Circuit Breaker Pattern: Building Resilient Microservices

Introduction

In distributed systems, a single failing service can trigger a cascade of failures across your entire infrastructure. When Service A calls Service B, and Service B is slow or unresponsive, Service A’s threads get blocked waiting for responses. As requests pile up, Service A exhausts its thread pool and becomes unresponsive itself. Now Service C, which depends on Service A, starts failing too. Within minutes, your entire system is down.

The circuit breaker pattern prevents this cascade by monitoring calls to external services and “opening the circuit” when failures exceed a threshold. Once open, the circuit breaker immediately rejects requests without attempting the call, giving the failing service time to recover while keeping your system responsive.

This pattern is named after electrical circuit breakers in your home — when too much current flows through, the breaker trips and stops the flow to prevent damage.

How Circuit Breakers Work

A circuit breaker wraps calls to external services and tracks their success and failure rates. It operates in three states:

%%{init: {'theme':'base', 'themeVariables': { 'fontSize':'16px', 'fontFamily':'system-ui'}}}%%
graph LR
    Start([Start]) --> Closed[CLOSED]
    Closed -->|Failures exceed threshold| Open[OPEN]
    Open -->|Timeout expires| HalfOpen[HALF-OPEN]
    HalfOpen -->|Tests succeed| Closed
    HalfOpen -->|Tests fail| Open
    
    style Closed fill:#10b981,stroke:#059669,stroke-width:3px,color:#fff
    style Open fill:#ef4444,stroke:#dc2626,stroke-width:3px,color:#fff
    style HalfOpen fill:#f59e0b,stroke:#d97706,stroke-width:3px,color:#fff
    style Start fill:#6366f1,stroke:#4f46e5,stroke-width:2px,color:#fff

State Descriptions:

CLOSED: Normal operation - all requests pass through to the service
OPEN: Failing fast - requests are rejected immediately without calling the service
HALF-OPEN: Testing recovery - limited test requests are allowed through

State Transitions

Closed State (Normal Operation)

All requests pass through to the downstream service
Circuit breaker tracks success and failure rates
If failure rate exceeds threshold, transition to Open

Open State (Failing Fast)

All requests fail immediately without calling the service
Returns a predefined error or fallback response
After a timeout period, transition to Half-Open

Half-Open State (Testing Recovery)

Allow a limited number of test requests through
If test requests succeed, transition back to Closed
If test requests fail, return to Open state

Core Concepts

Failure Threshold

The circuit breaker monitors a sliding window of recent requests and calculates the failure rate. When failures exceed the configured threshold, the circuit opens.

// Resilience4j configuration
CircuitBreakerConfig config = CircuitBreakerConfig.custom()
    .failureRateThreshold(50)                    // Open at 50% failure rate
    .slidingWindowSize(10)                       // Track last 10 calls
    .minimumNumberOfCalls(5)                     // Need 5 calls before calculating rate
    .waitDurationInOpenState(Duration.ofSeconds(30))  // Stay open for 30s
    .permittedNumberOfCallsInHalfOpenState(3)    // Allow 3 test calls
    .build();

Sliding Window

Circuit breakers use either count-based or time-based sliding windows to aggregate call outcomes:

Count-Based Window: Tracks the last N calls

Simple and predictable
Good for high-traffic services
Example: Last 100 requests

Time-Based Window: Tracks calls within a time period

Better for variable traffic patterns
Adapts to traffic spikes
Example: Last 60 seconds

Timeout and Recovery

After opening, the circuit breaker waits for a configured duration before transitioning to Half-Open. This gives the failing service time to recover without being overwhelmed by requests.

// Polly (.NET) configuration
var circuitBreakerPolicy = Policy
    .Handle<HttpRequestException>()
    .CircuitBreakerAsync(
        exceptionsAllowedBeforeBreaking: 5,
        durationOfBreak: TimeSpan.FromSeconds(30),
        onBreak: (exception, duration) => {
            Console.WriteLine($"Circuit opened for {duration.TotalSeconds}s");
        },
        onReset: () => {
            Console.WriteLine("Circuit closed, service recovered");
        }
    );

Implementation Examples

Java with Resilience4j

Resilience4j is the modern replacement for Netflix Hystrix (now in maintenance mode). It’s lightweight, functional, and designed for Java 8+.

