feat: add custom method toJSON for _LocalStream (#70)

* feat: add custom toJSON for _LocalStream
---------

Co-authored-by: Anna Tsukanova <[email protected]>

src/media/local-stream.spec.ts

@@ -4,7 +4,7 @@ import { LocalStream, LocalStreamEventNames, TrackEffect } from './local-stream'
 import { StreamEventNames } from './stream';
 
 /**
- * A dummy LocalStream implementation so we can instantiate it for testing.
+ * A dummy LocalStream implementation, so we can instantiate it for testing.
  */
 class TestLocalStream extends LocalStream {}
 
@@ -186,4 +186,29 @@ describe('LocalStream', () => {
       expect(emitSpy).toHaveBeenCalledTimes(0);
     });
   });
+
+  describe('toJSON', () => {
+    it('should correctly serialize data', () => {
+      expect.assertions(1);
+
+      const testLocalStream = new TestLocalStream(mockStream);
+      const jsonLocalStream = localStream.toJSON();
+      const jsonTestLocalStream = testLocalStream.toJSON();
+
+      expect(JSON.stringify(jsonLocalStream)).toStrictEqual(JSON.stringify(jsonTestLocalStream));
+    });
+
+    it('should return an object with inputStream, outputStream and effects properties', () => {
+      expect.assertions(6);
+
+      const jsonLocalStream = localStream.toJSON();
+
+      expect(jsonLocalStream).toHaveProperty('muted');
+      expect(jsonLocalStream).toHaveProperty('label');
+      expect(jsonLocalStream).toHaveProperty('readyState');
+      expect(jsonLocalStream).toHaveProperty('inputStream');
+      expect(jsonLocalStream).toHaveProperty('outputStream');
+      expect(jsonLocalStream).toHaveProperty('effects');
+    });
+  });
 });

src/media/local-stream.ts

@@ -283,6 +283,37 @@ abstract class _LocalStream extends Stream {
     return this.effects;
   }
 
+  /**
+   * Method to serialize data about input, output streams
+   * and also effects from LocalStream.
+   *
+   * @returns - A JSON-compatible object representation with data from LocalStream.
+   */
+  toJSON() {
+    return {
+      muted: this.muted,
+      label: this.label,
+      readyState: this.readyState,
+      inputStream: {
+        active: this.inputStream.active,
+        id: this.inputStream.id,
+        enabled: this.inputTrack.enabled,
+        muted: this.inputTrack.muted,
+      },
+      outputStream: {
+        active: this.outputStream.active,
+        id: this.outputStream.id,
+      },
+      effects: this.effects.map((effect) => {
+        return {
+          id: effect.id,
+          kind: effect.kind,
+          isEnabled: effect.isEnabled,
+        };
+      }),
+    };
+  }
+
   /**
    * Cleanup the local effects.
    */