feat: configure overloads

the user can call startActiveTracer with 2, 3 or 4 args, with the last being the function

Signed-off-by: naseemkullah <[email protected]>

src/trace/NoopTracer.ts

@@ -14,8 +14,9 @@
  * limitations under the License.
  */
 
-import { getSpanContext } from '../trace/context-utils';
+import { ContextAPI } from '../api/context';
 import { Context } from '../context/types';
+import { getSpanContext } from '../trace/context-utils';
 import { NonRecordingSpan } from './NonRecordingSpan';
 import { Span } from './span';
 import { isSpanContextValid } from './spancontext-utils';
@@ -48,12 +49,28 @@ export class NoopTracer implements Tracer {
 
   startActiveSpan<F extends (span: Span) => ReturnType<F>>(
     name: string,
-    options: SpanOptions,
-    context: Context,
-    fn: F
-  ) {
-    const span = this.startSpan(name, options, context);
-    return fn(span);
+    optionsOrFn: SpanOptions | F,
+    contextOrFn?: Context | F,
+    fn?: F
+  ): ReturnType<F> {
+    if (typeof optionsOrFn === 'function') {
+      const span = this.startSpan(
+        name,
+        undefined,
+        ContextAPI.getInstance().active()
+      );
+      return optionsOrFn(span);
+    } else if (typeof contextOrFn === 'function') {
+      const span = this.startSpan(
+        name,
+        optionsOrFn,
+        ContextAPI.getInstance().active()
+      );
+      return contextOrFn(span);
+    } else {
+      const span = this.startSpan(name, optionsOrFn, contextOrFn);
+      return fn!(span);
+    }
   }
 }
 

src/trace/ProxyTracer.ts

@@ -14,6 +14,7 @@
  * limitations under the License.
  */
 
+import { ContextAPI } from '../api/context';
 import { Context } from '../context/types';
 import { NOOP_TRACER } from './NoopTracer';
 import { ProxyTracerProvider } from './ProxyTracerProvider';
@@ -40,12 +41,28 @@ export class ProxyTracer implements Tracer {
 
   startActiveSpan<F extends (span: Span) => ReturnType<F>>(
     name: string,
-    options: SpanOptions,
-    context: Context,
-    fn: F
-  ) {
-    const span = this.startSpan(name, options, context);
-    return fn(span);
+    optionsOrFn: SpanOptions | F,
+    contextOrFn?: Context | F,
+    fn?: F
+  ): ReturnType<F> {
+    if (typeof optionsOrFn === 'function') {
+      const span = this.startSpan(
+        name,
+        undefined,
+        ContextAPI.getInstance().active()
+      );
+      return optionsOrFn(span);
+    } else if (typeof contextOrFn === 'function') {
+      const span = this.startSpan(
+        name,
+        optionsOrFn,
+        ContextAPI.getInstance().active()
+      );
+      return contextOrFn(span);
+    } else {
+      const span = this.startSpan(name, optionsOrFn, contextOrFn);
+      return fn!(span);
+    }
   }
 
   /**

src/trace/tracer.ts

@@ -52,16 +52,15 @@ export interface Tracer {
    *     span.end();
    *   });
    */
-  // todo: figure out overloading
-  // startActiveSpan?<F extends (span: Span) => ReturnType<F>>(
-  //   name: string,
-  //   fn: F
-  // ): ReturnType<F>;
-  // startActiveSpan?<F extends (span: Span) => ReturnType<F>>(
-  //   name: string,
-  //   options: SpanOptions,
-  //   fn: F
-  // ): ReturnType<F>;
+  startActiveSpan?<F extends (span: Span) => ReturnType<F>>(
+    name: string,
+    fn: F
+  ): ReturnType<F>;
+  startActiveSpan?<F extends (span: Span) => ReturnType<F>>(
+    name: string,
+    options: SpanOptions,
+    fn: F
+  ): ReturnType<F>;
   startActiveSpan?<F extends (span: Span) => ReturnType<F>>(
     name: string,
     options: SpanOptions,