import io.github.resilience4j.circuitbreaker.CircuitBreaker;
import io.github.resilience4j.circuitbreaker.CircuitBreakerConfig;
import io.github.resilience4j.circuitbreaker.CircuitBreakerRegistry;

import java.time.Duration;
import java.util.function.Supplier;

public class PaymentService {
    private final CircuitBreaker circuitBreaker;
    private final ExternalPaymentAPI paymentAPI;

    public PaymentService(ExternalPaymentAPI paymentAPI) {
        this.paymentAPI = paymentAPI;
        
        CircuitBreakerConfig config = CircuitBreakerConfig.custom()
            .failureRateThreshold(50)
            .slowCallRateThreshold(50)
            .slowCallDurationThreshold(Duration.ofSeconds(2))
            .slidingWindowType(CircuitBreakerConfig.SlidingWindowType.COUNT_BASED)
            .slidingWindowSize(10)
            .minimumNumberOfCalls(5)
            .waitDurationInOpenState(Duration.ofSeconds(30))
            .permittedNumberOfCallsInHalfOpenState(3)
            .automaticTransitionFromOpenToHalfOpenEnabled(true)
            .recordExceptions(IOException.class, TimeoutException.class)
            .ignoreExceptions(IllegalArgumentException.class)
            .build();

        CircuitBreakerRegistry registry = CircuitBreakerRegistry.of(config);
        this.circuitBreaker = registry.circuitBreaker("paymentService");
        
        // Register event listeners
        circuitBreaker.getEventPublisher()
            .onStateTransition(event -> 
                System.out.println("Circuit breaker state: " + event.getStateTransition())
            )
            .onError(event -> 
                System.out.println("Call failed: " + event.getThrowable().getMessage())
            );
    }

    public PaymentResult processPayment(PaymentRequest request) {
        Supplier<PaymentResult> decoratedSupplier = CircuitBreaker
            .decorateSupplier(circuitBreaker, () -> paymentAPI.charge(request));
        
        try {
            return decoratedSupplier.get();
        } catch (CallNotPermittedException e) {
            // Circuit is open, return fallback
            return PaymentResult.unavailable("Payment service temporarily unavailable");
        } catch (Exception e) {
            // Other errors
            return PaymentResult.error("Payment failed: " + e.getMessage());
        }
    }
}

.NET with Polly

Polly is the standard resilience library for .NET applications.

using Polly;
using Polly.CircuitBreaker;
using System;
using System.Net.Http;
using System.Threading.Tasks;

public class OrderService
{
    private readonly HttpClient _httpClient;
    private readonly AsyncCircuitBreakerPolicy<HttpResponseMessage> _circuitBreakerPolicy;

    public OrderService(HttpClient httpClient)
    {
        _httpClient = httpClient;
        
        _circuitBreakerPolicy = Policy
            .HandleResult<HttpResponseMessage>(r => !r.IsSuccessStatusCode)
            .Or<HttpRequestException>()
            .Or<TaskCanceledException>()
            .AdvancedCircuitBreakerAsync(
                failureThreshold: 0.5,           // Open at 50% failure rate
                samplingDuration: TimeSpan.FromSeconds(10),
                minimumThroughput: 5,            // Need 5 calls in window
                durationOfBreak: TimeSpan.FromSeconds(30),
                onBreak: (result, duration) =>
                {
                    Console.WriteLine($"Circuit opened for {duration.TotalSeconds}s");
                },
                onReset: () =>
                {
                    Console.WriteLine("Circuit closed");
                },
                onHalfOpen: () =>
                {
                    Console.WriteLine("Circuit half-open, testing...");
                }
            );
    }

    public async Task<Order> GetOrderAsync(string orderId)
    {
        try
        {
            var response = await _circuitBreakerPolicy.ExecuteAsync(async () =>
                await _httpClient.GetAsync($"/api/orders/{orderId}")
            );

            if (response.IsSuccessStatusCode)
            {
                return await response.Content.ReadAsAsync<Order>();
            }

            return Order.NotFound(orderId);
        }
        catch (BrokenCircuitException)
        {
            // Circuit is open, return cached data or default
            return await GetCachedOrderAsync(orderId) 
                ?? Order.Unavailable(orderId);
        }
    }

    private async Task<Order> GetCachedOrderAsync(string orderId)
    {
        // Return cached data if available
        return null;
    }
}

Go Implementation

Go doesn’t have a standard circuit breaker library, but implementing one is straightforward.

