Viktor Avelino b288b3971f fix: support ZIP file upload for flows and projects endpoints (#12253)
* feat: support ZIP file upload for flows and projects endpoints

Add ZIP upload support to both /flows/upload/ and /projects/upload/
endpoints, enabling round-trip download-then-upload workflows. Extract
shared ZIP parsing logic into a dedicated utility with zip bomb
protections (entry count and file size limits). Fix batch flow name
deduplication to avoid infinite loops and DB collisions. Add tests for
ZIP upload, empty ZIP rejection, and download-upload round-trip.

* fix: add type annotation to satisfy mypy union narrowing

* fix: address PR review for ZIP upload (#12253)

- Add BadZipFile handling in extract_flows_from_zip for defense-in-depth
- Wrap blocking ZIP I/O in asyncio.to_thread() to avoid event loop blocking
- Add post-read size check to guard against dishonest ZIP headers
- Add 7 adversarial tests: invalid JSON, max entries, oversized entries,
  mixed valid/invalid, filename fallback, corrupt ZIP, batch name dedup

* fix: return 400 instead of 500 for missing, empty, or invalid file uploads

Upload endpoints were returning 500 when no file was provided or when the
file contained empty/invalid content. Now properly validates and returns
400 with descriptive messages for: no file provided, empty file, and
invalid JSON content.
2026-03-23 18:09:26 +00:00
2025-03-20 00:05:55 +00:00
2026-03-16 10:42:08 +00:00
2025-11-24 02:02:01 +00:00
2025-12-19 16:48:08 +00:00

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Langflow is a powerful platform for building and deploying AI-powered agents and workflows. It provides developers with both a visual authoring experience and built-in API and MCP servers that turn every workflow into a tool that can be integrated into applications built on any framework or stack. Langflow comes with batteries included and supports all major LLMs, vector databases and a growing library of AI tools.

Highlight features

  • Visual builder interface to quickly get started and iterate.
  • Source code access lets you customize any component using Python.
  • Interactive playground to immediately test and refine your flows with step-by-step control.
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Requires Python 3.103.13 and uv (recommended package manager).

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From a fresh directory, run:

uv pip install langflow -U

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If you've cloned this repository and want to contribute, run this command from the repository root:

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Start a Langflow container with default settings:

docker run -p 7860:7860 langflowai/langflow:latest

Langflow is available at http://localhost:7860/. For configuration options, see the Docker deployment guide.

Caution

  • Users must update to Langflow >= 1.7.1 to protect against CVE-2025-68477 and CVE-2025-68478.
  • Langflow version 1.7.0 has a critical bug where persisted state (flows, projects, and global variables) cannot be found when upgrading. Version 1.7.0 was yanked and replaced with version 1.7.1, which includes a fix for this bug. DO NOT upgrade to version 1.7.0. Instead, upgrade directly to version 1.7.1.
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  • Users must update to Langflow >= 1.5.1 to protect against CVE-2025-57760

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