Pydantic Pydantic FilePath does not accept sockets (Fix)

The Fix

pip install pydantic==2.9.2

Based on closed pydantic/pydantic issue #10376 · PR/commit linked

Production note: Most teams hit this during upgrades or environment changes. Roll out with a canary and smoke critical endpoints (health, OpenAPI/docs) before 100%.

Jump to Verify Open PR/Commit

@@ -177,6 +177,7 @@
     'SecretStr',
     'SecretBytes',
+    'SocketPath',
     'StrictBool',
     'StrictBytes',

repro.py

def test_pydantic_socket_validation():
    from pathlib import Path
    from pydantic import BaseModel, FilePath
    import socket


    class Reproduction(BaseModel):
        host: FilePath

    # clean up after ourselves
    socket_path = Path("/tmp")/"tmp_socket"
    socket_path.unlink(missing_ok=True)
    # create a socket
    sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
    sock.bind("/tmp/tmp_socket")

    # create the real files for comparison
    real_file = Path("/tmp") / "foo.txt"
    real_file.unlink(missing_ok=True)  # clean up after ourselves
    real_file.touch()
    link_to_real_file = Path("/tmp") / "foo.lnk.txt"
    link_to_real_file.unlink(missing_ok=True)  # clean up after ourselves
    link_to_real_file.symlink_to(real_file)
    # assert real path to real file works
    Reproduction(host="/tmp/foo.txt")
    # assert symlinked path to real file works
    Reproduction(host="/tmp/foo.lnk.txt")
    # assert real path to socket works
    Reproduction(host="/tmp/tmp_socket")  # explodes

verify

Re-run the minimal reproduction on your broken version, then apply the fix and re-run.

fix.md

Option A — Upgrade to fixed release\npip install pydantic==2.9.2\nWhen NOT to use: This fix is not applicable for non-Linux systems where socket validation is not supported.\n\n

Why This Fix Works in Production

Trigger: Reproduction(host="/tmp/tmp_socket") # explodes
Mechanism: Added a new `SocketPath` type to allow validation of Unix domain sockets in Pydantic, addressing issue #10376.
Why the fix works: Added a new `SocketPath` type to allow validation of Unix domain sockets in Pydantic, addressing issue #10376. (first fixed release: 2.9.2).

Production impact:

If left unfixed, the same config can fail only in production (env differences), causing startup failures or partial feature outages.

Why This Breaks in Prod

Shows up under Python 3.12 in real deployments (not just unit tests).
Surfaces as: Reproduction(host="/tmp/tmp_socket") # explodes

Proof / Evidence

GitHub issue: #10376
Fix PR: https://github.com/pydantic/pydantic/pull/10378
First fixed release: 2.9.2
Reproduced locally: No (not executed)
Last verified: 2026-02-09
Confidence: 0.85
Did this fix it?: Yes (upstream fix exists)
Own content ratio: 0.40

Discussion

High-signal excerpts from the issue thread (symptoms, repros, edge-cases).

Jump to Sources Open on GitHub

“### Initial Checks - [X] I confirm that I'm using Pydantic V2 ### Description I want to pass a file path to an existing unix domain socket to a pydantic class and have it validate that the path exists. from linux's perspective, its the same”

Issue thread · issue description · source

Failure Signature (Search String)

Reproduction(host="/tmp/tmp_socket") # explodes

Error Message

Stack trace

error.txt

Error Message
-------------
Reproduction(host="/tmp/tmp_socket")  # explodes
E       pydantic_core._pydantic_core.ValidationError: 1 validation error for Reproduction
E       host
E         Path does not point to a file [type=path_not_file, input_value='/tmp/tmp_socket', input_type=str]

Minimal Reproduction

repro.py

def test_pydantic_socket_validation():
    from pathlib import Path
    from pydantic import BaseModel, FilePath
    import socket


    class Reproduction(BaseModel):
        host: FilePath

    # clean up after ourselves
    socket_path = Path("/tmp")/"tmp_socket"
    socket_path.unlink(missing_ok=True)
    # create a socket
    sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
    sock.bind("/tmp/tmp_socket")

    # create the real files for comparison
    real_file = Path("/tmp") / "foo.txt"
    real_file.unlink(missing_ok=True)  # clean up after ourselves
    real_file.touch()
    link_to_real_file = Path("/tmp") / "foo.lnk.txt"
    link_to_real_file.unlink(missing_ok=True)  # clean up after ourselves
    link_to_real_file.symlink_to(real_file)
    # assert real path to real file works
    Reproduction(host="/tmp/foo.txt")
    # assert symlinked path to real file works
    Reproduction(host="/tmp/foo.lnk.txt")
    # assert real path to socket works
    Reproduction(host="/tmp/tmp_socket")  # explodes

Environment

Python: 3.12
Pydantic: 2

What Broke

Validation errors occur when attempting to validate Unix domain sockets as file paths.

Fix Options (Details)

Option A — Upgrade to fixed release Safe default (recommended)

pip install pydantic==2.9.2

When NOT to use: This fix is not applicable for non-Linux systems where socket validation is not supported.

Use when you can deploy the upstream fix. It is usually lower-risk than long-lived workarounds.

Fix reference: https://github.com/pydantic/pydantic/pull/10378

First fixed release: 2.9.2

Last verified: 2026-02-09. Validate in your environment.

When NOT to Use This Fix

This fix is not applicable for non-Linux systems where socket validation is not supported.

Verify Fix

verify

Re-run the minimal reproduction on your broken version, then apply the fix and re-run.

Did This Fix Work in Your Case?

Quick signal helps us prioritize which fixes to verify and improve.

Prevention

Add a CI check that diffs key outputs after upgrades (OpenAPI schema snapshots, JSON payload shapes, CLI output).
Upgrade behind a canary and run integration tests against the canary before 100% rollout.

Version Compatibility Table

Version	Status
2.9.2	Fixed

Related Issues

No related fixes found.

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Related clusters: Data consistency OpenAPI schema Serialization

Sources

We don’t republish the full GitHub discussion text. Use the links above for context.