feat: Implement CircuitBreakerPolicy

Closes #193.

package.json

@@ -41,18 +41,20 @@
   "devDependencies": {
     "@commitlint/cli": "^8.3.5",
     "@commitlint/travis-cli": "^8.3.5",
+    "@diplomatiq/eslint-config-tslib": "^2.5.0",
     "@types/chai": "^4.2.11",
     "@types/mocha": "^7.0.2",
     "@types/node": "^13.9.2",
+    "@types/sinon": "^7.5.2",
     "chai": "^4.2.0",
     "conventional-changelog-cli": "^2.0.31",
     "cross-env": "^7.0.2",
-    "@diplomatiq/eslint-config-tslib": "^2.5.0",
     "esm": "^3.2.25",
     "husky": "^4.2.3",
     "mocha": "^7.1.1",
     "nyc": "^15.0.0",
     "prettier": "^1.19.1",
+    "sinon": "^9.0.1",
     "source-map-support": "^0.5.16",
     "ts-node": "^8.8.1",
     "typescript": "^3.8.3"

src/main.ts

@@ -1,6 +1,26 @@
+export { RandomGenerator } from './interfaces/randomGenerator';
+export { Policy } from './policies/policy';
+export { ProactivePolicy } from './policies/proactive/proactivePolicy';
+export { ExecutionException } from './policies/proactive/timeoutPolicy/executionException';
+export { OnTimeoutFn } from './policies/proactive/timeoutPolicy/onTimeoutFn';
 export { TimeoutException } from './policies/proactive/timeoutPolicy/timeoutException';
 export { TimeoutPolicy } from './policies/proactive/timeoutPolicy/timeoutPolicy';
+export { BrokenCircuitException } from './policies/reactive/circuitBreakerPolicy/brokenCircuitException';
+export { CircuitBreakerPolicy } from './policies/reactive/circuitBreakerPolicy/circuitBreakerPolicy';
+export { CircuitState } from './policies/reactive/circuitBreakerPolicy/circuitState';
+export { IsolatedCircuitException } from './policies/reactive/circuitBreakerPolicy/isolatedCircuitException';
+export { OnAttemptingCloseFn } from './policies/reactive/circuitBreakerPolicy/onAttemptingCloseFn';
+export { OnCloseFn } from './policies/reactive/circuitBreakerPolicy/onCloseFn';
+export { OnIsolateFn } from './policies/reactive/circuitBreakerPolicy/onIsolateFn';
+export { OnOpenFn } from './policies/reactive/circuitBreakerPolicy/onOpenFn';
 export { FallbackChainExhaustedException } from './policies/reactive/fallbackPolicy/fallbackChainExhaustedException';
+export { FallbackChainLink } from './policies/reactive/fallbackPolicy/fallbackChainLink';
 export { FallbackPolicy } from './policies/reactive/fallbackPolicy/fallbackPolicy';
+export { OnFallbackFn } from './policies/reactive/fallbackPolicy/onFallbackFn';
+export { ReactivePolicy } from './policies/reactive/reactivePolicy';
+export { BackoffStrategy } from './policies/reactive/retryPolicy/backoffStrategy';
 export { BackoffStrategyFactory } from './policies/reactive/retryPolicy/backoffStrategyFactory';
+export { OnRetryFn } from './policies/reactive/retryPolicy/onRetryFn';
 export { RetryPolicy } from './policies/reactive/retryPolicy/retryPolicy';
+export { OnFinallyFn } from './types/onFinallyFn';
+export { Predicate } from './types/predicate';

src/policies/proactive/timeoutPolicy/onTimeoutFn.ts

@@ -0,0 +1 @@
+export type OnTimeoutFn = (timedOutAfter: number) => void | Promise<void>;

src/policies/proactive/timeoutPolicy/timeoutPolicy.ts

@@ -1,15 +1,13 @@
 import { ProactivePolicy } from '../proactivePolicy';
 import { ExecutionException } from './executionException';
+import { OnTimeoutFn } from './onTimeoutFn';
 import { TimeoutException } from './timeoutException';
 
 export class TimeoutPolicy<ResultType> extends ProactivePolicy<ResultType> {
     private timeoutMs: number | undefined;
-    private readonly onTimeoutFns: Array<(timedOutAfter: number) => void | Promise<void>> = [];
-    private executing = 0;
+    private readonly onTimeoutFns: OnTimeoutFn[] = [];
 
-    public constructor() {
-        super();
-    }
+    private executing = 0;
 
     public timeoutAfter(timeoutMs: number): void {
         if (!Number.isInteger(timeoutMs)) {

src/policies/reactive/circuitBreakerPolicy/brokenCircuitException.ts

@@ -0,0 +1 @@
+export class BrokenCircuitException extends Error {}