package circuitbreaker

import (
    "errors"
    "sync"
    "time"
)

type State int

const (
    StateClosed State = iota
    StateOpen
    StateHalfOpen
)

var (
    ErrCircuitOpen = errors.New("circuit breaker is open")
)

type CircuitBreaker struct {
    maxFailures  int
    timeout      time.Duration
    halfOpenMax  int
    
    mu           sync.RWMutex
    state        State
    failures     int
    lastFailTime time.Time
    halfOpenCalls int
}

func New(maxFailures int, timeout time.Duration, halfOpenMax int) *CircuitBreaker {
    return &CircuitBreaker{
        maxFailures: maxFailures,
        timeout:     timeout,
        halfOpenMax: halfOpenMax,
        state:       StateClosed,
    }
}

func (cb *CircuitBreaker) Call(fn func() error) error {
    cb.mu.Lock()
    
    // Check if we should transition from Open to Half-Open
    if cb.state == StateOpen {
        if time.Since(cb.lastFailTime) > cb.timeout {
            cb.state = StateHalfOpen
            cb.halfOpenCalls = 0
        } else {
            cb.mu.Unlock()
            return ErrCircuitOpen
        }
    }
    
    // Reject if Half-Open and already testing
    if cb.state == StateHalfOpen && cb.halfOpenCalls >= cb.halfOpenMax {
        cb.mu.Unlock()
        return ErrCircuitOpen
    }
    
    if cb.state == StateHalfOpen {
        cb.halfOpenCalls++
    }
    
    cb.mu.Unlock()
    
    // Execute the function
    err := fn()
    
    cb.mu.Lock()
    defer cb.mu.Unlock()
    
    if err != nil {
        cb.onFailure()
        return err
    }
    
    cb.onSuccess()
    return nil
}

func (cb *CircuitBreaker) onSuccess() {
    if cb.state == StateHalfOpen {
        // Successful test call, close the circuit
        cb.state = StateClosed
        cb.failures = 0
        cb.halfOpenCalls = 0
    } else if cb.state == StateClosed {
        // Reset failure count on success
        cb.failures = 0
    }
}

func (cb *CircuitBreaker) onFailure() {
    cb.failures++
    cb.lastFailTime = time.Now()
    
    if cb.state == StateHalfOpen {
        // Test failed, reopen circuit
        cb.state = StateOpen
        cb.halfOpenCalls = 0
    } else if cb.failures >= cb.maxFailures {
        // Too many failures, open circuit
        cb.state = StateOpen
    }
}

func (cb *CircuitBreaker) State() State {
    cb.mu.RLock()
    defer cb.mu.RUnlock()
    return cb.state
}

// Usage example
func main() {
    cb := New(5, 30*time.Second, 3)
    
    err := cb.Call(func() error {
        // Call external service
        resp, err := http.Get("https://api.example.com/data")
        if err != nil {
            return err
        }
        defer resp.Body.Close()
        
        if resp.StatusCode != 200 {
            return errors.New("service returned error")
        }
        
        return nil
    })
    
    if err == ErrCircuitOpen {
        // Circuit is open, use fallback
        fmt.Println("Service unavailable, using cached data")
    } else if err != nil {
        // Other error
        fmt.Printf("Request failed: %v\n", err)
    }
}

Best Practices

1. Configure Thresholds Based on Traffic Patterns

Don’t use the same configuration for all services. High-traffic services need larger sliding windows, while low-traffic services need smaller ones.

// High-traffic service (1000+ req/min)
CircuitBreakerConfig highTraffic = CircuitBreakerConfig.custom()
    .slidingWindowSize(100)
    .minimumNumberOfCalls(20)
    .failureRateThreshold(50)
    .build();

// Low-traffic service (10-50 req/min)
CircuitBreakerConfig lowTraffic = CircuitBreakerConfig.custom()
    .slidingWindowSize(10)
    .minimumNumberOfCalls(5)
    .failureRateThreshold(60)
    .build();

2. Implement Fallback Strategies

When the circuit is open, don’t just return errors. Provide fallback responses:

Return cached data
Return default values
Degrade functionality gracefully
Queue requests for later processing

public UserProfile getUserProfile(String userId) {
    try {
        return circuitBreaker.executeSupplier(() -> 
            userService.fetchProfile(userId)
        );
    } catch (CallNotPermittedException e) {
        // Circuit open, try cache
        UserProfile cached = cache.get(userId);
        if (cached != null) {
            return cached.withStaleWarning();
        }
        // Return minimal profile
        return UserProfile.minimal(userId);
    }
}

