Initial commit

.gitignore

@@ -0,0 +1,161 @@
+# Byte-compiled / optimized / DLL files
+__pycache__/
+*.py[cod]
+*$py.class
+
+# C extensions
+*.so
+
+# Distribution / packaging
+.Python
+Pipfile
+build/
+develop-eggs/
+dist/
+downloads/
+eggs/
+.eggs/
+lib/
+lib64/
+parts/
+sdist/
+var/
+wheels/
+share/python-wheels/
+*.egg-info/
+.installed.cfg
+*.egg
+MANIFEST
+
+# PyInstaller
+#  Usually these files are written by a python script from a template
+#  before PyInstaller builds the exe, so as to inject date/other infos into it.
+*.manifest
+*.spec
+
+# Installer logs
+pip-log.txt
+pip-delete-this-directory.txt
+
+# Unit test / coverage reports
+htmlcov/
+.tox/
+.nox/
+.coverage
+.coverage.*
+.cache
+nosetests.xml
+coverage.xml
+*.cover
+*.py,cover
+.hypothesis/
+.pytest_cache/
+cover/
+
+# Translations
+*.mo
+*.pot
+
+# Django stuff:
+*.log
+local_settings.py
+db.sqlite3
+db.sqlite3-journal
+
+# Flask stuff:
+instance/
+.webassets-cache
+
+# Scrapy stuff:
+.scrapy
+
+# Sphinx documentation
+docs/_build/
+
+# PyBuilder
+.pybuilder/
+target/
+
+# Jupyter Notebook
+.ipynb_checkpoints
+
+# IPython
+profile_default/
+ipython_config.py
+
+# pyenv
+#   For a library or package, you might want to ignore these files since the code is
+#   intended to run in multiple environments; otherwise, check them in:
+# .python-version
+
+# pipenv
+#   According to pypa/pipenv#598, it is recommended to include Pipfile.lock in version control.
+#   However, in case of collaboration, if having platform-specific dependencies or dependencies
+#   having no cross-platform support, pipenv may install dependencies that don't work, or not
+#   install all needed dependencies.
+#Pipfile.lock
+
+# poetry
+#   Similar to Pipfile.lock, it is generally recommended to include poetry.lock in version control.
+#   This is especially recommended for binary packages to ensure reproducibility, and is more
+#   commonly ignored for libraries.
+#   https://python-poetry.org/docs/basic-usage/#commit-your-poetrylock-file-to-version-control
+#poetry.lock
+
+# pdm
+#   Similar to Pipfile.lock, it is generally recommended to include pdm.lock in version control.
+#pdm.lock
+#   pdm stores project-wide configurations in .pdm.toml, but it is recommended to not include it
+#   in version control.
+#   https://pdm.fming.dev/#use-with-ide
+.pdm.toml
+
+# PEP 582; used by e.g. github.com/David-OConnor/pyflow and github.com/pdm-project/pdm
+__pypackages__/
+
+# Celery stuff
+celerybeat-schedule
+celerybeat.pid
+
+# SageMath parsed files
+*.sage.py
+
+# Environments
+.env
+.venv
+env/
+venv/
+ENV/
+env.bak/
+venv.bak/
+
+# Spyder project settings
+.spyderproject
+.spyproject
+
+# Rope project settings
+.ropeproject
+
+# mkdocs documentation
+/site
+
+# mypy
+.mypy_cache/
+.dmypy.json
+dmypy.json
+
+# Pyre type checker
+.pyre/
+
+# pytype static type analyzer
+.pytype/
+
+# Cython debug symbols
+cython_debug/
+
+# PyCharm
+#  JetBrains specific template is maintained in a separate JetBrains.gitignore that can
+#  be found at https://github.com/github/gitignore/blob/main/Global/JetBrains.gitignore
+#  and can be added to the global gitignore or merged into this file.  For a more nuclear
+#  option (not recommended) you can uncomment the following to ignore the entire idea folder.
+#.idea/

LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2023 Ted Conbeer
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

@@ -0,0 +1,4 @@
+# harlequin-adapter-template
+This repo provides a template you can use to accelerate development of a new [Harlequin](https://harlequin.sh) database adapter.
+
+For an in-depth guide on writing your own adapter, see the [Harlequin Docs](https://harlequin.sh/docs/contributing/adapter-guide).

