Master MCP Server

import { test } from 'node:test' import assert from 'node:assert' import { CircuitBreaker, InMemoryCircuitStorage } from '../../../src/routing/circuit-breaker.js' test('CircuitBreaker onSuccess in closed state should only reset failures', async () => { const storage = new InMemoryCircuitStorage() const breaker = new CircuitBreaker({ failureThreshold: 2, successThreshold: 2, recoveryTimeoutMs: 100, }, storage) const key = 'test-key' // Simulate some failures, but not enough to open the circuit breaker.onFailure(key) let record = storage.get(key) assert.strictEqual(record?.failures, 1, 'should have 1 failure') assert.strictEqual(record?.state, 'closed', 'should be in closed state') // Simulate a success breaker.onSuccess(key) record = storage.get(key) assert.strictEqual(record?.failures, 0, 'failures should be reset to 0') assert.strictEqual(record?.successes, 0, 'successes should remain 0') // This is the key check for the bug assert.strictEqual(record?.state, 'closed', 'should remain in closed state') }) test('CircuitBreaker should open after reaching failure threshold', async () => { const storage = new InMemoryCircuitStorage() const breaker = new CircuitBreaker({ failureThreshold: 2, successThreshold: 2, recoveryTimeoutMs: 100, }, storage) const key = 'test-key' breaker.onFailure(key) breaker.onFailure(key) const record = storage.get(key) assert.strictEqual(record?.state, 'open', 'should be in open state') assert.strictEqual(record?.failures, 2, 'should have 2 failures') }) test('CircuitBreaker should transition to half-open after recovery timeout', async () => { const storage = new InMemoryCircuitStorage() const breaker = new CircuitBreaker({ failureThreshold: 2, successThreshold: 2, recoveryTimeoutMs: 50, }, storage) const key = 'test-key' // Open the circuit breaker.onFailure(key) breaker.onFailure(key) // Wait for recovery timeout await new Promise(resolve => setTimeout(resolve, 60)) // First call should be allowed and move to half-open const gate = breaker.canExecute(key) assert.strictEqual(gate.allowed, true, 'execution should be allowed') const record = storage.get(key) assert.strictEqual(record?.state, 'half_open', 'should be in half-open state') }) test('CircuitBreaker should close after successes in half-open state', async () => { const storage = new InMemoryCircuitStorage() const breaker = new CircuitBreaker({ failureThreshold: 2, successThreshold: 2, recoveryTimeoutMs: 50, }, storage) const key = 'test-key' // Open the circuit breaker.onFailure(key) breaker.onFailure(key) // Wait for recovery timeout await new Promise(resolve => setTimeout(resolve, 60)) // Transition to half-open breaker.canExecute(key) // Succeed twice breaker.onSuccess(key) breaker.onSuccess(key) const record = storage.get(key) assert.strictEqual(record?.state, 'closed', 'should be in closed state') assert.strictEqual(record?.failures, 0, 'failures should be reset') assert.strictEqual(record?.successes, 0, 'successes should be reset') }) test('CircuitBreaker should re-open after failure in half-open state', async () => { const storage = new InMemoryCircuitStorage() const breaker = new CircuitBreaker({ failureThreshold: 2, successThreshold: 2, recoveryTimeoutMs: 50, }, storage) const key = 'test-key' // Open the circuit breaker.onFailure(key) breaker.onFailure(key) // Wait for recovery timeout await new Promise(resolve => setTimeout(resolve, 60)) // Transition to half-open breaker.canExecute(key) // Fail once breaker.onFailure(key) const record = storage.get(key) assert.strictEqual(record?.state, 'open', 'should be in open state again') })