keras-team/keras

[Bug] deserialize_keras_object raises AttributeError for invalid config types

Closed

#22,701 opened on Apr 18, 2026

View on GitHubContributor guide
 (6 comments) (0 reactions) (1 assignee)Python (19,747 forks)batch import
Good first issuebackend:tensorflowstat:contributions welcometype:Bug

Repository metrics

Stars
 (64,219 stars)
PR merge metrics
 (Avg merge 6d 23h) (75 merged PRs in 30d)

Description

Description

deserialize_keras_object may raise AttributeError when provided with invalid config types (e.g., list or string), indicating that input validation occurs after internal method calls.

Reproduction Script

import os
os.environ["KERAS_BACKEND"] = "tensorflow"

from keras.saving import deserialize_keras_object

config = {
    "class_name": "Dense",
    "module": "keras.layers",
    "config": [1, 2, 3]   # invalid type
}

try:
    deserialize_keras_object(config)
except Exception as e:
    print("Exception type:", type(e).__name__)
    print("Message:", e)

Observed behavior

  • Raises AttributeError: 'list' object has no attribute 'get'

Expected behavior

  • Should raise a clear ValueError or TypeError for invalid input structure

Notes

This suggests input validation happens too late and exposes internal implementation details.

Contributor guide

Research direction
The bug is in the `deserialize keras object` function, likely in `keras/saving/`. The fix involves adding input validation at the start to ensure `config` is a dict and raising a clear `ValueError` or `TypeError` instead of an `AttributeError`. Examine the existing comments in the issue for any suggested approaches or additional context. The change is localized and should include a simple type check before calling `.get()` on the config.
Tech stack
python
Domain
backendmachine learning
Issue type
Bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Blocked
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
PythonError handling
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
30