Merge pull request #337 from opensafely-core/remove-pydantic

Remove pydantic dependency

README.md

@@ -8,7 +8,7 @@ For example:
         data = load_pipeline(f.read())
 
 
-The returned object is a Pydantic model, `Pipeline`, defined in `pipeline/models.py`.
+The returned object is an instance of `pipeline.models.Pipeline`.
 
 
 ## Developer docs

pipeline/exceptions.py

@@ -8,3 +8,7 @@ class InvalidPatternError(ProjectValidationError):
 
 class YAMLError(Exception):
     pass
+
+
+class ValidationError(Exception):
+    pass

pipeline/legacy.py

@@ -5,8 +5,8 @@
 
 def get_all_output_patterns_from_project_file(project_file: str) -> list[str]:
     config = load_pipeline(project_file)
-    all_patterns = set()
+    all_patterns: set[str] = set()
     for action in config.actions.values():
-        for patterns in action.outputs.dict(exclude_unset=True).values():
+        for patterns in action.outputs.dict().values():
             all_patterns.update(patterns.values())
     return list(all_patterns)

pipeline/main.py

@@ -2,9 +2,7 @@
 
 from pathlib import Path
 
-import pydantic
-
-from .exceptions import ProjectValidationError, YAMLError
+from .exceptions import ProjectValidationError, ValidationError, YAMLError
 from .loading import parse_yaml_file
 from .models import Pipeline
 
@@ -27,8 +25,8 @@ def load_pipeline(pipeline_config: str | Path, filename: str | None = None) -> P
 
     # validate
     try:
-        return Pipeline(**parsed_data)
-    except pydantic.ValidationError as exc:
+        return Pipeline.build(**parsed_data)
+    except ValidationError as exc:
         raise ProjectValidationError(
             f"Invalid project: {filename or ''}\n{exc}"
         ) from exc