#31 Made parallel task propagating exceptions (#72)

pytest-backend/doc/changes/changelog.md

@@ -5,6 +5,7 @@
 * [0.2.0](changes_0.2.0.md)
 * [0.2.1](changes_0.2.1.md)
 * [0.3.0](changes_0.3.0.md)
+* [0.3.1](changes_0.3.1.md)
 
 <!--- This MyST Parser Sphinx directive is necessary to keep Sphinx happy. We need list here all release letters again, because release droid and other scripts assume Markdown --->
 ```{toctree}
@@ -16,5 +17,6 @@ changes_0.1.0
 changes_0.2.0
 changes_0.2.1
 changes_0.3.0
+changes_0.3.1
 
 ```

pytest-backend/doc/changes/changes_0.3.1.md

@@ -0,0 +1,14 @@
+# 0.3.1 - 2024-10-31
+
+## Summary
+
+Relocked the dependencies and fixed the deficiencies of the 0.3.0
+
+## Documentation
+
+* #69: Fixed names of the CLI options in the user guide of pytest-exasol-backend
+
+## Refactorings
+
+* Relock dependencies
+* #71 Made the ParallelTask propagating exceptions to the caller.

pytest-backend/doc/changes/unreleased.md

@@ -1,9 +1 @@
 # Unreleased
-
-## Documentation
-
-* #69: Fixed names of CLI options in user guide of pytest-exasol-backend
-
-## Refactorings
-
-* Relock dependencies

pytest-backend/exasol/pytest_backend/parallel_task.py

@@ -17,12 +17,20 @@ def __init__(self, func, args, kwargs):
         self._proc: mp.Process | None = None
 
     def _run(self) -> None:
-        with self._ctx_func(*self._args, **self._kwargs) as output:
-            # Now the task has completed. Make the results available for
-            # caller and indicate the completion.
-            self._queue.put(output)
+        try:
+            with self._ctx_func(*self._args, **self._kwargs) as output:
+                # Now the task has completed. Make the results available for
+                # caller and indicate the completion.
+                # Return None as the error object followed by the function output.
+                self._queue.put(None)
+                self._queue.put(output)
+                self._ready.set()
+                # Wait until the caller is done and proceed with the cleanup.
+                self._done.wait()
+        except Exception as ex:
+            # Pass the exception back to the caller and wait until it's done.
+            self._queue.put(ex)
             self._ready.set()
-            # Wait until the caller is done and proceed with the cleanup.
             self._done.wait()
 
     def __enter__(self) -> "_ParallelGenCtxManager":
@@ -43,6 +51,11 @@ def wait(self, timeout: float | None = None) -> None:
             self._proc.kill()
             raise TimeoutError(f'{self._func_name} failed to complete within {timeout} seconds')
 
+        # Check if an exception is returned and if so re-raise it
+        error = self._queue.get()
+        if error is not None:
+            raise RuntimeError(f'{self._func_name} failed') from error
+
     def get_output(self, timeout: float | None = None) -> Any:
         self.wait(timeout)
         return self._queue.get()

pytest-backend/exasol/pytest_backend/version.py

@@ -6,5 +6,5 @@
 # If you need to change the version, do so in the project.toml, e.g. by using `poetry version X.Y.Z`.
 MAJOR = 0
 MINOR = 3
-PATCH = 0
+PATCH = 1
 VERSION = f"{MAJOR}.{MINOR}.{PATCH}"

pytest-backend/pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "pytest-exasol-backend"
-version = "0.3.0"
+version = "0.3.1"
 description = ""
 authors = ["Mikhail Beck <[email protected]>"]
 readme = "README.md"

pytest-backend/test/unit/test_parallel_task.py

@@ -2,6 +2,7 @@
 from contextlib import contextmanager
 from tempfile import NamedTemporaryFile
 import json
+import pytest
 
 from exasol.pytest_backend.parallel_task import paralleltask
 
@@ -32,3 +33,15 @@ def test_my_brewery():
         assert brewery_info['logos'] == ['Cambridge Beaver', 'Cam Droplets']
     # Now the flyer should be deleted
     assert not os.path.exists(flyer_file)
+
+
+@paralleltask
+def my_div(num: int, den: int):
+    yield num // den
+
+
+def test_div_by_zero():
+    with pytest.raises(RuntimeError) as ex_info:
+        with my_div(10, 0) as my_div_async:
+            my_div_async.get_output()
+    assert isinstance(ex_info.value.__cause__, ZeroDivisionError)