c4cb7607ee
Applies the fix from PR #9422 (commit 18e2ff2d2d) to the lfx module,
which was previously only applied to the backend module.
PR #9422 fixed a bug where environment variable fallback would fail when
`load_from_db=True` inputs couldn't find variables in the database.
The fix properly distinguishes between two error cases:
- "User id is not set" → always raise (authentication issue)
- "variable not found." → only raise if fallback_to_env_vars=False
However, this fix was only applied to:
- src/backend/base/langflow/interface/initialize/loading.py
And was missing from:
- src/lfx/src/lfx/interface/initialize/loading.py
PR #9902 added table field support and reorganized the test imports to
use the lfx module (which has table support). The test was updated to
use "Database connection failed" error message to work with the existing
code, rather than "variable not found." which would trigger the bug.
This commit:
1. Applies the bug fix to the lfx module's regular field handler
2. Restores the original test behavior using "variable not found."
to properly validate that the fix works
- src/lfx/src/lfx/interface/initialize/loading.py
Fixed error handling to respect fallback_to_env_vars flag
- src/backend/tests/unit/interface/initialize/test_loading.py
Restored "variable not found." error to properly validate the fix
Fixes: https://github.com/langflow-ai/langflow/issues/11422
Related: #9422, #9902
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.
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