feat(node-sdk): make config optional (open-telemetry#331)

* feat(node-sdk): make config optional

closes open-telemetry#330

Signed-off-by: Olivier Albertini <[email protected]>

Author: OlivierAlbertini

packages/opentelemetry-node-sdk/src/NodeTracer.ts

@@ -28,12 +28,12 @@ export class NodeTracer extends BasicTracer {
   /**
    * Constructs a new Tracer instance.
    */
-  constructor(config: NodeTracerConfig) {
+  constructor(config: NodeTracerConfig = {}) {
     if (config.scopeManager === undefined) {
       config.scopeManager = new AsyncHooksScopeManager();
       config.scopeManager.enable();
     }
-    super(Object.assign({}, { scopeManager: config.scopeManager }, config));
+    super(Object.assign({ scopeManager: config.scopeManager }, config));
 
     this._pluginLoader = new PluginLoader(this, this.logger);
     this._pluginLoader.load(config.plugins || DEFAULT_INSTRUMENTATION_PLUGINS);

packages/opentelemetry-node-sdk/test/NodeTracer.test.ts

@@ -53,7 +53,7 @@ describe('NodeTracer', () => {
 
   describe('constructor', () => {
     it('should construct an instance with required only options', () => {
-      tracer = new NodeTracer({});
+      tracer = new NodeTracer();
       assert.ok(tracer instanceof NodeTracer);
     });