fix(sdk): headers as an argument in initialization (#569)

Author: nirga

packages/traceloop-sdk/src/lib/interfaces/initialize-options.interface.ts

@@ -64,6 +64,11 @@ export interface InitializeOptions {
    */
   exporter?: SpanExporter;
 
+  /**
+   * The headers to be sent with the traces data. Optional.
+   */
+  headers?: Record<string, string>;
+
   /**
    * The OpenTelemetry SpanProcessor to be used for processing traces data. Optional.
    * Defaults to the BatchSpanProcessor.

packages/traceloop-sdk/src/lib/tracing/index.ts

@@ -261,9 +261,11 @@ export const startTracing = (options: InitializeOptions) => {
     });
   }
 
-  const headers = process.env.TRACELOOP_HEADERS
-    ? baggageUtils.parseKeyPairsIntoRecord(process.env.TRACELOOP_HEADERS)
-    : { Authorization: `Bearer ${options.apiKey}` };
+  const headers =
+    options.headers ||
+    (process.env.TRACELOOP_HEADERS
+      ? baggageUtils.parseKeyPairsIntoRecord(process.env.TRACELOOP_HEADERS)
+      : { Authorization: `Bearer ${options.apiKey}` });
 
   const traceExporter =
     options.exporter ??