3. Monitor Circuit Breaker State

Export circuit breaker metrics to your monitoring system. Track:

State transitions (Closed → Open → Half-Open)
Failure rates
Call duration
Number of rejected calls

// Resilience4j with Micrometer
CircuitBreaker circuitBreaker = registry.circuitBreaker("paymentService");
MeterRegistry meterRegistry = new SimpleMeterRegistry();

TaggedCircuitBreakerMetrics.ofCircuitBreakerRegistry(registry)
    .bindTo(meterRegistry);

// Metrics available:
// - resilience4j.circuitbreaker.state (0=closed, 1=open, 2=half_open)
// - resilience4j.circuitbreaker.calls (success, failure, not_permitted)
// - resilience4j.circuitbreaker.failure.rate

4. Use Different Timeouts for Different Failure Types

Not all failures are equal. Network timeouts might need longer recovery periods than HTTP 500 errors.

var policy = Policy
    .Handle<TimeoutException>()
    .CircuitBreakerAsync(3, TimeSpan.FromMinutes(2))  // Long timeout for network issues
    .WrapAsync(
        Policy
            .Handle<HttpRequestException>()
            .CircuitBreakerAsync(5, TimeSpan.FromSeconds(30))  // Short timeout for HTTP errors
    );

5. Combine with Retry and Timeout Policies

Circuit breakers work best when combined with other resilience patterns:

// Resilience4j combining multiple patterns
Retry retry = Retry.of("paymentService", RetryConfig.custom()
    .maxAttempts(3)
    .waitDuration(Duration.ofMillis(500))
    .build());

TimeLimiter timeLimiter = TimeLimiter.of(TimeLimiterConfig.custom()
    .timeoutDuration(Duration.ofSeconds(2))
    .build());

Supplier<PaymentResult> decoratedSupplier = Decorators
    .ofSupplier(() -> paymentAPI.charge(request))
    .withCircuitBreaker(circuitBreaker)
    .withRetry(retry)
    .withTimeLimiter(timeLimiter)
    .decorate();

Common Pitfalls

1. Setting Thresholds Too Low

Opening the circuit too aggressively can cause unnecessary service degradation. A few failures in a high-traffic system are normal.

Bad: Open after 2 failures

.failureRateThreshold(20)  // Opens at 20% failure rate
.minimumNumberOfCalls(2)   // With only 2 calls

Good: Require statistical significance

.failureRateThreshold(50)  // Opens at 50% failure rate
.minimumNumberOfCalls(10)  // Need at least 10 calls

2. Not Handling Circuit Open State

Failing to provide fallbacks when the circuit is open defeats the purpose of the pattern.

Bad: Propagate the error

public Data getData() {
    return circuitBreaker.executeSupplier(() -> api.fetch());
    // Throws CallNotPermittedException when open
}

Good: Provide fallback

public Data getData() {
    try {
        return circuitBreaker.executeSupplier(() -> api.fetch());
    } catch (CallNotPermittedException e) {
        return cache.getOrDefault(Data.empty());
    }
}

Each external dependency should have its own circuit breaker. Sharing one breaker across multiple endpoints means one failing endpoint can block all others.

Bad: One breaker for entire service

CircuitBreaker breaker = registry.circuitBreaker("externalService");
breaker.executeSupplier(() -> api.getUsers());
breaker.executeSupplier(() -> api.getOrders());  // Blocked if getUsers fails

Good: Separate breakers per endpoint

CircuitBreaker userBreaker = registry.circuitBreaker("externalService-users");
CircuitBreaker orderBreaker = registry.circuitBreaker("externalService-orders");

userBreaker.executeSupplier(() -> api.getUsers());
orderBreaker.executeSupplier(() -> api.getOrders());  // Independent

4. Ignoring Slow Calls

Circuit breakers should track not just failures, but also slow calls that tie up resources.

CircuitBreakerConfig config = CircuitBreakerConfig.custom()
    .failureRateThreshold(50)
    .slowCallRateThreshold(50)              // Also track slow calls
    .slowCallDurationThreshold(Duration.ofSeconds(3))  // >3s is slow
    .build();

Service Mesh Integration

Modern service meshes like Istio and Linkerd implement circuit breakers at the infrastructure level, removing the need for application-level libraries.

