tensorflow/models · error · ValueError

Invalid model instance: %s, it should be a %s

Error message

Invalid model instance: %s, it should be a %s

What it means

Error "Invalid model instance: %s, it should be a %s" thrown in tensorflow/models.

Source

Thrown at official/legacy/bert/serving.py:94

  @tf.function
  def serve_examples(self, inputs):
    features = tf.io.parse_example(inputs, self.name_to_features)
    for key in list(features.keys()):
      t = features[key]
      if t.dtype == tf.int64:
        t = tf.cast(t, tf.int32)
      features[key] = t
    return self.serve(
        features["input_ids"],
        input_mask=features["input_mask"] if "input_mask" in features else None,
        segment_ids=features["segment_ids"]
        if "segment_ids" in features else None)

  @classmethod
  def export(cls, model, export_dir):
    if not isinstance(model, cls):
      raise ValueError("Invalid model instance: %s, it should be a %s" %
                       (model, cls))

    signatures = {
        "serving_default":
            model.serve.get_concrete_function(
                input_ids=tf.TensorSpec(
                    shape=[None, None], dtype=tf.int32, name="inputs")),
    }
    if model.name_to_features:
      signatures[
          "serving_examples"] = model.serve_examples.get_concrete_function(
              tf.TensorSpec(shape=[None], dtype=tf.string, name="examples"))
    tf.saved_model.save(model, export_dir=export_dir, signatures=signatures)


def main(_):
  sequence_length = FLAGS.sequence_length
  if sequence_length is not None and sequence_length > 0:

View on GitHub (pinned to e006f5f0d5)

When it happens

Trigger: Thrown at official/legacy/bert/serving.py:94 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of tensorflow/models@e006f5f0d5 (2026-08-24). Data as JSON: /api/errors/2346d3493cc74fc6. Report an issue: GitHub.