.execute(() => 'success')).rejects.toThrow(CircuitOpenError)
})
it('should transition to half-open after reset timeout', async () => {
await new Promise(resolve => setTimeout(resolve, 150))
expect(breaker.isHalfOpen()).toBe(true)
})
})
describe('half-open state', () => {
beforeEach(async () => {
breaker.trip()
await new Promise(resolve => setTimeout(resolve, 150))
})
it('should close after success threshold', async () => {
expect(breaker.isHalfOpen()).toBe(true)
// Success threshold is 2
await breaker.execute(() => 'success')
await breaker.execute(() => 'success')
expect(breaker.isClosed()).toBe(true)
})
it('should reopen on failure', async () => {
expect(breaker.isHalfOpen()).toBe(true)
await expect(
breaker.execute(() => {
throw new Error('Failure')
})
).rejects.toThrow()
expect(breaker.isOpen()).toBe(true)
})
})
describe('manual controls', () => {
it('should force open with trip()', () => {
breaker.trip()
expect(breaker.isOpen()).toBe(true)
})
it('should force close with reset()', async () => {
breaker.trip()
breaker.reset()
expect(breaker.isClosed()).toBe(true)
})
})
describe('timeout', () => {
it('should timeout slow operations', async () => {
const slowBreaker = createCircuitBreaker({
name: 'slow',
timeout: 50,
collectMetrics: false
})
await expect(slowBreaker.execute(() => new Promise(resolve => setTimeout(resolve, 200)))).rejects.toThrow(
CircuitTimeoutError
)
slowBreaker.destroy()
})
})
describe('events', () => {
it('should emit state-change event', async () => {
const stateChanges: Array<{ from: CircuitState; to: CircuitState }> = []
breaker.on('state-change', change => {
stateChanges.push(change)
})
breaker.trip()
breaker.reset()
expect(stateChanges).toHaveLength(2)
expect(stateChanges[0]).toEqual({ from: 'closed', to: 'open' })
expect(stateChanges[1]).toEqual({ from: 'open', to: 'closed' })
})
it('should emit success and failure events', async () => {
let successCount = 0
let failureCount = 0
breaker.on('success', () => successCount++)
breaker.on('failure', () => failureCount++)
await breaker.execute(() => 'success')
await expect(
breaker.execute(() => {
throw new Error()
})
).rejects.toThrow()
expect(successCount).toBe(1)
expect(failureCount).toBe(1)
})
})
describe('isFailure predicate', () => {
it('should use custom isFailure predicate', async () => {
const customBreaker = createCircuitBreaker({
name: 'custom',
failureThreshold: 1,
volumeThreshold: 1,
shouldCountError: (error: any) => error.message !== 'Ignored',
collectMetrics: false
})
// This error should be ignored
await expect(
customBreaker.execute(() => {
throw new Error('Ignored')
})
).rejects.toThrow()
expect(customBreaker.isClosed()).toBe(true)
// This should trip the breaker
await expect(
customBreaker.execute(() => {
throw new Error('Real failure')
})
).rejects.toThrow()
expect(customBreaker.isOpen()).toBe(true)
customBreaker.destroy()
})
})
describe('sync operations', () => {
it('should execute sync operations', () => {
const result = breaker.executeSync(() => 'sync result')
expect(result).toBe('sync result')
})
it('should handle sync failures', () => {
expect(() =>
breaker.executeSync(() => {
throw new Error('Sync failure')
})
).toThrow('Sync failure')
})
})
})
describe('CircuitBreakerRegistry', () => {
let registry: CircuitBreakerRegistry
beforeEach(() => {
registry = new CircuitBreakerRegistry()
})
afterEach(() => {
registry.destroyAll()
})
it('should create and retrieve circuit breakers', () => {
const breaker1 = registry.get('test1')
const breaker2 = registry.get('test1')
expect(breaker1).toBe(breaker2)
})
it('should check if breaker exists', () => {
registry.get('exists')
expect(registry.has('exists')).toBe(true)
expect(registry.has('notexists')).toBe(false)
})
it('should remove breaker', () => {
registry.get('toRemove')
expect(registry.remove('toRemove')).toBe(true)
expect(registry.has('toRemove')).toBe(false)
})
it('should get all stats', () => {
registry.get('breaker1')
registry.get('breaker2')
const stats = registry.getAllStats()
expect(stats).toHaveProperty('breaker1')
expect(stats).toHaveProperty('breaker2')
})
it('should reset all breakers', async () => {
const breaker = registry.get('test')
breaker.trip()
registry.resetAll()
expect(breaker.isClosed()).toBe(true)
})
})
describe('withCircuitBreaker', () => {
it('should wrap function with circuit breaker', async () => {
let callCount = 0
const protectedFn = withCircuitBreaker(
async () => {
callCount++
return 'result'
},
{
name: 'wrapped-fn',
collectMetrics: false
}
)
const result = await protectedFn()
expect(result).toBe('result')
expect(callCount).toBe(1)
})
})
describe('getCircuitHealth', () => {
beforeEach(() => {
globalCircuitRegistry.destroyAll()
})
it('should report healthy when all circuits closed', () => {
globalCircuitRegistry.get('healthy1')
globalCircuitRegistry.get('healthy2')
const health = getCircuitHealth()
expect(health.healthy).toBe(true)
expect(health.openCircuits).toHaveLength(0)
})
it('should report unhealthy when circuit is open', () => {
const breaker = globalCircuitRegistry.get('unhealthy')
breaker.trip()
const health = getCircuitHealth()
expect(health.healthy).toBe(false)
expect(health.openCircuits).toContain('unhealthy')
})
})