Istio Circuit Breaker

apiVersion: networking.istio.io/v1beta1
kind: DestinationRule
metadata:
  name: payment-service
spec:
  host: payment-service
  trafficPolicy:
    connectionPool:
      tcp:
        maxConnections: 100
      http:
        http1MaxPendingRequests: 50
        http2MaxRequests: 100
        maxRequestsPerConnection: 2
    outlierDetection:
      consecutiveErrors: 5
      interval: 30s
      baseEjectionTime: 30s
      maxEjectionPercent: 50
      minHealthPercent: 50

Advantages:

No code changes required
Consistent behavior across all services
Centralized configuration
Language-agnostic

Disadvantages:

Less fine-grained control
Harder to test locally
Requires service mesh infrastructure

Testing Circuit Breakers

Unit Testing

@Test
public void testCircuitOpensAfterFailures() {
    CircuitBreakerConfig config = CircuitBreakerConfig.custom()
        .failureRateThreshold(50)
        .slidingWindowSize(4)
        .minimumNumberOfCalls(4)
        .build();
    
    CircuitBreaker breaker = CircuitBreaker.of("test", config);
    
    // Simulate 3 failures
    for (int i = 0; i < 3; i++) {
        try {
            breaker.executeSupplier(() -> {
                throw new RuntimeException("Service down");
            });
        } catch (Exception e) {
            // Expected
        }
    }
    
    // Circuit should still be closed (need 4 calls minimum)
    assertEquals(CircuitBreaker.State.CLOSED, breaker.getState());
    
    // One more failure should open it
    try {
        breaker.executeSupplier(() -> {
            throw new RuntimeException("Service down");
        });
    } catch (Exception e) {
        // Expected
    }
    
    // Now circuit should be open
    assertEquals(CircuitBreaker.State.OPEN, breaker.getState());
    
    // Next call should fail fast
    assertThrows(CallNotPermittedException.class, () -> {
        breaker.executeSupplier(() -> "success");
    });
}

Integration Testing with Chaos Engineering

Use tools like Chaos Monkey or Toxiproxy to simulate service failures and verify circuit breaker behavior.

# Toxiproxy: Add latency to payment service
toxiproxy-cli toxic add payment-service -t latency -a latency=5000

# Verify circuit breaker opens after threshold
curl http://localhost:8080/api/orders/123
# Should return fallback response after circuit opens

Python Implementation

import time
import threading
from abc import ABC, abstractmethod
from dataclasses import dataclass, field
from enum import Enum
from typing import Callable, TypeVar, Generic
import functools

T = TypeVar('T')

class CircuitState(Enum):
    CLOSED = "closed"
    OPEN = "open"
    HALF_OPEN = "half_open"

@dataclass
class CircuitBreakerConfig:
    failure_threshold: int = 5
    success_threshold: int = 3
    timeout: float = 60.0
    half_open_max_calls: int = 3

class CircuitBreakerOpen(Exception):
    pass

class CircuitBreaker:
    def __init__(self, name: str, config: CircuitBreakerConfig = None):
        self.name = name
        self.config = config or CircuitBreakerConfig()
        self.state = CircuitState.CLOSED
        self.failure_count = 0
        self.success_count = 0
        self.last_failure_time = None
        self.lock = threading.RLock()
        self.call_count = 0

    def call(self, func: Callable[..., T], *args, **kwargs) -> T:
        with self.lock:
            self._check_state()
            if self.state == CircuitState.OPEN:
                raise CircuitBreakerOpen(
                    f"Circuit {self.name} is OPEN. Failing fast."
                )
        try:
            result = func(*args, **kwargs)
            self._on_success()
            return result
        except Exception as e:
            self._on_failure()
            raise

    def _check_state(self):
        if self.state == CircuitState.OPEN:
            if (self.last_failure_time and
                time.time() - self.last_failure_time > self.config.timeout):
                self._transition_to_half_open()

    def _transition_to_half_open(self):
        print(f"[Circuit {self.name}] OPEN -> HALF_OPEN")
        self.state = CircuitState.HALF_OPEN
        self.call_count = 0
        self.success_count = 0

    def _on_success(self):
        with self.lock:
            if self.state == CircuitState.HALF_OPEN:
                self.success_count += 1
                self.call_count += 1
                if (self.success_count >= self.config.success_threshold or
                    self.call_count >= self.config.half_open_max_calls):
                    self._transition_to_closed()
            elif self.state == CircuitState.CLOSED:
                self.failure_count = 0

