Fix #22. Improve error handling (#27)

* Fix pause method referrence in loaded latency engine

* Expose onError method

* Add error logging to example

* Bump dev deps

README.md

@@ -72,11 +72,12 @@ new SpeedTest({ configOptions })
 | <b>restart()</b> | Clears the current results and restarts the measurements from the beginning. |
 
 ### Notification Events
-| Event Method | Arguments | Description |
-| --- | --- | :--: |
-| <b>onRunningChange</b> | running: <i>boolean</i> | Invoked whenever the test engine starts or stops. The current state is included as a function argument. |
-| <b>onResultsChange</b> | { type: <i>string</i> } | Invoked whenever any item changes in the results, usually indicating the completion of a measurement. The type of measurement that changed is included as an info attribute in the function argument. |
-| <b>onFinish</b> | results: <i>[Results](#results-object)</i> | Invoked whenever the test engine finishes all the measurements. The final [results object](#results-object) is included as a function argument. |
+| Event Method           | Arguments                                  | Description |
+|------------------------|--------------------------------------------| :--: |
+| <b>onRunningChange</b> | running: <i>boolean</i>                    | Invoked whenever the test engine starts or stops. The current state is included as a function argument. |
+| <b>onResultsChange</b> | { type: <i>string</i> }                    | Invoked whenever any item changes in the results, usually indicating the completion of a measurement. The type of measurement that changed is included as an info attribute in the function argument. |
+| <b>onFinish</b>        | results: <i>[Results](#results-object)</i> | Invoked whenever the test engine finishes all the measurements. The final [results object](#results-object) is included as a function argument. |
+| <b>onError</b>         | error: <i>string</i>                       | Invoked whenever an error occurs during one of the measurements. The error details are included as a function argument. |
 
 ### Measurement config
 The specific measurements to be performed by the test engine (and their sequence) can be customized using the `measurements` config option. This should be an array of objects, each with a `type` field, plus additional fields specific to that measurement type.

example/basic-page/index.html

@@ -22,6 +22,8 @@
       console.log(results.getScores());
     };
 
+    engine.onError = (e) => console.log(e);
+
     const playButton = document.createElement('button');
     playButton.textContent = "Start Speed Measurement";
     playButton.onclick = () => engine.play();

package.json

@@ -48,22 +48,22 @@
     "lodash.memoize": "^4.1.2"
   },
   "devDependencies": {
-    "@babel/core": "^7.22.5",
-    "@babel/preset-env": "^7.22.5",
+    "@babel/core": "^7.22.17",
+    "@babel/preset-env": "^7.22.15",
     "@rollup/plugin-babel": "^6.0.3",
-    "@rollup/plugin-node-resolve": "^15.1.0",
-    "eslint": "^8.43.0",
-    "eslint-plugin-compat": "^4.1.4",
-    "eslint-plugin-import": "^2.27.5",
+    "@rollup/plugin-node-resolve": "^15.2.1",
+    "eslint": "^8.49.0",
+    "eslint-plugin-compat": "^4.2.0",
+    "eslint-plugin-import": "^2.28.1",
     "eslint-plugin-json": "^3.1.0",
-    "eslint-plugin-prettier": "^4.2.1",
+    "eslint-plugin-prettier": "^5.0.0",
     "husky": "^8.0.3",
-    "lint-staged": "^13.2.2",
-    "prettier": "^2.8.8",
+    "lint-staged": "^14.0.1",
+    "prettier": "^3.0.3",
     "rimraf": "^5.0.1",
-    "rollup": "^3.25.1",
-    "rollup-plugin-dts": "^5.3.0",
-    "typescript": "^5.1.3"
+    "rollup": "^3.29.1",
+    "rollup-plugin-dts": "^6.0.2",
+    "typescript": "^5.2.2"
   },
   "engines": {
     "node": ">=12"

src/engines/BandwidthEngine/ParallelLatency.js

@@ -41,7 +41,7 @@ class BandwidthWithParallelLatencyEngine extends BandwidthEngine {
       };
 
       super.onRunningChange = this.#setLatencyRunning;
-      super.onConnectionError = () => this.#latencyEngine.stop();
+      super.onConnectionError = () => this.#latencyEngine.pause();
     }
   }
 
@@ -75,7 +75,7 @@ class BandwidthWithParallelLatencyEngine extends BandwidthEngine {
 
   set onConnectionError(onConnectionError) {
     super.onConnectionError = (...args) => {
-      this.#latencyEngine && this.#latencyEngine.stop();
+      this.#latencyEngine && this.#latencyEngine.pause();
       onConnectionError(...args);
     };
   }

src/index.d.ts

@@ -113,6 +113,7 @@ declare class SpeedTestEngine {
   onRunningChange: (running: boolean) => void;
   onResultsChange: ({ type: string }) => void;
   onFinish: (results: Results) => void;
+  onError: (error: string) => void;
 }
 
 export default SpeedTestEngine;

src/index.js

@@ -45,6 +45,11 @@ class MeasurementEngine {
     this.#onFinish = f;
   }
 
+  #onError = () => {}; // callback invoked if an error occurs during measurement
+  set onError(f) {
+    this.#onError = f;
+  }
+
   // Public methods
   pause() {
     pausableTypes.includes(this.#curType()) && this.#curEngine.pause();
@@ -266,12 +271,16 @@ class MeasurementEngine {
         engine.onConnectionError = e => {
           msmResults.error = e;
           this.onResultsChange({ type });
+          this.#onError(`Connection error while measuring packet loss: ${e}`);
           this.#next();
         };
 
         engine.onCredentialsFailure = () => {
           msmResults.error = 'unable to get turn server credentials';
           this.onResultsChange({ type });
+          this.#onError(
+            'Error while measuring packet loss: unable to get turn server credentials.'
+          );
           this.#next();
         };
 
@@ -326,6 +335,7 @@ class MeasurementEngine {
         engine.onConnectionError = e => {
           msmResults.error = e;
           this.onResultsChange({ type });
+          this.#onError(`Connection error while measuring latency: ${e}`);
           this.#next();
         };
 
@@ -438,6 +448,7 @@ class MeasurementEngine {
           engine.onConnectionError = e => {
             msmResults.error = e;
             this.onResultsChange({ type });
+            this.#onError(`Connection error while measuring ${type}: ${e}`);
             this.#next();
           };