private void doSerDeTest(String blobId, Map<String, String> metadata) throws Exception {
    String jsonString = SignedIdSerDe.toJson(blobId, metadata);
    // ensure that the string is valid json.
    new JSONObject(jsonString);
    assertEquals("Unexpected deserialized ID and metadata value", new Pair<>(blobId, metadata),
        SignedIdSerDe.fromJson(jsonString));
  }
Perform a test of serialization/deserialization with specific inputs.
@param blobId the blob ID to test with.
@param metadata the metadata to test with.
@throws Exception
ambry-frontend/src/test/java/com/github/ambry/frontend/SignedIdSerDeTest.java