From 81b0bab6be05fb6ba0debf1cdf2f9534c0fa01fd Mon Sep 17 00:00:00 2001
From: Millicent Achieng <achieng.milli@gmail.com>
Date: Mon, 24 May 2021 11:45:11 +0300
Subject: [PATCH] Enable autocollection of unhandled exceptions (#963)

---
 src/telemetry/error-types.ts |  1 +
 src/telemetry/filters.ts     | 67 ++++++++++++++++++++++++++----------
 src/telemetry/telemetry.ts   |  4 ++-
 3 files changed, 53 insertions(+), 19 deletions(-)

diff --git a/src/telemetry/error-types.ts b/src/telemetry/error-types.ts
index 561083a09..c66a64b27 100644
--- a/src/telemetry/error-types.ts
+++ b/src/telemetry/error-types.ts
@@ -4,3 +4,4 @@ export const NETWORK_ERROR = 'NETWORK_ERROR';
 export const LINK_ERROR = 'LINK_ERROR';
 export const COMPONENT_ERROR = 'COMPONENT_ERROR';
 export const OPERATIONAL_ERROR = 'OPERATIONAL_ERROR';
+export const UNHANDLED_ERROR = 'UNHANDLED_ERROR';
diff --git a/src/telemetry/filters.ts b/src/telemetry/filters.ts
index c1ce84db5..7f13d9335 100644
--- a/src/telemetry/filters.ts
+++ b/src/telemetry/filters.ts
@@ -1,4 +1,6 @@
 import { ITelemetryItem } from '@microsoft/applicationinsights-web';
+import { exception } from 'console';
+import { errorTypes } from '.';
 import {
   DEVX_API_URL,
   GRAPH_API_SANDBOX_URL,
@@ -23,26 +25,25 @@ export function filterTelemetryTypes(envelope: ITelemetryItem) {
 }
 
 export function filterRemoteDependencyData(envelope: ITelemetryItem): boolean {
-  const baseData = envelope.baseData || {};
-  if (envelope.baseType !== 'RemoteDependencyData') {
-    return true;
-  }
+  if (envelope.baseType === 'RemoteDependencyData') {
+    const baseData = envelope.baseData || {};
+    const urlObject = new URL(baseData.target || '');
 
-  const targetsToInclude = [GRAPH_URL, DEVX_API_URL, GRAPH_API_SANDBOX_URL];
-  const urlObject = new URL(baseData.target || '');
-  if (!targetsToInclude.includes(urlObject.origin)) {
-    return false;
-  }
+    const targetsToInclude = [GRAPH_URL, DEVX_API_URL, GRAPH_API_SANDBOX_URL];
+    if (!targetsToInclude.includes(urlObject.origin)) {
+      return false;
+    }
 
-  const target = baseData.target || '';
-  switch (urlObject.origin) {
-    case GRAPH_URL:
-      baseData.name = sanitizeQueryUrl(target);
-      break;
-    case GRAPH_API_SANDBOX_URL:
-      baseData.name = sanitizeGraphAPISandboxUrl(target);
-    default:
-      break;
+    const target = baseData.target || '';
+    switch (urlObject.origin) {
+      case GRAPH_URL:
+        baseData.name = sanitizeQueryUrl(target);
+        break;
+      case GRAPH_API_SANDBOX_URL:
+        baseData.name = sanitizeGraphAPISandboxUrl(target);
+      default:
+        break;
+    }
   }
   return true;
 }
@@ -73,3 +74,33 @@ export function sanitizeTelemetryItemUriProperty(envelope: ITelemetryItem) {
   }
   return true;
 }
+
+export function sanitizeStackTrace(envelope: ITelemetryItem) {
+  if (envelope.baseType === 'ExceptionData') {
+    const telemetryItem = envelope.baseData || {};
+    telemetryItem.properties = telemetryItem.properties || {};
+
+    if (telemetryItem.exceptions && telemetryItem.exceptions.length > 0) {
+      const exception = telemetryItem.exceptions[0];
+      const parsedStack = exception.parsedStack[0];
+
+      // Only capture errors coming from our source code and not dependencies, to reduce noise
+      if (!parsedStack.fileName.startsWith('webpack-internal')) {
+        return false;
+      }
+
+      // Add properties for unhandled exceptions only
+      if (!telemetryItem.properties.ComponentName) {
+        telemetryItem.properties.ComponentName = parsedStack.assembly;
+        telemetryItem.properties.Message = exception.stack.split('\n')[0]; // Read first line only
+        exception.message = errorTypes.UNHANDLED_ERROR;
+      }
+
+      exception.hasFullStack = false;
+      exception.stack = null;
+      exception.parsedStack = [parsedStack];
+      telemetryItem.exceptions = [exception];
+    }
+  }
+  return true;
+}
diff --git a/src/telemetry/telemetry.ts b/src/telemetry/telemetry.ts
index 9b978c1a7..20f3f12a6 100644
--- a/src/telemetry/telemetry.ts
+++ b/src/telemetry/telemetry.ts
@@ -18,6 +18,7 @@ import {
   addCommonTelemetryItemProperties,
   filterRemoteDependencyData,
   filterTelemetryTypes,
+  sanitizeStackTrace,
   sanitizeTelemetryItemUriProperty,
 } from './filters';
 import ITelemetry from './ITelemetry';
@@ -32,7 +33,7 @@ class Telemetry implements ITelemetry {
 
     this.config = {
       instrumentationKey: this.getInstrumentationKey(),
-      disableExceptionTracking: true,
+      disableExceptionTracking: false, // Enables autocollection of uncaught exceptions. Used with `sanitizeStackTrace` telemetry initializer to remove any data that might be PII.
       disableAjaxTracking: true,
       disableFetchTracking: false, // Enables capturing of telemetry data for outgoing requests. Used with `filterRemoteDependencyData` telemetry initializer to sanitize captured data to prevent inadvertent capture of PII.
       disableTelemetry: this.getInstrumentationKey() ? false : true,
@@ -49,6 +50,7 @@ class Telemetry implements ITelemetry {
     this.appInsights.trackPageView();
     this.appInsights.addTelemetryInitializer(filterTelemetryTypes);
     this.appInsights.addTelemetryInitializer(filterRemoteDependencyData);
+    this.appInsights.addTelemetryInitializer(sanitizeStackTrace);
     this.appInsights.addTelemetryInitializer(sanitizeTelemetryItemUriProperty);
     this.appInsights.addTelemetryInitializer(addCommonTelemetryItemProperties);
     this.appInsights.context.application.ver = version;