Major refactory: improved resolver, remote and overall error handling (#202)

Author: petruki

src/client.d.ts

@@ -1,4 +1,5 @@
 import { Switcher } from './switcher';
+import { SwitcherResult } from './lib/result';
 
 /**
 * Quick start with the following 3 steps.
@@ -118,15 +119,6 @@ export class Client {
 
 }
 
-/**
- * ResultDetail is a detailed response from the API.
- */
-export type ResultDetail = {
-  result: boolean;
-  reason: string | undefined;
-  metadata: object | undefined;
-}
-
 /**
  * Criteria defines the condition(s) to evaluate the switcher when using Client.assume(key)
  */
@@ -149,7 +141,7 @@ export type Criteria = {
 export type LoggerRecord = {
   key: string;
   input: string[][];
-  response: ResultDetail
+  response: SwitcherResult
 }
 
 /**
@@ -303,5 +295,5 @@ declare class Key {
   /**
    * Return key response
    */
-  getResponse(input?: string[][]): ResultDetail;
+  getResponse(input?: string[][]): SwitcherResult;
 }

src/client.js

@@ -15,7 +15,7 @@ import {
 import TimedMatch from './lib/utils/timed-match/index.js';
 import ExecutionLogger from './lib/utils/executionLogger.js';
 import SnapshotAutoUpdater from './lib/utils/snapshotAutoUpdater.js';
-import { SnapshotNotFoundError } from './lib/exceptions/index.js';
+import { ClientError } from './lib/exceptions/index.js';
 import { loadDomain, validateSnapshot, checkSwitchersLocal } from './lib/snapshot.js';
 import { Switcher } from './switcher.js';
 import { Auth } from './lib/remoteAuth.js';
@@ -106,7 +106,7 @@ export class Client {
 
   static async checkSnapshot() {
     if (!GlobalSnapshot.snapshot) {
-      throw new SnapshotNotFoundError('Snapshot is not loaded. Use Client.loadSnapshot()');
+      throw new ClientError('Snapshot is not loaded. Use Client.loadSnapshot()');
     }
 
     if (Auth.isTokenExpired()) {
@@ -264,10 +264,4 @@ export class SwitcherOptions {
   static build() {
     return new SwitcherOptions();
   }
-}
-
-export class ResultDetail {
-  static build() {
-    return new ResultDetail();
-  }
 }

src/lib/bypasser/key.js

@@ -1,3 +1,4 @@
+import { SwitcherResult } from '../result.js';
 import Criteria from './criteria.js';
 
 /**
@@ -67,11 +68,7 @@ export default class Key {
             result = this.#getResultBasedOnCriteria(this.#criteria, input);
         }
 
-        return {
-            result,
-            reason: this.#reason,
-            metadata: this.#metadata,
-        };
+        return SwitcherResult.create(result, this.#reason, this.#metadata);
     }
 
     #getResultBasedOnCriteria(criteria, input) {

src/lib/exceptions/index.js

@@ -1,34 +1,20 @@
-export class AuthError extends Error {
-    constructor(message) {
-        super(`Something went wrong: ${message}`);
-        this.name = this.constructor.name;
-    }
+export class ClientError extends Error {
+  constructor(message) {
+    super(`Something went wrong: ${message}`);
+    this.name = this.constructor.name;
+  }
 }
 
-export class CriteriaError extends Error {
-    constructor(message) {
-        super(`Something went wrong: ${message}`);
-        this.name = this.constructor.name;
-    }
+export class RemoteError extends ClientError {
+  constructor(message) {
+    super(message);
+    this.name = this.constructor.name;
+  }
 }
 
-export class CheckSwitcherError extends Error {
-    constructor(notFound) {
-        super(`Something went wrong: [${notFound}] not found`);
-        this.name = this.constructor.name;
-    }
+export class CheckSwitcherError extends ClientError {
+  constructor(notFound) {
+    super(`[${notFound}] not found`);
+    this.name = this.constructor.name;
+  }
 }
-
-export class SnapshotServiceError extends Error {
-    constructor(message) {
-        super(`Something went wrong: ${message}`);
-        this.name = this.constructor.name;
-    }
-}
-
-export class SnapshotNotFoundError extends Error {
-    constructor(message) {
-      super(`Something went wrong: ${message}`);
-      this.name = this.constructor.name;
-    }
-}

src/lib/remote.js

@@ -1,15 +1,13 @@
 import fs from 'node:fs';
 import { Agent } from 'node:https';
 
