feat: Add additional fields collected by the TraceKit package for sta…

…ck traces (#383)

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## Short description of the changes

Introduces the [TraceKit](https://github.com/csnover/TraceKit) package
to the web distro. Adds additional fields with the help of the
`TraceKit` package. These additional fields are prefixed with
`exception.structured_stacktrace`. Additional fields will be sent by
`GlobalErrorsInstrumentation`.

## How to verify that this has the expected result
I tested locally using the `hello-world-web` example provided by the
web-distro. Made the example to throw a simple error. This was the
result I received on Honeycomb:

<img width="848" alt="Screenshot 2024-11-07 at 3 34 27 PM"
src="https://github.com/user-attachments/assets/ac6cc8ac-2cf6-47e5-b4fa-4d21d466c160">

Big thanks to @pkanal for helping with this change!

packages/honeycomb-opentelemetry-web/package.json

@@ -86,6 +86,7 @@
     "@opentelemetry/sdk-trace-web": "~1.27.0",
     "@opentelemetry/semantic-conventions": "~1.27.0",
     "shimmer": "^1.2.1",
+    "tracekit": "^0.4.7",
     "ua-parser-js": "^1.0.37",
     "web-vitals": "^4.2.3"
   }

packages/honeycomb-opentelemetry-web/src/global-errors-autoinstrumentation.ts

@@ -7,6 +7,7 @@ import {
   SEMATTRS_EXCEPTION_STACKTRACE,
   SEMATTRS_EXCEPTION_TYPE,
 } from '@opentelemetry/semantic-conventions';
+import { computeStackTrace, StackFrame } from 'tracekit';
 
 export interface GlobalErrorsInstrumentationConfig
   extends InstrumentationConfig {}
@@ -26,6 +27,34 @@ export class GlobalErrorsInstrumentation extends InstrumentationAbstract {
     this._isEnabled = enabled;
   }
 
+  _computeStackTrace = (error: Error | undefined) => {
+    if (!error) {
+      return {};
+    }
+
+    // OTLP does not accept arrays of objects
+    // breaking down the stack into arrays of strings/numbers
+    const structuredStack: StackFrame[] = computeStackTrace(error).stack;
+    const lines: number[] = [];
+    const columns: number[] = [];
+    const functions: string[] = [];
+    const urls: string[] = [];
+
+    for (const stackFrame of structuredStack) {
+      lines.push(stackFrame.line);
+      columns.push(stackFrame.column);
+      functions.push(stackFrame.func);
+      urls.push(stackFrame.url);
+    }
+
+    return {
+      'exception.structured_stacktrace.columns': columns,
+      'exception.structured_stacktrace.lines': lines,
+      'exception.structured_stacktrace.functions': functions,
+      'exception.structured_stacktrace.urls': urls,
+    };
+  };
+
   onError = (event: ErrorEvent | PromiseRejectionEvent) => {
     const error: Error | undefined =
       'reason' in event ? event.reason : event.error;
@@ -35,6 +64,7 @@ export class GlobalErrorsInstrumentation extends InstrumentationAbstract {
       [SEMATTRS_EXCEPTION_TYPE]: type,
       [SEMATTRS_EXCEPTION_MESSAGE]: message,
       [SEMATTRS_EXCEPTION_STACKTRACE]: error?.stack,
+      ...this._computeStackTrace(error),
     };
     // otel spec requires at minimum these two
     if (!message || !type) return;

packages/honeycomb-opentelemetry-web/test/global-errors-instrumentation.test.ts

@@ -33,10 +33,15 @@ describe('Global Errors Instrumentation Tests', () => {
 
       const span = exporter.getFinishedSpans()[0];
       expect(span.name).toBe('exception');
+      // TODO: Mock a stack trace and test that it returns the correct keys and values
       expect(span.attributes).toMatchObject({
         'exception.type': 'Error',
         'exception.message': 'Something happened',
         'exception.stacktrace': expect.any(String),
+        'exception.structured_stacktrace.columns': expect.any(Array),
+        'exception.structured_stacktrace.lines': expect.any(Array),
+        'exception.structured_stacktrace.functions': expect.any(Array),
+        'exception.structured_stacktrace.urls': expect.any(Array),
       });
     });
 
@@ -60,4 +65,20 @@ describe('Global Errors Instrumentation Tests', () => {
       });
     });
   });
+
+  describe('_computeStackTrace', () => {
+    it('should return an empty object if error is undefined', () => {
+      expect(instr._computeStackTrace(undefined)).toEqual({});
+    });
+
+    // TODO: Mock a stack trace and test that it returns the correct keys and values
+    it('should return an object with structured stack trace information', () => {
+      expect(instr._computeStackTrace(new Error('This is an error'))).toEqual({
+        'exception.structured_stacktrace.columns': expect.any(Array),
+        'exception.structured_stacktrace.lines': expect.any(Array),
+        'exception.structured_stacktrace.functions': expect.any(Array),
+        'exception.structured_stacktrace.urls': expect.any(Array),
+      });
+    });
+  });
 });