Replace pony with sqlalchemy>=1.4.36.

docs/rtd_environment.yml

@@ -25,10 +25,10 @@ dependencies:
   - click-default-group
   - networkx >=2.4
   - pluggy
-  - pony >=0.7.15
   - pybaum >=0.1.1
   - pexpect
   - rich
+  - sqlalchemy >=1.4.36
   - tomli >=1.0.0
 
   - pip:

docs/source/changes.md

@@ -8,6 +8,7 @@ releases are available on [PyPI](https://pypi.org/project/pytask) and
 ## 0.4.0 - 2023-xx-xx
 
 - {pull}`323` remove Python 3.7 support and use a new Github action to provide mamba.
+- {pull}`387` replaces pony with sqlalchemy.
 
 ## 0.3.2 - 2023-06-07
 

docs/source/reference_guides/configuration.md

@@ -42,6 +42,23 @@ are welcome to also support macOS.
 
 ````
 
+````{confval} database_url
+
+pytask uses a database to keep track of tasks, products, and dependencies over runs. By
+default, it will create an SQLITE database in the project's root directory called
+`.pytask.sqlite3`. If you want to use a different name or a different dialect
+[supported by sqlalchemy](https://docs.sqlalchemy.org/en/latest/core/engines.html#backend-specific-urls),
+use either {option}`pytask build --database-url` or `database_url` in the config.
+
+```toml
+database_url = "sqlite:///.pytask.sqlite3"
+```
+
+Relative paths for SQLITE databases are interpreted as either relative to the
+configuration file or the root directory.
+
+````
+
 ````{confval} editor_url_scheme
 
 Depending on your terminal, pytask is able to turn task ids into clickable links to the

environment.yml

@@ -16,9 +16,9 @@ dependencies:
   - click-default-group
   - networkx >=2.4
   - pluggy
-  - pony >=0.7.15
   - pybaum >=0.1.1
   - rich
+  - sqlalchemy >=1.4.36
   - tomli >=1.0.0
 
   # Misc

setup.cfg

@@ -36,9 +36,9 @@ install_requires =
     networkx>=2.4
     packaging
     pluggy
-    pony>=0.7.15
     pybaum>=0.1.1
     rich
+    sqlalchemy>=1.4.36
     tomli>=1.0.0
 python_requires = >=3.8
 include_package_data = True

src/_pytask/clean.py

@@ -195,7 +195,10 @@ def _collect_all_paths_known_to_pytask(session: Session) -> set[Path]:
     if session.config["config"]:
         known_paths.add(session.config["config"])
     known_paths.add(session.config["root"])
-    known_paths.add(session.config["database_filename"])
+
+    database_url = session.config["database_url"]
+    if database_url.drivername == "sqlite" and database_url.database:
+        known_paths.add(Path(database_url.database))
 
     # Add files tracked by git.
     if is_git_installed():

src/_pytask/click.py

@@ -242,11 +242,11 @@ def _format_help_text(  # noqa: C901, PLR0912, PLR0915
 
     if show_default_is_str or (show_default and (default_value is not None)):
         if show_default_is_str:
-            default_string = f"({param.show_default})"  # type: ignore[attr-defined]
+            default_string = param.show_default  # type: ignore[attr-defined]
         elif isinstance(default_value, (list, tuple)):
             default_string = ", ".join(str(d) for d in default_value)
         elif inspect.isfunction(default_value):
-            default_string = _("(dynamic)")
+            default_string = _("dynamic")
         elif param.is_bool_flag and param.secondary_opts:  # type: ignore[attr-defined]
             # For boolean flags that have distinct True/False opts,
             # use the opt without prefix instead of the value.

src/_pytask/dag.py

@@ -16,6 +16,7 @@
 from _pytask.dag_utils import node_and_neighbors
 from _pytask.dag_utils import task_and_descending_tasks
 from _pytask.dag_utils import TopologicalSorter
+from _pytask.database_utils import DatabaseSession
 from _pytask.database_utils import State
 from _pytask.exceptions import ResolvingDependenciesError
 from _pytask.mark import Mark
@@ -30,7 +31,6 @@
 from _pytask.shared import reduce_names_of_multiple_nodes
 from _pytask.shared import reduce_node_name
 from _pytask.traceback import render_exc_info
-from pony import orm
 from pybaum import tree_map
 from rich.text import Text
 from rich.tree import Tree
@@ -126,7 +126,6 @@ def _have_task_or_neighbors_changed(
     )
 