pyproject.toml

@@ -0,0 +1,64 @@
+[tool.poetry]
+name = "harlequin_myadapter"
+version = "0.1.0"
+description = "A Harlequin adapter for <my favorite database>."
+authors = ["Ted Conbeer <tconbeer@users.noreply.github.com>"]
+license = "MIT"
+readme = "README.md"
+packages = [
+    { include = "harlequin_myadapter", from = "src" },
+]
+
+[tool.poetry.plugins."harlequin.adapter"]
+my-adapter = "harlequin_myadapter:MyAdapter"
+
+[tool.poetry.dependencies]
+python = ">=3.8.1,<4.0"
+harlequin = "^1.7"
+
+[tool.poetry.group.dev.dependencies]
+ruff = "^0.1.6"
+pytest = "^7.4.3"
+mypy = "^1.7.0"
+pre-commit = "^3.5.0"
+importlib_metadata = { version = ">=4.6.0", python = "<3.10.0" }
+
+[build-system]
+requires = ["poetry-core"]
+build-backend = "poetry.core.masonry.api"
+
+
+[tool.ruff]
+select = ["A", "B", "E", "F", "I"]
+target-version = "py38"
+
+[tool.mypy]
+python_version = "3.8"
+files = [
+    "src/**/*.py",
+    "tests/**/*.py",
+]
+mypy_path = "src:stubs"
+
+show_column_numbers = true
+
+# show error messages from unrelated files
+follow_imports = "normal"
+
+# be strict
+disallow_untyped_calls = true
+disallow_untyped_defs = true
+check_untyped_defs = true
+disallow_untyped_decorators = true
+disallow_incomplete_defs = true
+disallow_subclassing_any = true
+strict_optional = true
+
+warn_return_any = true
+warn_no_return = true
+warn_redundant_casts = true
+warn_unused_ignores = true
+warn_unused_configs = true
+
+no_implicit_reexport = true
+strict_equality = true

src/harlequin_myadapter/__init__.py

@@ -0,0 +1,3 @@
+from harlequin_myadapter.adapter import MyAdapter
+
+__all__ = ["MyAdapter"]

src/harlequin_myadapter/adapter.py

@@ -0,0 +1,139 @@
+from __future__ import annotations
+
+from typing import Any, Sequence
+
+from harlequin import (
+    HarlequinAdapter,
+    HarlequinConnection,
+    HarlequinCursor,
+)
+from harlequin.autocomplete.completion import HarlequinCompletion
+from harlequin.catalog import Catalog, CatalogItem
+from harlequin.exception import HarlequinConnectionError, HarlequinQueryError
+from textual_fastdatatable.backend import AutoBackendType
+
+from harlequin_myadapter.cli_options import MYADAPTER_OPTIONS
+
+
+class MyCursor(HarlequinCursor):
+    def __init__(self, *args: Any, **kwargs: Any) -> None:
+        self.cur = args[0]
+        self._limit: int | None = None
+
+    def columns(self) -> list[tuple[str, str]]:
+        names = self.cur.column_names
+        types = self.cur.column_types
+        return list(zip(names, types))
+
+    def set_limit(self, limit: int) -> MyCursor:
+        self._limit = limit
+        return self
+
+    def fetchall(self) -> AutoBackendType:
+        try:
+            if self._limit is None:
+                return self.cur.fetchall()
+            else:
+                return self.cur.fetchmany(self._limit)
+        except Exception as e:
+            raise HarlequinQueryError(
+                msg=str(e),
+                title="Harlequin encountered an error while executing your query.",
+            ) from e
+
+
+class MyConnection(HarlequinConnection):
+    def __init__(
+        self, conn_str: Sequence[str], *args: Any, init_message: str = "", **kwargs: Any
+    ) -> None:
+        self.init_message = init_message
+        try:
+            self.conn = "your database library's connect method goes here"
+        except Exception as e:
+            raise HarlequinConnectionError(
+                msg=str(e), title="Harlequin could not connect to your database."
+            ) from e
+
+    def execute(self, query: str) -> HarlequinCursor | None:
+        try:
+            cur = self.conn.execute(query)  # type: ignore
+        except Exception as e:
+            raise HarlequinQueryError(
+                msg=str(e),
+                title="Harlequin encountered an error while executing your query.",
+            ) from e
+        else:
+            if cur is not None:
+                return MyCursor(cur)
+            else:
+                return None
+
+    def get_catalog(self) -> Catalog:
+        databases = self.conn.list_databases()
+        db_items: list[CatalogItem] = []
+        for db in databases:
+            schemas = self.conn.list_schemas_in_db(db)
+            schema_items: list[CatalogItem] = []
+            for schema in schemas:
+                relations = self.conn.list_relations_in_schema(schema)
+                rel_items: list[CatalogItem] = []
+                for rel, rel_type in relations:
+                    cols = self.conn.list_columns_in_relation(rel)
+                    col_items = [
+                        CatalogItem(
+                            qualified_identifier=f'"{db}"."{schema}"."{rel}"."{col}"',
+                            query_name=f'"{col}"',
+                            label=col,
+                            type_label=col_type,
+                        )
+                        for col, col_type in cols
+                    ]
+                    rel_items.append(
+                        CatalogItem(
+                            qualified_identifier=f'"{db}"."{schema}"."{rel}"',
+                            query_name=f'"{db}"."{schema}"."{rel}"',
+                            label=rel,
+                            type_label=rel_type,
+                            children=col_items,
+                        )
+                    )
+                schema_items.append(
+                    CatalogItem(
+                        qualified_identifier=f'"{db}"."{schema}"',
+                        query_name=f'"{db}"."{schema}"',
+                        label=schema,
+                        type_label="s",
+                        children=rel_items,
+                    )
+                )
+            db_items.append(
+                CatalogItem(
+                    qualified_identifier=f'"{db}"',
+                    query_name=f'"{db}"',
+                    label=db,
+                    type_label="db",
+                    children=schema_items,
+                )
+            )
+        return Catalog(items=db_items)
+
+    def get_completions(self) -> list[HarlequinCompletion]:
+        extra_keywords = ["foo", "bar", "baz"]
+        return [
+            HarlequinCompletion(
+                label=item, type_label="kw", value=item, priority=1000, context=None
+            )
+            for item in extra_keywords
+        ]
+
+
+class MyAdapter(HarlequinAdapter):
+    ADAPTER_OPTIONS = MYADAPTER_OPTIONS
+
+    def __init__(self, conn_str: Sequence[str], **options: Any) -> None:
+        self.conn_str = conn_str
+        self.options = options
+
+    def connect(self) -> MyConnection:
+        conn = MyConnection(self.conn_str, self.options)
+        return conn

