feat(instrumentation-mongodb): Lighten scrubbed data

Author: onurtemizkan

plugins/node/opentelemetry-instrumentation-mongodb/src/instrumentation.ts

@@ -55,6 +55,25 @@ import { V4Connect, V4Session } from './internal-types';
 import { PACKAGE_NAME, PACKAGE_VERSION } from './version';
 import { UpDownCounter } from '@opentelemetry/api';
 
+// Skipping mongoose-added `non-enumerable` properties
+// https://github.com/Automattic/mongoose/blob/b34aba65bd64540e330665477f542eb79c877909/lib/helpers/document/compile.js#L217C11-L228C6
+// These properties are added by mongoose and supposed to be non-enumerable
+// but they are enumerable in some versions of mongoose.
+// These properties have made non-enumerable from [email protected]
+// https://github.com/Automattic/mongoose/commit/62b7b9c07ad3c763d5e42714ee149c28412db79e
+const KEYS_TO_SKIP_SCRUBBING = [
+  'isNew',
+  '$__',
+  '$errors',
+  'errors',
+  '_doc',
+  '$locals',
+  '$op',
+  '__parentArray',
+  '__index',
+  '$isDocumentArrayElement',
+];
+
 /** mongodb instrumentation plugin for OpenTelemetry */
 export class MongoDBInstrumentation extends InstrumentationBase<MongoDBInstrumentationConfig> {
   private _connectionsUsage!: UpDownCounter;
@@ -932,17 +951,29 @@ export class MongoDBInstrumentation extends InstrumentationBase<MongoDBInstrumen
     return JSON.stringify(resultObj);
   }
 
-  private _scrubStatement(value: unknown): unknown {
+  private _scrubStatement(value: unknown, depth = 0): unknown {
+    if (depth >= 10) {
+      return 'Max Depth';
+    }
+
+    if (value instanceof Uint8Array || value instanceof Buffer) {
+      return 'Binary Data';
+    }
+
     if (Array.isArray(value)) {
-      return value.map(element => this._scrubStatement(element));
+      return value.map(element => this._scrubStatement(element, depth + 1));
     }
 
     if (typeof value === 'object' && value !== null) {
       return Object.fromEntries(
-        Object.entries(value).map(([key, element]) => [
-          key,
-          this._scrubStatement(element),
-        ])
+        Object.entries(value)
+          .filter(([key]) => {
+            return !KEYS_TO_SKIP_SCRUBBING.includes(key);
+          })
+          .map(([key, element]) => [
+            key,
+            this._scrubStatement(element, depth + 1),
+          ])
       );
     }
 

plugins/node/opentelemetry-instrumentation-mongodb/test/mongodb-v5-v6.test.ts

@@ -415,6 +415,81 @@ describe('MongoDBInstrumentation-Tracing-v5', () => {
           });
       });
     });
+
+    it('should skip `Buffer` and `Uint8Array` values', done => {
+      const buffer = Buffer.from('buffer');
+      const uint8Array = new Uint8Array([1, 2, 3, 4]);
+      const span = trace.getTracer('default').startSpan('insertRootSpan');
+      context.with(trace.setSpan(context.active(), span), () => {
+        collection
+          .insertOne({ buffer, uint8Array })
+          .then(() => {
+            span.end();
+            const spans = getTestSpans();
+            const operationName = 'mongodb.insert';
+            assertSpans(
+              spans,
+              operationName,
+              SpanKind.CLIENT,
+              'insert',
+              URL,
+              false,
+              false
+            );
+            const mongoSpan = spans.find(s => s.name === operationName);
+            const dbStatement = JSON.parse(
+              mongoSpan!.attributes[SEMATTRS_DB_STATEMENT] as string
+            );
+            assert.strictEqual(dbStatement.buffer, 'Binary Data');
+            assert.strictEqual(dbStatement.uint8Array, 'Binary Data');
+            done();
+          })
+          .catch(err => {
+            done(err);
+          });
+      });
+    });
+
+    it('should skip nested levels of objects over the limit of 10', done => {
+      const deeplyNestedObject = {
+        a: {
+          b: { c: { d: { e: { f: { g: { h: { i: { j: { k: 1 } } } } } } } } },
+        },
+      };
+
+      const span = trace.getTracer('default').startSpan('insertRootSpan');
+      context.with(trace.setSpan(context.active(), span), () => {
+        collection
+          .insertOne({ deeplyNestedObject })
+          .then(() => {
+            span.end();
+            const spans = getTestSpans();
+            const operationName = 'mongodb.insert';
+            assertSpans(
+              spans,
+              operationName,
+              SpanKind.CLIENT,
+              'insert',
+              URL,
+              false,
+              false
+            );
+            const mongoSpan = spans.find(s => s.name === operationName);
+            const dbStatement = JSON.parse(
+              mongoSpan!.attributes[SEMATTRS_DB_STATEMENT] as string
+            );
+            assert.deepStrictEqual(dbStatement.deeplyNestedObject, {
+              a: {
+                b: { c: { d: { e: { f: { g: { h: { i: 'Max Depth' } } } } } } },
+              },
+            });
+            done();
+          })
+          .catch(err => {
+            done(err);
+          });
+      });
+    });
   });
 
   describe('when specifying a dbStatementSerializer configuration', () => {