Remove dbt-core dependency (#81)

Get rid of the dependency `dbt-core`.

In order to keep the number of dependencies as low as possible, to keep
python environments small, get rid of the dbt-core dependency and add it
to the dev dependencies. This is possible because `dbt-score` only needs
a `manifest.json` in order to run, although `dbt-score` is able to run
`dbt parse` by itself.

---------

Co-authored-by: Matthieu Caneill <[email protected]>

CHANGELOG.md

@@ -8,6 +8,12 @@ and this project adheres to
 
 ## [Unreleased]
 
+- **Breaking**: The rule `public_model_has_example_sql` has been renamed
+  `has_example_sql` and applies by default to all models.
+- **Breaking**: Remove `dbt-core` from dependencies. Since it is not mandatory
+  for `dbt-score` to execute `dbt`, remove the dependency.
+- **Breaking**: Stop using `MultiOption` selection type.
+
 ## [0.6.0] - 2024-08-23
 
 - **Breaking**: Improve error handling in CLI. Log messages are written in

docs/get_started.md

@@ -11,8 +11,8 @@ Installation of `dbt-score` is simple:
 pip install dbt-score
 ```
 
-If a virtual environment is used to run dbt, make sure to install `dbt-score` in
-the same environment.
+In order to run `dbt-score` with all its features, be sure to install
+`dbt-score` in the same environment as `dbt-core`.
 
 ## Usage
 

pyproject.toml

@@ -23,7 +23,6 @@ classifiers = [
 ]
 
 dependencies = [
-    "dbt-core>=1.5",
     "click>=7.1.1, <9.0.0",
     "tomli>=1.1.0; python_version<'3.11'",
 ]
@@ -37,6 +36,7 @@ dbt-score = "dbt_score.__main__:main"
 [tool.pdm]
 [tool.pdm.dev-dependencies]
 dev = [
+    "dbt-core>=1.5",
     "tox-pdm~=0.7.2",
     "tox~=4.13",
 ]

src/dbt_score/cli.py

@@ -7,10 +7,13 @@
 
 import click
 from click.core import ParameterSource
-from dbt.cli.options import MultiOption
 
 from dbt_score.config import Config
-from dbt_score.dbt_utils import DbtParseException, dbt_parse, get_default_manifest_path
+from dbt_score.dbt_utils import (
+    DbtParseException,
+    dbt_parse,
+    get_default_manifest_path,
+)
 from dbt_score.lint import lint_dbt_project
 from dbt_score.rule_catalog import display_catalog
 
@@ -48,8 +51,6 @@ def cli() -> None:
     "--select",
     "-s",
     help="Specify the nodes to include.",
-    cls=MultiOption,
-    type=tuple,
     multiple=True,
 )
 @click.option(

src/dbt_score/dbt_utils.py

@@ -2,10 +2,20 @@
 
 import contextlib
 import os
+from functools import wraps
 from pathlib import Path
-from typing import Iterable, Iterator, cast
+from typing import Any, Callable, Iterable, Iterator, cast
 
-from dbt.cli.main import dbtRunner, dbtRunnerResult
+# Conditionally import dbt objects.
+try:
+    DBT_INSTALLED = True
+    from dbt.cli.main import dbtRunner, dbtRunnerResult  # type: ignore
+except ImportError:
+    DBT_INSTALLED = False
+
+
+class DbtNotInstalledException(Exception):
+    """Raised when trying to run dbt when dbt is not installed."""
 
 
 class DbtParseException(Exception):
@@ -16,13 +26,29 @@ class DbtLsException(Exception):
     """Raised when dbt ls fails."""
 
 
+def dbt_required(func: Callable[..., Any]) -> Callable[..., Any]:
+    """Decorator for methods that require dbt to be installed."""
+
+    @wraps(func)
+    def wrapper(*args: Any, **kwargs: Any) -> Any:
+        if not DBT_INSTALLED:
+            raise DbtNotInstalledException(
+                "This option requires dbt to be installed in the same Python"
+                "environment as dbt-score."
+            )
+        return func(*args, **kwargs)
+
+    return wrapper
+
+
 @contextlib.contextmanager
 def _disable_dbt_stdout() -> Iterator[None]:
     with contextlib.redirect_stdout(None):
         yield
 
 
-def dbt_parse() -> dbtRunnerResult:
+@dbt_required
+def dbt_parse() -> "dbtRunnerResult":
     """Parse a dbt project.
 
     Returns:
@@ -32,22 +58,23 @@ def dbt_parse() -> dbtRunnerResult:
         DbtParseException: dbt parse failed.
     """
     with _disable_dbt_stdout():
-        result: dbtRunnerResult = dbtRunner().invoke(["parse"])
+        result: "dbtRunnerResult" = dbtRunner().invoke(["parse"])
 
     if not result.success:
         raise DbtParseException("dbt parse failed.") from result.exception
 
     return result
 
 
+@dbt_required
 def dbt_ls(select: Iterable[str] | None) -> Iterable[str]:
     """Run dbt ls."""
     cmd = ["ls", "--resource-type", "model", "--output", "name"]
     if select:
         cmd += ["--select", *select]
 
     with _disable_dbt_stdout():
-        result: dbtRunnerResult = dbtRunner().invoke(cmd)
+        result: "dbtRunnerResult" = dbtRunner().invoke(cmd)
 
     if not result.success:
         raise DbtLsException("dbt ls failed.") from result.exception

tests/test_cli.py

@@ -59,6 +59,25 @@ def test_lint_dbt_parse_exception(caplog):
     assert "dbt failed to parse project" in caplog.text
 
 
+def test_lint_dbt_not_installed(caplog, manifest_path):
+    """Test lint with a valid manifest when dbt is not installed."""
+    runner = CliRunner()
+
+    with patch("dbt_score.dbt_utils.DBT_INSTALLED", new=False):
+        result = runner.invoke(lint, ["-m", manifest_path], catch_exceptions=False)
+    assert result.exit_code == 0
+
+
+def test_lint_dbt_not_installed_v(caplog):
+    """Test lint with dbt parse when dbt is not installed."""
+    runner = CliRunner()
+
+    with patch("dbt_score.dbt_utils.DBT_INSTALLED", new=False):
+        result = runner.invoke(lint, ["-p"])
+    assert result.exit_code == 2
+    assert "DbtNotInstalledException" in caplog.text
+
+
 def test_lint_other_exception(manifest_path, caplog):
     """Test lint with an unexpected error."""
     runner = CliRunner()