Allow explicit context for OpenTelemetry logs

package.json

@@ -46,6 +46,9 @@
   },
   "devDependencies": {
     "@eslint/js": "^10.0.1",
+    "@opentelemetry/context-async-hooks": "^2.7.1",
+    "@opentelemetry/sdk-logs": "^0.218.0",
+    "@opentelemetry/sdk-trace-base": "^2.7.1",
     "@types/json-stringify-safe": "^5.0.3",
     "@types/jsonwebtoken": "^9.0.10",
     "@types/node": "^25.6.0",
@@ -75,6 +78,7 @@
     "README.md"
   ],
   "dependencies": {
+    "@opentelemetry/api": "^1.9.1",
     "@opentelemetry/api-logs": "^0.218.0",
     "ajv": "^8.18.0",
     "json-stringify-safe": "^5.0.1",

src/lib/plugins/otelOutput.ts

@@ -1,20 +1,25 @@
-
+import type { Context } from '@opentelemetry/api'
 import { logs as logsAPI, Logger, LoggerProvider, SeverityNumber, LogAttributes} from '@opentelemetry/api-logs'
 import { OutputPlugin } from './interfaces.js'
 import { Record, RecordType } from '../logger/record.js'
 import { Level } from '../logger/level.js'
 
+export type OpenTelemetryLogContextResolver = (record: Record) => Context | undefined
+export type OpenTelemetryLogContext = Context | OpenTelemetryLogContextResolver
+
 export class OpenTelemetryLogsOutputPlugin implements OutputPlugin {
     private logger: Logger
     private includeFieldsAsAttributes: FieldInclusionMode
+    private context?: OpenTelemetryLogContext
 
-    public constructor(loggerProvider?: LoggerProvider) {
+    public constructor(loggerProvider?: LoggerProvider, context?: OpenTelemetryLogContext) {
         if (loggerProvider) {
             this.logger = loggerProvider.getLogger('default')
         } else {
             this.logger = logsAPI.getLoggerProvider().getLogger("default")
         }
         this.includeFieldsAsAttributes = FieldInclusionMode.CustomFieldsOnly
+        this.context = context
     }
 
     public setIncludeFieldsAsAttributes(includeFieldsAsAttributes: FieldInclusionMode) {
@@ -31,15 +36,24 @@ export class OpenTelemetryLogsOutputPlugin implements OutputPlugin {
         this.populateAdditionalAttributes(record, attributes)
 
         const severityNumber = this.mapLevelToSeverityNumber(record.metadata.level)
+        const context = this.resolveContext(record)
 
         this.logger.emit({
             severityNumber: severityNumber,
             severityText: SeverityNumber[severityNumber],
             body: record.metadata.message,
-            attributes: attributes
+            attributes: attributes,
+            ...(context && { context })
         })
     }
 
+    private resolveContext(record: Record): Context | undefined {
+        if (typeof this.context === 'function') {
+            return this.context(record)
+        }
+        return this.context
+    }
+
     private mapLevelToSeverityNumber(level: Level): SeverityNumber {
         switch (level) {
             case Level.Error: