From d8bb6d091b17f3c4d4f54e15d1eaacee064c8ab2 Mon Sep 17 00:00:00 2001
From: Pascal Tomecek <40371786+ptomecek@users.noreply.github.com>
Date: Tue, 27 Oct 2026 18:54:06 -0400
Subject: [PATCH] [bug] Import yaml lazily in the YAML publishers

pyyaml was only installed transitively through hydra-core, which is now
optional, so a bare install could not import ccflow. Import it inside
YAMLPublisher and PrintYAMLPublisher instead of at module level.

Signed-off-by: Pascal Tomecek <40371786+ptomecek@users.noreply.github.com>
---
 ccflow/publishers/file.py  | 3 ++-
 ccflow/publishers/print.py | 3 ++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/ccflow/publishers/file.py b/ccflow/publishers/file.py
index a0ba489b..58083ee5 100644
--- a/ccflow/publishers/file.py
+++ b/ccflow/publishers/file.py
@@ -4,7 +4,6 @@
 
 import narwhals.stable.v1 as nw
 import pandas as pd
-import yaml
 from cloudpathlib import AnyPath
 from pydantic import Field, field_validator
 from typing_extensions import override
@@ -91,6 +90,8 @@ class YAMLPublisher(BasePublisher):
 
     @override
     def __call__(self) -> AnyPath:
+        import yaml
+
         return GenericFilePublisher(
             name=self.name,
             name_params=self.name_params,
diff --git a/ccflow/publishers/print.py b/ccflow/publishers/print.py
index 8b08c957..1eff49ef 100644
--- a/ccflow/publishers/print.py
+++ b/ccflow/publishers/print.py
@@ -1,7 +1,6 @@
 import logging
 from typing import Any, Generic, Literal
 
-import yaml
 from pydantic import Field, field_validator
 from typing_extensions import override
 
@@ -77,6 +76,8 @@ class PrintYAMLPublisher(BasePublisher):
 
     @override
     def __call__(self) -> Any:
+        import yaml
+
         print(yaml.dump(self.data, **self.kwargs))
         return self.data