feat: use variable name as download filename in dataframe viewer by AhmadYasser1 · Pull Request #8227 · marimo-team/marimo

AhmadYasser1 · 2026-02-08T20:04:34Z

Summary

Downloaded files from the dataframe viewer used a generic download.csv name. Now threads the variable name from the plugin through to the download action so the file is named after the variable (e.g. my_dataframe.csv).

Closes #8095

Test Plan

Added test for download filename propagation

The rich dataframe viewer now names download files after the variable (e.g., "my_df.csv" instead of "download.csv"). The backend already extracts and sends the variable name; this change threads it through the frontend components to the download action. Closes marimo-team#8095

for more information, see https://pre-commit.ci

vercel · 2026-02-08T20:04:39Z

The latest updates on your projects. Learn more about Vercel for GitHub.

Project	Deployment	Actions	Updated (UTC)
marimo-docs	Ready	Preview, Comment	Feb 10, 2026 4:18pm

- Add downloadFileName to the withData Zod schema so it isn't stripped during parsing - Sanitize the filename: trim whitespace, strip existing extension to prevent double extensions, fall back to "download" if empty

for more information, see https://pre-commit.ci

Light2Dark

The donwloadFileName is not passed from the backend. Is that a follow-up?

Infer the variable name via inspect.currentframe() (same pattern as DataFramePlugin) and pass it as download-file-name in component args so the frontend can use it for the download filename.

AhmadYasser1 · 2026-02-09T12:58:22Z

Good catch — I've now added the backend side. The table's __init__ infers the variable name via inspect.currentframe() (same pattern as DataFramePlugin) and passes it as download-file-name in the component args. Also added a test for it.

Copilot

Pull request overview

Threads a dataframe/table variable name through the plugin/data-table stack so that downloads from the rich dataframe viewer (and tables) use a meaningful filename instead of a generic download.*.

Changes:

Added dataframeName support to the dataframe viewer plugin and passed it into the shared data-table download action.
Added downloadFileName support to the table plugin and propagated it through the data-table components.
Updated download action to derive ${baseName}.${ext} and added a Python unit test for table filename propagation.

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
tests/_plugins/ui/_impl/test_table.py	Adds a unit test asserting `ui.table()` sets the download filename argument.
marimo/_plugins/ui/_impl/table.py	Infers a download filename via frame locals and emits it as a component arg.
frontend/src/plugins/impl/data-frames/DataFramePlugin.tsx	Accepts `dataframeName` and passes it to the shared data-table as `downloadFileName`.
frontend/src/plugins/impl/DataTablePlugin.tsx	Adds `downloadFileName` to plugin schema/props and passes it into the table component tree.
frontend/src/components/data-table/download-actions.tsx	Uses `downloadFileName` to name downloaded files instead of `download.*`.
frontend/src/components/data-table/data-table.tsx	Plumbs `downloadFileName` into `TableActions`.
frontend/src/components/data-table/TableActions.tsx	Passes `downloadFileName` into `DownloadAs`.

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

Copilot · 2026-02-09T20:26:30Z

marimo/_plugins/ui/_impl/table.py

+            if frame is not None and frame.f_back is not None:
+                for var_name, var_value in frame.f_back.f_locals.items():
+                    if var_value is data:
+                        download_file_name = var_name


The variable-name inference compares locals against data after add_selection_column() may have converted/replaced the original input (notably for dataframe inputs). For ui.table(df) this will likely fail to match the caller’s df variable (identity check won’t match the new object), so downloads will still fall back to "download". Consider capturing the original argument before mutation (or compute the name before add_selection_column()), and use that for the identity match / filename propagation.

Copilot · 2026-02-09T20:26:31Z

marimo/_plugins/ui/_impl/table.py

+        try:
+            frame = inspect.currentframe()
+            if frame is not None and frame.f_back is not None:
+                for var_name, var_value in frame.f_back.f_locals.items():
+                    if var_value is data:
+                        download_file_name = var_name
+                        break
+        except Exception:
+            pass


inspect.currentframe() can create reference cycles; without explicitly clearing the frame reference, this can delay GC in long-running sessions. Consider using a finally block to del frame (and any other frame refs) after the lookup to avoid leaking frames.

