Sync local paths in remote environments with the same OS.

.github/workflows/main.yml

@@ -18,20 +18,20 @@ on:
 
 jobs:
 
-  build-package:
-    name: Build & verify package
+  run-type-checking:
+
+    name: Run tests for type-checking
     runs-on: ubuntu-latest
 
     steps:
       - uses: actions/checkout@v4
+      - uses: actions/setup-python@v5
         with:
-          fetch-depth: 0
-
-      - uses: hynek/build-and-inspect-python-package@v2
-        id: baipp
-
-    outputs:
-      python-versions: ${{ steps.baipp.outputs.supported_python_classifiers_json_array }}
+          python-version-file: .python-version
+          allow-prereleases: true
+          cache: pip
+      - run: pip install tox-uv
+      - run: tox -e typing
 
   run-tests:
 
@@ -59,16 +59,16 @@ jobs:
         shell: bash -l {0}
         run: tox -e test -- tests -m "unit or (not integration and not end_to_end)" --cov=src --cov=tests --cov-report=xml
 
-      - name: Upload coverage report for unit tests and doctests.
-        if: runner.os == 'Linux' && matrix.python-version == '3.10'
-        shell: bash -l {0}
-        run: bash <(curl -s https://codecov.io/bash) -F unit -c
+      - name: Upload unit test coverage reports to Codecov with GitHub Action
+        uses: codecov/codecov-action@v4
+        with:
+          flags: unit
 
       - name: Run end-to-end tests.
         shell: bash -l {0}
         run: tox -e test -- tests -m end_to_end --cov=src --cov=tests --cov-report=xml
 
-      - name: Upload coverage reports of end-to-end tests.
-        if: runner.os == 'Linux' && matrix.python-version == '3.10'
-        shell: bash -l {0}
-        run: bash <(curl -s https://codecov.io/bash) -F end_to_end -c
+      - name: Upload end_to_end test coverage reports to Codecov with GitHub Action
+        uses: codecov/codecov-action@v4
+        with:
+          flags: end_to_end

.pre-commit-config.yaml

@@ -14,7 +14,7 @@ repos:
     -   id: no-commit-to-branch
         args: [--branch, main]
 -   repo: https://github.com/pre-commit/pygrep-hooks
-    rev: v1.10.0  # Use the ref you want to point at
+    rev: v1.10.0
     hooks:
     -   id: python-check-blanket-noqa
     -   id: python-check-mock-methods
@@ -44,39 +44,22 @@ repos:
             mdformat-black,
             mdformat-pyproject,
         ]
+        args: [--wrap, "88"]
         files: (docs/.)
-# Conflicts with admonitions.
-# -   repo: https://github.com/executablebooks/mdformat
-#     rev: 0.7.17
-#     hooks:
-#     -   id: mdformat
-#         additional_dependencies: [
-#             mdformat-gfm,
-#             mdformat-black,
-#         ]
-#         args: [--wrap, "88"]
+-   repo: https://github.com/executablebooks/mdformat
+    rev: 0.7.17
+    hooks:
+    -   id: mdformat
+        additional_dependencies: [
+            mdformat-gfm,
+            mdformat-black,
+        ]
+        args: [--wrap, "88"]
+        files: (README\.md)
 - repo: https://github.com/codespell-project/codespell
   rev: v2.2.6
   hooks:
     -   id: codespell
--   repo: https://github.com/pre-commit/mirrors-mypy
-    rev: 'v1.10.0'
-    hooks:
-    -   id: mypy
-        args: [
-            --no-strict-optional,
-            --ignore-missing-imports,
-        ]
-        additional_dependencies: [
-            attrs,
-            cloudpickle,
-            loky,
-            "git+https://github.com/pytask-dev/pytask.git@main",
-            rich,
-            types-click,
-            types-setuptools,
-        ]
-        pass_filenames: false
 -   repo: meta
     hooks:
     -   id: check-hooks-apply

docs/source/changes.md

@@ -23,6 +23,8 @@ releases are available on [PyPI](https://pypi.org/project/pytask-parallel) and
   interactions with adaptive scaling. {issue}`98` does handle the resulting issues: no
   strong adherence to priorities, no pending status.
 - {pull}`100` adds project management with rye.
+- {pull}`101` adds syncing for local paths as dependencies or products in remote
+  environments with the same OS.
 