 
-@orm.db_session
 @hookimpl(trylast=True)
 def pytask_dag_has_node_changed(node: MetaNode, task_name: str) -> bool:
     """Indicate whether a single dependency or product has changed."""
@@ -136,11 +135,11 @@ def pytask_dag_has_node_changed(node: MetaNode, task_name: str) -> bool:
         if file_state is None:
             return True
 
+        with DatabaseSession() as session:
+            db_state = session.get(State, (task_name, node.name))
+
         # If the node is not in the database.
-        try:
-            name = node.name
-            db_state = State[task_name, name]  # type: ignore[type-arg, valid-type]
-        except orm.ObjectNotFound:
+        if db_state is None:
             return True
 
         # If the modification times match, the node has not been changed.

src/_pytask/database.py

@@ -1,86 +1,43 @@
-"""Implement the database managed with pony."""
+"""Contains hooks related to the database."""
 from __future__ import annotations
 
-import enum
 from pathlib import Path
 from typing import Any
 
-import click
-from _pytask.click import EnumChoice
 from _pytask.config import hookimpl
 from _pytask.database_utils import create_database
-from click import Context
-
-
-class _DatabaseProviders(enum.Enum):
-    SQLITE = "sqlite"
-    POSTGRES = "postgres"
-    MYSQL = "mysql"
-    ORACLE = "oracle"
-    COCKROACH = "cockroach"
-
-
-def _database_filename_callback(
-    ctx: Context, name: str, value: str | None  # noqa: ARG001
-) -> str | None:
-    if value is None:
-        return ctx.params["root"].joinpath(".pytask.sqlite3")
-    return value
-
-
-@hookimpl
-def pytask_extend_command_line_interface(cli: click.Group) -> None:
-    """Extend command line interface."""
-    additional_parameters = [
-        click.Option(
-            ["--database-provider"],
-            type=EnumChoice(_DatabaseProviders),
-            help=(
-                "Database provider. All providers except sqlite are considered "
-                "experimental."
-            ),
-            default=_DatabaseProviders.SQLITE,
-        ),
-        click.Option(
-            ["--database-filename"],
-            type=click.Path(file_okay=True, dir_okay=False, path_type=Path),
-            help=("Path to database relative to root."),
-            default=Path(".pytask.sqlite3"),
-            callback=_database_filename_callback,
-        ),
-        click.Option(
-            ["--database-create-db"],
-            type=bool,
-            help="Create database if it does not exist.",
-            default=True,
-        ),
-        click.Option(
-            ["--database-create-tables"],
-            type=bool,
-            help="Create tables if they do not exist.",
-            default=True,
-        ),
-    ]
-    cli.commands["build"].params.extend(additional_parameters)
+from sqlalchemy.engine import make_url
 
 
 @hookimpl
 def pytask_parse_config(config: dict[str, Any]) -> None:
     """Parse the configuration."""
-    if not config["database_filename"].is_absolute():
-        config["database_filename"] = config["root"].joinpath(
-            config["database_filename"]
+    # Set default.
+    if not config["database_url"]:
+        config["database_url"] = make_url(
+            f"sqlite:///{config['root'].as_posix()}/.pytask.sqlite3"
         )
 
-    config["database"] = {
-        "provider": config["database_provider"].value,
-        "filename": config["database_filename"].as_posix(),
-        "create_db": config["database_create_db"],
-        "create_tables": config["database_create_tables"],
-    }
+    if (
+        config["database_url"].drivername == "sqlite"
+        and config["database_url"].database
+    ) and not Path(config["database_url"].database).is_absolute():
+        if config["config"]:
+            full_path = (
+                config["config"]
+                .parent.joinpath(config["database_url"].database)
+                .resolve()
+            )
+        else:
+            full_path = (
+                config["root"].joinpath(config["database_url"].database).resolve()
+            )
+        config["database_url"] = config["database_url"]._replace(
+            database=full_path.as_posix()
+        )
 
 
 @hookimpl
 def pytask_post_parse(config: dict[str, Any]) -> None:
     """Post-parse the configuration."""
-    create_database(**config["database"])
+    create_database(config["database_url"])

src/_pytask/database_utils.py

@@ -6,54 +6,64 @@
 from _pytask.dag_utils import node_and_neighbors
 from _pytask.nodes import Task
 from _pytask.session import Session
-from pony import orm
+from sqlalchemy import Column
+from sqlalchemy import create_engine
+from sqlalchemy import String
+from sqlalchemy.orm import declarative_base
+from sqlalchemy.orm import sessionmaker
 