src/harlequin_myadapter/cli_options.py

@@ -0,0 +1,15 @@
+from harlequin.options import (
+    FlagOption,  # noqa
+    ListOption,  # noqa
+    PathOption,  # noqa
+    SelectOption,  # noqa
+    TextOption,
+)
+
+foo = TextOption(
+    name="foo",
+    description="Help text goes here",
+    short_decls=["-f"],
+)
+
+MYADAPTER_OPTIONS = [foo]

tests/test_adapter.py

@@ -0,0 +1,89 @@
+import sys
+
+import pytest
+from harlequin.adapter import HarlequinAdapter, HarlequinConnection, HarlequinCursor
+from harlequin.catalog import Catalog, CatalogItem
+from harlequin.exception import HarlequinConnectionError, HarlequinQueryError
+from harlequin_myadapter.adapter import MyAdapter, MyConnection
+from textual_fastdatatable.backend import create_backend
+
+if sys.version_info < (3, 10):
+    from importlib_metadata import entry_points
+else:
+    from importlib.metadata import entry_points
+
+
+def test_plugin_discovery() -> None:
+    PLUGIN_NAME = "my-adapter"
+    eps = entry_points(group="harlequin.adapter")
+    assert eps[PLUGIN_NAME]
+    adapter_cls = eps[PLUGIN_NAME].load()
+    assert issubclass(adapter_cls, HarlequinAdapter)
+    assert adapter_cls == MyAdapter
+
+
+def test_connect() -> None:
+    conn = MyAdapter(conn_str=tuple()).connect()
+    assert isinstance(conn, HarlequinConnection)
+
+
+def test_init_extra_kwargs() -> None:
+    assert MyAdapter(conn_str=tuple(), foo=1, bar="baz").connect()
+
+
+def test_connect_raises_connection_error() -> None:
+    with pytest.raises(HarlequinConnectionError):
+        _ = MyAdapter(conn_str=("foo",)).connect()
+
+
+@pytest.fixture
+def connection() -> MyConnection:
+    return MyAdapter(conn_str=tuple()).connect()
+
+
+def test_get_catalog(connection: MyConnection) -> None:
+    catalog = connection.get_catalog()
+    assert isinstance(catalog, Catalog)
+    assert catalog.items
+    assert isinstance(catalog.items[0], CatalogItem)
+
+
+def test_execute_ddl(connection: MyConnection) -> None:
+    cur = connection.execute("create table foo (a int)")
+    assert cur is None
+
+
+def test_execute_select(connection: MyConnection) -> None:
+    cur = connection.execute("select 1 as a")
+    assert isinstance(cur, HarlequinCursor)
+    assert cur.columns() == [("a", "##")]
+    data = cur.fetchall()
+    backend = create_backend(data)
+    assert backend.column_count == 1
+    assert backend.row_count == 1
+
+
+def test_execute_select_dupe_cols(connection: MyConnection) -> None:
+    cur = connection.execute("select 1 as a, 2 as a, 3 as a")
+    assert isinstance(cur, HarlequinCursor)
+    assert len(cur.columns()) == 3
+    data = cur.fetchall()
+    backend = create_backend(data)
+    assert backend.column_count == 3
+    assert backend.row_count == 1
+
+
+def test_set_limit(connection: MyConnection) -> None:
+    cur = connection.execute("select 1 as a union all select 2 union all select 3")
+    assert isinstance(cur, HarlequinCursor)
+    cur = cur.set_limit(2)
+    assert isinstance(cur, HarlequinCursor)
+    data = cur.fetchall()
+    backend = create_backend(data)
+    assert backend.column_count == 1
+    assert backend.row_count == 2
+
+
+def test_execute_raises_query_error(connection: MyConnection) -> None:
+    with pytest.raises(HarlequinQueryError):
+        _ = connection.execute("selec;")