 ## 0.4.1 - 2024-01-12
 

docs/source/coiled.md

@@ -66,6 +66,14 @@ configure the hardware and software environment.
 ```{literalinclude} ../../docs_src/coiled/coiled_functions_task.py
 ```
 
+By default, {func}`@coiled.function <coiled.function>`
+[scales adaptively](https://docs.coiled.io/user_guide/usage/functions/index.html#adaptive-scaling)
+to the workload. It means that coiled infers from the number of submitted tasks and
+previous runtimes, how many additional remote workers it should deploy to handle the
+workload. It provides a convenient mechanism to scale without intervention. Also,
+workers launched by {func}`@coiled.function <coiled.function>` will shutdown quicker
+than a cluster.
+
 ```{seealso}
 Serverless functions are more thoroughly explained in
 [coiled's guide](https://docs.coiled.io/user_guide/usage/functions/index.html).

docs/source/dask.md

@@ -83,15 +83,15 @@ You can find more information in the documentation for
 
 ## Remote
 
-You can learn how to deploy your tasks to a remote dask cluster in [this
-guide](https://docs.dask.org/en/stable/deploying.html). They recommend to use coiled for
-deployment to cloud providers.
+You can learn how to deploy your tasks to a remote dask cluster in
+[this guide](https://docs.dask.org/en/stable/deploying.html). They recommend to use
+coiled for deployment to cloud providers.
 
 [coiled](https://www.coiled.io/) is a product built on top of dask that eases the
 deployment of your workflow to many cloud providers like AWS, GCP, and Azure.
 
 If you want to run the tasks in your project on a cluster managed by coiled read
 {ref}`this guide <coiled-clusters>`.
 
-Otherwise, follow the instructions in [dask's
-guide](https://docs.dask.org/en/stable/deploying.html).
+Otherwise, follow the instructions in
+[dask's guide](https://docs.dask.org/en/stable/deploying.html).

docs/source/developers_guide.md

@@ -1,10 +1,9 @@
 # Developer's Guide
 
 `pytask-parallel` does not call the `pytask_execute_task_protocol` hook
-specification/entry-point because `pytask_execute_task_setup` and
-`pytask_execute_task` need to be separated from `pytask_execute_task_teardown`. Thus,
-plugins that change this hook specification may not interact well with the
-parallelization.
+specification/entry-point because `pytask_execute_task_setup` and `pytask_execute_task`
+need to be separated from `pytask_execute_task_teardown`. Thus, plugins that change this
+hook specification may not interact well with the parallelization.
 
 Two PRs for CPython try to re-enable setting custom reducers which should have been
 working but does not. Here are the references.

docs/source/index.md

@@ -26,6 +26,7 @@ quickstart
 coiled
 dask
 custom_executors
+remote_backends
 developers_guide
 changes
 On Github <https://github.com/pytask-dev/pytask-parallel>

docs/source/remote_backends.md

@@ -0,0 +1,47 @@
+# Remote backends
+
+There are a couple of things you need to know when using backends that launch workers
+remotely, meaning not on your machine.
+
+## Cross-platform support
+
+Issue: {issue}`102`.
+
+Currently, it is not possible to run tasks in a remote environment that has a different
+OS than your local system. The reason is that when pytask sends data to the remote
+worker, the data contains path objects, {class}`pathlib.WindowsPath` or
+{class}`pathlib.PosixPath`, which cannot be unpickled on a different system.
+
+In general, remote machines are Unix machines which means people running Unix systems
+themselves like Linux and MacOS should have no problems.
+
+Windows users on the other hand should use the
+[WSL (Windows Subsystem for Linux)](https://learn.microsoft.com/en-us/windows/wsl/about)
+to run their projects.
+
+## Local files
+
+Avoid using local files with remote backends and use storages like S3 for dependencies
+and products. The reason is that every local file needs to be send to the remote workers
+and when your internet connection is slow you will face a hefty penalty on runtime.
+
+## Local paths
+
+In most projects you are using local paths to refer to dependencies and products of your
+tasks. This becomes an interesting problem with remote workers since your local files
+are not necessarily available in the remote machine.
+
+pytask-parallel does its best to sync files before the execution to the worker, so you
+can run your tasks locally and remotely without changing a thing.
+
+In case you create a file on the remote machine, the product will be synced back to your
+local machine as well.
+
+It is still necessary to know that the remote paths are temporary files that share the
+same file extension as the local file, but the name and path will be different. Do not
+rely on them.
+
+Another way to circumvent the problem is to first define a local task that stores all
+your necessary files in a remote storage like S3. In the remaining tasks, you can then
+use paths pointing to the bucket instead of the local machine. See the
+[guide on remote files](https://tinyurl.com/pytask-remote) for more explanations.

pyproject.toml

@@ -55,21 +55,12 @@ content-type = "text/markdown"