-import { AuthError, CheckSwitcherError, CriteriaError, SnapshotServiceError } from './exceptions/index.js';
+import { CheckSwitcherError, ClientError, RemoteError } from './exceptions/index.js';
 import FetchFacade from './utils/fetchFacade.js';
 import * as util from './utils/index.js';
 import { GlobalAuth } from './globals/globalAuth.js';
 
 let httpClient;
 
-const getConnectivityError = (code) => `Connection has been refused - ${code}`;
-
 const getHeader = (token) => {
     return {
         'Authorization': `Bearer ${token}`,
@@ -19,7 +17,7 @@ const getHeader = (token) => {
 
 export function setCerts(certPath) {
     if (!fs.existsSync(certPath)) {
-        throw new Error(`Invalid certificate path '${certPath}'`);
+        throw new RemoteError(`Invalid certificate path '${certPath}'`);
     }
 
     httpClient = new Agent({
@@ -36,7 +34,7 @@ export function getEntry(input) {
         return undefined;
     }
 
-    let entry = [];
+    const entry = [];
     for (const inputValues of input) {
         entry.push({
             strategy: inputValues[0],
@@ -67,9 +65,9 @@ export async function auth(context) {
             return response.json();
         }
 
-        throw new Error(`[auth] failed with status ${response.status}`);
+        throw new RemoteError(`[auth] failed with status ${response.status}`);
     } catch (e) {
-        throw new AuthError(e.errno ? getConnectivityError(e.errno) : e.message);
+        throw errorHandler(e);
     }
 }
 
@@ -95,10 +93,10 @@ export async function checkCriteria(key, input, showDetail = false) {
         if (response.status == 200) {
             return response.json();
         }
-      
-        throw new Error(`[checkCriteria] failed with status ${response.status}`);
+        
+        throw new RemoteError(`[checkCriteria] failed with status ${response.status}`);
     } catch (e) {
-        throw new CriteriaError(e.errno ? getConnectivityError(e.errno) : e.message);
+        throw errorHandler(e);
     }
 }
 
@@ -112,15 +110,15 @@ export async function checkSwitchers(switcherKeys) {
         });
 
         if (response.status != 200) {
-            throw new Error(`[checkSwitchers] failed with status ${response.status}`);
+            throw new RemoteError(`[checkSwitchers] failed with status ${response.status}`);
         }
 
         const json = response.json();
         if (json.not_found.length) {
             throw new CheckSwitcherError(json.not_found);
         }
     } catch (e) {
-        throw new CriteriaError(e.errno ? getConnectivityError(e.errno) : e.message);
+        throw errorHandler(e);
     }
 }
 
@@ -136,9 +134,9 @@ export async function checkSnapshotVersion(version) {
             return response.json();
         }
 
-        throw new Error(`[checkSnapshotVersion] failed with status ${response.status}`);
+        throw new RemoteError(`[checkSnapshotVersion] failed with status ${response.status}`);
     } catch (e) {
-        throw new SnapshotServiceError(e.errno ? getConnectivityError(e.errno) : e.message);
+        throw errorHandler(e);
     }
 }
 
@@ -171,8 +169,16 @@ export async function resolveSnapshot(domain, environment, component) {
             return JSON.stringify(response.json(), null, 4);
         }
 
-        throw new Error(`[resolveSnapshot] failed with status ${response.status}`);
+        throw new RemoteError(`[resolveSnapshot] failed with status ${response.status}`);
     } catch (e) {
-        throw new SnapshotServiceError(e.errno ? getConnectivityError(e.errno) : e.message);
+        throw errorHandler(e);
     }
+}
+
+function errorHandler(e) {
+    if (!(e instanceof ClientError)) {
+        throw new RemoteError(e.errno ? `Connection has been refused - ${e.errno}` : e.message);
+    }
+
+    throw e;
 }