    def _on_failure(self):
        with self.lock:
            self.failure_count += 1
            self.last_failure_time = time.time()
            if self.state == CircuitState.HALF_OPEN:
                self._transition_to_open()
            elif (self.state == CircuitState.CLOSED and
                  self.failure_count >= self.config.failure_threshold):
                self._transition_to_open()

    def _transition_to_open(self):
        print(f"[Circuit {self.name}] {self.state.value} -> OPEN")
        self.state = CircuitState.OPEN
        self.failure_count = 0

    def _transition_to_closed(self):
        print(f"[Circuit {self.name}] {self.state.value} -> CLOSED")
        self.state = CircuitState.CLOSED
        self.failure_count = 0
        self.success_count = 0

    def get_state(self) -> dict:
        with self.lock:
            return {
                "name": self.name,
                "state": self.state.value,
                "failure_count": self.failure_count,
                "success_count": self.success_count,
                "last_failure_time": self.last_failure_time,
            }

def circuit_breaker(circuit_name: str, config: CircuitBreakerConfig = None):
    breaker = CircuitBreaker(circuit_name, config)
    def decorator(func: Callable) -> Callable:
        @functools.wraps(func)
        def wrapper(*args, **kwargs):
            return breaker.call(func, *args, **kwargs)
        wrapper.circuit_breaker = breaker
        return wrapper
    return decorator

Tools and Libraries

Language	Library	Features
Java	Resilience4j	Circuit breaker, retry, rate limiter
.NET	Polly	Circuit breaker, retry, bulkhead
Python	pybreaker	Circuit breaker implementation
Go	gobreaker	Circuit breaker pattern
Node.js	opossum	Circuit breaker for Node.js
Ruby	breaker_machines	Modern circuit breaker

AWS Lambda Considerations

For serverless architectures, the circuit breaker pattern must be adapted for the ephemeral, stateless nature of functions:

def lambda_handler(event, context):
    try:
        result = call_external_service()
        return {"statusCode": 200, "body": result}
    except CircuitBreakerOpenError:
        return {"statusCode": 200, "body": get_fallback_data()}
    except Exception as e:
        logger.error(f"Error: {str(e)}")
        return {"statusCode": 500, "body": "Internal error"}

Resources

Resilience4j Documentation — Modern Java resilience library
Polly Documentation — .NET resilience and transient-fault-handling library
AWS Prescriptive Guidance: Circuit Breaker Pattern — Cloud implementation patterns
Martin Fowler: Circuit Breaker — Original pattern description
Microsoft: Implement Circuit Breaker Pattern — .NET implementation guide

Circuit Breaker Pattern: Building Resilient Microservices

Introduction

How Circuit Breakers Work

State Transitions

Core Concepts

Failure Threshold

Sliding Window

Timeout and Recovery

Implementation Examples

Java with Resilience4j

.NET with Polly

Go Implementation

Best Practices

1. Configure Thresholds Based on Traffic Patterns

2. Implement Fallback Strategies

3. Monitor Circuit Breaker State

4. Use Different Timeouts for Different Failure Types

5. Combine with Retry and Timeout Policies

Common Pitfalls

1. Setting Thresholds Too Low

2. Not Handling Circuit Open State

4. Ignoring Slow Calls

Service Mesh Integration

Istio Circuit Breaker

Testing Circuit Breakers

Unit Testing

Integration Testing with Chaos Engineering

Python Implementation

Tools and Libraries

AWS Lambda Considerations

Resources

Comments

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Introduction

How Circuit Breakers Work

State Transitions

Core Concepts

Failure Threshold

Sliding Window

Timeout and Recovery

Implementation Examples

Java with Resilience4j

.NET with Polly

Go Implementation

Best Practices

1. Configure Thresholds Based on Traffic Patterns

2. Implement Fallback Strategies

3. Monitor Circuit Breaker State

4. Use Different Timeouts for Different Failure Types

5. Combine with Retry and Timeout Policies

Common Pitfalls

1. Setting Thresholds Too Low

2. Not Handling Circuit Open State

3. Sharing Circuit Breakers Across Different Endpoints

4. Ignoring Slow Calls

Service Mesh Integration

Istio Circuit Breaker

Testing Circuit Breakers

Unit Testing

Integration Testing with Chaos Engineering

Python Implementation

Tools and Libraries

AWS Lambda Considerations

Resources

Comments

Share this article

👍 Was this article helpful?