v1.14.2: /datasets/indexing-estimate 400 - enable: null in summary_index_setting causes validation error

[P1K3S]

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Dify version

v1.14.2

Cloud or Self Hosted

Self Hosted (Docker)

Steps to reproduce

1. Create a new dataset and save it.
2. Enter the existing dataset and try to upload a file (such as TXT/MD).
3. The frontend automatically calls /console/api/datasets/indexing-estimate.
4. The interface returns 400 Bad Request and cannot continue.

✔️ Expected Behavior

The file upload and indexing estimation functions should work normally in both new datasets and existing datasets. The frontend should not pass invalid null values to the backend.

❌ Actual Behavior

Actual Behavior

When uploading files in an existing dataset, the frontend automatically adds the field summary_index_setting: {"enable": null} to the request body. The backend performs strict Boolean verification, so null is regarded as an invalid parameter, resulting in a 400 error.

Normal request (New dataset, no error)

{
    "info_list":{"data_source_type":"upload_file","file_info_list":{"file_ids":["3e8681d8-7188-4794-94b7-47eb65bcaefc"]}},
    "indexing_technique":"high_quality",
    "process_rule":{"rules":{"pre_processing_rules":[{"id":"remove_extra_spaces","enabled":true},{"id":"remove_urls_emails","enabled":false}],"segmentation":{"separator":"\n\n","max_tokens":1024,"chunk_overlap":50}},
    "mode":"custom",
    "doc_form":"text_model",
    "doc_language":"Chinese Simplified"
}

Faulty request (Existing dataset, throw error)

{
    "info_list":{"data_source_type":"upload_file","file_info_list":{"file_ids":["4e4b85e3-4c36-4f4d-a7d7-27d4a94759d0"]}},
    "indexing_technique":"high_quality",
    "process_rule":{"rules":{"pre_processing_rules":[{"id":"remove_extra_spaces","enabled":true},{"id":"remove_urls_emails","enabled":false}],"segmentation":{"separator":"\n\n","max_tokens":1024,"chunk_overlap":50}},
    "mode":"custom",
    "summary_index_setting":{"enable":null,"model_name":null,"model_provider_name":null,"summary_prompt":null},
    "doc_form":"text_model",
    "doc_language":"Chinese Simplified",
    "dataset_id":"56feabbb-d845-431c-9833-6cbf276cf9a9"
}

[dosubot]

Hi @P1K3S! I'm Dosu and I’m helping the dify team.

This is a confirmed bug that was introduced by the Pydantic v2 validation refactor in PR #36036 (merged May 12, 2026). The strict Literal[True] | Literal[False] discriminated union for summary_index_setting.enable rejects null values, and the frontend passes through {"enable": null, ...} for existing datasets [1].

There are open PRs targeting this fix:

• PR #36355 — adds a field_validator with mode="before" to normalize dicts with enable=None to None [2]
• PR #36251 — similar fix for null handling [3]

Workaround until a fix is released: If you can intercept or modify the request (e.g., via a browser extension or API proxy), either:

1. Remove summary_index_setting from the request body entirely
2. Set summary_index_setting to null (instead of an object with null fields)
3. Set it to {"enable": false, "model_name": "", "model_provider_name": "", "summary_prompt": ""}

This same issue was reported in #36233 for the Knowledge Pipeline context [4].

To reply, just mention @dosu.

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[P1K3S]

When creating a new knowledge base, if the automatic summary generation option is never toggled and remains untouched, its value stays null. Later adding content to this dataset will trigger validation error.

The fix is to enter dataset settings, switch the automatic summary generation toggle on and off once, then save. This locks the parameter into valid boolean state and resolves the error.