 text = "MIT"
 
 [project.urls]
-Homepage = "https://github.com/pytask-dev/pytask-parallel"
-Changelog = "https://github.com/pytask-dev/pytask-parallel/blob/main/CHANGES.md"
-Documentation = "https://github.com/pytask-dev/pytask-parallel"
+Homepage = "https://pytask-parallel.readthedocs.io/"
+Changelog = "https://pytask-parallel.readthedocs.io/en/latest/changes.html"
+Documentation = "https://pytask-parallel.readthedocs.io/"
 Github = "https://github.com/pytask-dev/pytask-parallel"
 Tracker = "https://github.com/pytask-dev/pytask-parallel/issues"
 
-[tool.setuptools]
-include-package-data = true
-zip-safe = false
-platforms = ["any"]
-license-files = ["LICENSE"]
-
-[tool.check-manifest]
-ignore = ["src/pytask_parallel/_version.py"]
-
 [project.entry-points.pytask]
 pytask_parallel = "pytask_parallel.plugin"
 
@@ -113,6 +104,7 @@ disallow_untyped_defs = true
 no_implicit_optional = true
 warn_redundant_casts = true
 warn_unused_ignores = true
+ignore_missing_imports = true
 
 [[tool.mypy.overrides]]
 module = "tests.*"
@@ -127,6 +119,7 @@ unsafe-fixes = true
 [tool.ruff.lint]
 extend-ignore = [
     "ANN101",  # type annotating self
+    "ANN102",  # type annotating cls
     "ANN401",  # flake8-annotate typing.Any
     "COM812",  # Comply with ruff-format.
     "ISC001",  # Comply with ruff-format.

src/pytask_parallel/backends.py

@@ -46,10 +46,11 @@ def submit(  # type: ignore[override]
 
 def _get_dask_executor(n_workers: int) -> Executor:
     """Get an executor from a dask client."""
-    _rich_traceback_omit = True
+    _rich_traceback_guard = True
     from pytask import import_optional_dependency
 
     distributed = import_optional_dependency("distributed")
+    assert distributed  # noqa: S101
     try:
         client = distributed.Client.current()
     except ValueError:

src/pytask_parallel/config.py

@@ -27,7 +27,7 @@ def pytask_parse_config(config: dict[str, Any]) -> None:
         raise ValueError(msg) from None
 
     if config["n_workers"] == "auto":
-        config["n_workers"] = max(os.cpu_count() - 1, 1)
+        config["n_workers"] = max(os.cpu_count() - 1, 1)  # type: ignore[operator]
 
     # If more than one worker is used, and no backend is set, use loky.
     if config["n_workers"] > 1 and config["parallel_backend"] == ParallelBackend.NONE:

src/pytask_parallel/execute.py

@@ -8,6 +8,7 @@
 from typing import Any
 
 import cloudpickle
+from _pytask.node_protocols import PPathNode
 from attrs import define
 from attrs import field
 from pytask import ExecutionReport
@@ -24,9 +25,10 @@
 
 from pytask_parallel.backends import WorkerType
 from pytask_parallel.backends import registry
+from pytask_parallel.typing import CarryOverPath
+from pytask_parallel.typing import is_coiled_function
 from pytask_parallel.utils import create_kwargs_for_task
 from pytask_parallel.utils import get_module
-from pytask_parallel.utils import is_coiled_function
 from pytask_parallel.utils import parse_future_result
 
 if TYPE_CHECKING:
@@ -222,7 +224,7 @@ def pytask_execute_task(session: Session, task: PTask) -> Future[WrapperResult]:
         from pytask_parallel.wrappers import wrap_task_in_thread
 
         return session.config["_parallel_executor"].submit(
-            wrap_task_in_thread, task=task, **kwargs
+            wrap_task_in_thread, task=task, remote=False, **kwargs
         )
     msg = f"Unknown worker type {worker_type}"
     raise ValueError(msg)
@@ -235,19 +237,33 @@ def pytask_unconfigure() -> None:
 
 
 def _update_carry_over_products(
-    task: PTask, carry_over_products: PyTree[PythonNode | None] | None
+    task: PTask, carry_over_products: PyTree[CarryOverPath | PythonNode | None] | None
 ) -> None:
-    """Update products carry over from a another process or remote worker."""
+    """Update products carry over from a another process or remote worker.
 
-    def _update_carry_over_node(x: PNode, y: PythonNode | None) -> PNode:
-        if y:
+    The python node can be a regular one passing the value to another python node.
+
+    In other instances the python holds a string or bytes from a RemotePathNode.
+
+    """
+
+    def _update_carry_over_node(
+        x: PNode, y: CarryOverPath | PythonNode | None
+    ) -> PNode:
+        if y is None:
+            return x
+        if isinstance(x, PPathNode) and isinstance(y, CarryOverPath):
+            x.path.write_bytes(y.content)
+            return x
+        if isinstance(y, PythonNode):
             x.save(y.load())
-        return x
+            return x
+        raise NotImplementedError
 
-    structure_python_nodes = tree_structure(carry_over_products)
+    structure_carry_over_products = tree_structure(carry_over_products)
     structure_produces = tree_structure(task.produces)
     # strict must be false when none is leaf.
-    if structure_produces.is_prefix(structure_python_nodes, strict=False):
+    if structure_produces.is_prefix(structure_carry_over_products, strict=False):
         task.produces = tree_map(
             _update_carry_over_node, task.produces, carry_over_products
         )  # type: ignore[assignment]