 
-__all__ = ["create_database", "db", "update_states_in_database"]
+__all__ = ["create_database", "update_states_in_database", "DatabaseSession"]
 
 
-db = orm.Database()
+DatabaseSession = sessionmaker()
 
 
-class State(db.Entity):  # type: ignore[name-defined]
+Base = declarative_base()
+
+
+class State(Base):  # type: ignore[valid-type, misc]
     """Represent the state of a node in relation to a task."""
 
-    task = orm.Required(str)
-    node = orm.Required(str)
-    modification_time = orm.Required(str)
-    file_hash = orm.Optional(str)
+    __tablename__ = "state"
 
-    orm.PrimaryKey(task, node)
+    task = Column(String, primary_key=True)
+    node = Column(String, primary_key=True)
+    modification_time = Column(String)
+    file_hash = Column(String)
 
 
-def create_database(
-    provider: str, filename: str, *, create_db: bool, create_tables: bool
-) -> None:
+def create_database(url: str) -> None:
     """Create the database."""
     try:
-        db.bind(provider=provider, filename=filename, create_db=create_db)
-        db.generate_mapping(create_tables=create_tables)
-    except orm.BindingError:
-        pass
+        engine = create_engine(url)
+        Base.metadata.create_all(bind=engine)
+        DatabaseSession.configure(bind=engine)
+    except Exception:
+        raise
 
 
-@orm.db_session
 def _create_or_update_state(
     first_key: str, second_key: str, modification_time: str, file_hash: str
 ) -> None:
     """Create or update a state."""
-    try:
-        state_in_db = State[first_key, second_key]  # type: ignore[type-arg, valid-type]
-    except orm.ObjectNotFound:
-        State(
-            task=first_key,
-            node=second_key,
-            modification_time=modification_time,
-            file_hash=file_hash,
-        )
-    else:
-        state_in_db.modification_time = modification_time
-        state_in_db.file_hash = file_hash
+    with DatabaseSession() as session:
+        state_in_db = session.get(State, (first_key, second_key))
+
+        if not state_in_db:
+            session.add(
+                State(
+                    task=first_key,
+                    node=second_key,
+                    modification_time=modification_time,
+                    file_hash=file_hash,
+                )
+            )
+        else:
+            state_in_db.modification_time = modification_time
+            state_in_db.file_hash = file_hash
+
+        session.commit()
 
 
 def update_states_in_database(session: Session, task_name: str) -> None:

src/_pytask/parameters.py

@@ -6,6 +6,10 @@
 import click
 from _pytask.config import hookimpl
 from _pytask.config_utils import set_defaults_from_config
+from click import Context
+from sqlalchemy.engine import make_url
+from sqlalchemy.engine import URL
+from sqlalchemy.exc import ArgumentError
 
 
 _CONFIG_OPTION = click.Option(
@@ -67,11 +71,34 @@
 """click.Option: An option to embed URLs in task ids."""
 
 
+def _database_url_callback(
+    ctx: Context, name: str, value: str | None  # noqa: ARG001
+) -> URL:
+    try:
+        return make_url(value)
+    except ArgumentError:
+        raise click.BadParameter(
+            "The 'database_url' must conform to sqlalchemy's url standard: "
+            "https://docs.sqlalchemy.org/en/latest/core/engines.html"
+            "#backend-specific-urls."
+        ) from None
+
+
+_DATABASE_URL_OPTION = click.Option(
+    ["--database-url"],
+    type=str,
+    help=("Url to the database."),
+    default=None,
+    show_default="sqlite:///.../.pytask.sqlite3",
+    callback=_database_url_callback,
+)
+
+
 @hookimpl(trylast=True)
 def pytask_extend_command_line_interface(cli: click.Group) -> None:
     """Register general markers."""
     for command in ("build", "clean", "collect", "dag", "profile"):
-        cli.commands[command].params.append(_PATH_ARGUMENT)
+        cli.commands[command].params.extend([_PATH_ARGUMENT, _DATABASE_URL_OPTION])
     for command in ("build", "clean", "collect", "dag", "markers", "profile"):
         cli.commands[command].params.append(_CONFIG_OPTION)
     for command in ("build", "clean", "collect", "profile"):