Suggested change

try:

frame = inspect.currentframe()

if frame is not None and frame.f_back is not None:

for var_name, var_value in frame.f_back.f_locals.items():

if var_value is data:

download_file_name = var_name

break

except Exception:

pass

frame = None

frame_back = None

try:

frame = inspect.currentframe()

if frame is not None:

frame_back = frame.f_back

if frame_back is not None:

for var_name, var_value in frame_back.f_locals.items():

if var_value is data:

download_file_name = var_name

break

except Exception:

pass

finally:

del frame

del frame_back

Copilot · 2026-02-09T20:26:31Z

frontend/src/components/data-table/download-actions.tsx

+              const rawName = (props.downloadFileName ?? "").trim();
+              const baseName = rawName.replace(/\.[^/.]+$/, "") || "download";
+              downloadByURL(downloadUrl, `${baseName}.${ext}`);


This duplicates filename-extension stripping logic that already exists in frontend/src/utils/filenames.ts (withoutExtension/replace). Using the shared utility here would reduce duplication and keep filename rules consistent across download entry points.

Copilot · 2026-02-09T20:26:31Z

frontend/src/components/data-table/download-actions.tsx

            onSelect={async () => {
              const downloadUrl = await getDownloadUrl(option.format);
              const ext = option.format;
-              downloadByURL(downloadUrl, `download.${ext}`);
+              const rawName = (props.downloadFileName ?? "").trim();
+              const baseName = rawName.replace(/\.[^/.]+$/, "") || "download";
+              downloadByURL(downloadUrl, `${baseName}.${ext}`);


The new filename propagation logic isn’t covered by a frontend test. Since the repo already has Vitest coverage for the data-table plugin, consider adding a unit test that asserts DownloadAs calls downloadByURL with the expected ${baseName}.${ext} when downloadFileName is provided (and falls back to download.* when it isn’t).

Copilot · 2026-02-09T20:26:32Z

marimo/_plugins/ui/_impl/table.py

+                        download_file_name = var_name
+                        break
+        except Exception:
+            pass


'except' clause does nothing but pass and there is no explanatory comment.

Suggested change

pass

LOGGER.debug(

"Failed to infer download file name from caller frame.",

exc_info=True,

)

- move variable name inference before add_selection_column() so the identity check still matches the caller's original variable - clean up inspect.currentframe() refs in a finally block to avoid reference cycles in long-running sessions - log the exception instead of bare pass - use shared Filenames.withoutExtension() instead of inline regex

AhmadYasser1 · 2026-02-10T02:31:00Z

pushed fixes for the review feedback:

moved the variable name inference before add_selection_column() so the identity check works correctly on the original data
added finally: del frame / del frame_back to avoid reference cycles
swapped the inline regex for the shared Filenames.withoutExtension() utility
added LOGGER.debug(...) instead of bare pass

Light2Dark

.

Light2Dark · 2026-02-10T11:08:33Z

marimo/_plugins/ui/_impl/table.py

+        download_file_name = "download"
+        frame = None
+        frame_back = None
+        try:
+            frame = inspect.currentframe()
+            if frame is not None:
+                frame_back = frame.f_back
+            if frame_back is not None:
+                for var_name, var_value in frame_back.f_locals.items():
+                    if var_value is data:
+                        download_file_name = var_name
+                        break
+        except Exception:
+            LOGGER.debug(
+                "Failed to infer download file name from caller frame.",
+                exc_info=True,
+            )
+        finally:
+            del frame
+            del frame_back


i would maybe refator this to a utility function, since dataframe.py uses it too

good call, extracted it into marimo/_utils/variable_name.py — both table.py and dataframe.py now use infer_variable_name(value, fallback) instead of duplicating the frame-walking logic.

Move the `inspect.currentframe()` variable-name lookup used by both `table.py` and `dataframe.py` into `marimo/_utils/variable_name.py`. Both callers now use `infer_variable_name(value, fallback)` instead of duplicating the frame-walking logic.

Light2Dark

lgtm, just a small change for correctness

Light2Dark · 2026-02-10T15:37:05Z

marimo/_utils/variable_name.py

+from typing import Any
+
+LOGGER = logging.getLogger(__name__)


I don't know why I can't suggest code anymore, sigh GitHub UI

from marimo import _loggers LOGGER = _loggers.marimo_logger()

Removed unused logging import.

github-actions · 2026-02-10T16:38:23Z

🚀 Development release published. You may be able to view the changes at https://marimo.app?v=0.19.10-dev38

AhmadYasser1 · 2026-02-10T21:40:41Z

Thanks @mscolnick and @Light2Dark ! Appreciate the help and feedback :)

AhmadYasser1 and others added 2 commits February 8, 2026 03:20

[pre-commit.ci] auto fixes from pre-commit.com hooks

298838a

for more information, see https://pre-commit.ci

AhmadYasser1 requested review from Light2Dark and manzt as code owners February 8, 2026 20:04

fix: add downloadFileName to Zod schema and sanitize filename

202a1cb

- Add downloadFileName to the withData Zod schema so it isn't stripped during parsing - Sanitize the filename: trim whitespace, strip existing extension to prevent double extensions, fall back to "download" if empty

vercel bot deployed to Preview February 8, 2026 20:09 View deployment

[pre-commit.ci] auto fixes from pre-commit.com hooks

48206ac

for more information, see https://pre-commit.ci

vercel bot deployed to Preview February 8, 2026 20:27 View deployment

Light2Dark requested changes Feb 9, 2026

View reviewed changes

fix: pass download filename from Python backend to frontend

7df5933

Infer the variable name via inspect.currentframe() (same pattern as DataFramePlugin) and pass it as download-file-name in component args so the frontend can use it for the download filename.

vercel bot deployed to Preview February 9, 2026 12:59 View deployment

mscolnick requested a review from Copilot February 9, 2026 20:20

Copilot started reviewing on behalf of mscolnick February 9, 2026 20:21 View session

Copilot AI reviewed Feb 9, 2026

View reviewed changes

vercel bot deployed to Preview February 10, 2026 02:31 View deployment

mscolnick added the bug Something isn't working label Feb 10, 2026

Light2Dark reviewed Feb 10, 2026

View reviewed changes

vercel bot deployed to Preview February 10, 2026 12:40 View deployment

Light2Dark reviewed Feb 10, 2026

View reviewed changes

Update variable_name.py

57e4eed

vercel bot deployed to Preview February 10, 2026 15:49 View deployment

Remove unused import of logging module

bdc5119

Removed unused logging import.

vercel bot deployed to Preview February 10, 2026 16:18 View deployment

Light2Dark approved these changes Feb 10, 2026

View reviewed changes

mscolnick merged commit af37b9b into marimo-team:main Feb 10, 2026
25 of 39 checks passed

AhmadYasser1 deleted the feat/download-filename-variable branch February 10, 2026 16:35

Conversation

AhmadYasser1 commented Feb 8, 2026

Summary

Test Plan

Uh oh!

vercel bot commented Feb 8, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

Light2Dark left a comment • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Choose a reason for hiding this comment

Uh oh!

AhmadYasser1 commented Feb 9, 2026

Uh oh!

Copilot AI left a comment

Choose a reason for hiding this comment

Pull request overview

Reviewed changes

Uh oh!

Copilot AI Feb 9, 2026

Choose a reason for hiding this comment

Uh oh!

Copilot AI Feb 9, 2026

Choose a reason for hiding this comment

Uh oh!

Copilot AI Feb 9, 2026

Choose a reason for hiding this comment

Uh oh!

Copilot AI Feb 9, 2026

Choose a reason for hiding this comment

Uh oh!

Copilot AI Feb 9, 2026

Choose a reason for hiding this comment

Uh oh!

AhmadYasser1 commented Feb 10, 2026

Uh oh!

Light2Dark left a comment • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Light2Dark Feb 10, 2026

Choose a reason for hiding this comment

Uh oh!

AhmadYasser1 Feb 10, 2026

Choose a reason for hiding this comment

Uh oh!

Light2Dark left a comment

Choose a reason for hiding this comment

Uh oh!

Light2Dark Feb 10, 2026

Choose a reason for hiding this comment

Uh oh!

Uh oh!

github-actions bot commented Feb 10, 2026

Uh oh!

AhmadYasser1 commented Feb 10, 2026

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

4 participants

vercel bot commented Feb 8, 2026 •

edited

Loading

Light2Dark left a comment •

edited

Loading

Light2Dark left a comment •

edited

Loading