feat: add proper optional-dependencies for each modules (#75)

README.md

@@ -20,20 +20,42 @@ FastAPI Toolsets provides production-ready utilities for FastAPI applications bu
 
 ## Installation
 
+The base package includes the core modules (CRUD, database, schemas, exceptions, fixtures, dependencies, logging):
+
 ```bash
 uv add fastapi-toolsets
 ```
 
+Install only the extras you need:
+
+```bash
+uv add "fastapi-toolsets[cli]"      # CLI (typer)
+uv add "fastapi-toolsets[metrics]"  # Prometheus metrics (prometheus_client)
+uv add "fastapi-toolsets[pytest]"   # Pytest helpers (httpx, pytest-xdist)
+```
+
+Or install everything:
+
+```bash
+uv add "fastapi-toolsets[all]"
+```
+
 ## Features
 
+### Core
+
 - **CRUD**: Generic async CRUD operations with `CrudFactory`, built-in search with relationship traversal
 - **Database**: Session management, transaction helpers, table locking, and polling-based row change detection
 - **Dependencies**: FastAPI dependency factories (`PathDependency`, `BodyDependency`) for automatic DB lookups from path or body parameters
 - **Fixtures**: Fixture system with dependency management, context support, and pytest integration
-- **CLI**: Django-like command-line interface with fixture management and custom commands support
 - **Standardized API Responses**: Consistent response format with `Response`, `PaginatedResponse`, and `PydanticBase`
 - **Exception Handling**: Structured error responses with automatic OpenAPI documentation
 - **Logging**: Logging configuration with uvicorn integration via `configure_logging` and `get_logger`
+
+### Optional
+
+- **CLI**: Django-like command-line interface with fixture management and custom commands support
+- **Metrics**: Prometheus metrics endpoint with provider/collector registry
 - **Pytest Helpers**: Async test client, database session management, `pytest-xdist` support, and table cleanup utilities
 
 ## License

pyproject.toml

@@ -31,12 +31,10 @@ classifiers = [
     "Typing :: Typed",
 ]
 dependencies = [
-    "fastapi>=0.100.0",
-    "sqlalchemy[asyncio]>=2.0",
     "asyncpg>=0.29.0",
+    "fastapi>=0.100.0",
     "pydantic>=2.0",
-    "typer>=0.9.0",
+    "sqlalchemy[asyncio]>=2.0",
-    "httpx>=0.25.0",
 ]
 
 [project.urls]
@@ -46,18 +44,28 @@ Repository = "https://github.com/d3vyce/fastapi-toolsets"
 Issues = "https://github.com/d3vyce/fastapi-toolsets/issues"
 
 [project.optional-dependencies]
+cli = [
+    "typer>=0.9.0",
+]
 metrics = [
     "prometheus_client>=0.20.0",
 ]
-test = [
+pytest = [
-    "pytest>=8.0.0",
+    "httpx>=0.25.0",
-    "pytest-anyio>=0.0.0",
     "pytest-xdist>=3.0.0",
+    "pytest>=8.0.0",
+]
+all = [
+    "fastapi-toolsets[cli,metrics,pytest]",
+]
+test = [
     "coverage>=7.0.0",
+    "fastapi-toolsets[pytest]",
+    "pytest-anyio>=0.0.0",
     "pytest-cov>=4.0.0",
 ]
 dev = [
-    "fastapi-toolsets[metrics,test]",
+    "fastapi-toolsets[all,test]",
     "ruff>=0.1.0",
     "ty>=0.0.1a0",
 ]

src/fastapi_toolsets/_imports.py

@@ -0,0 +1,9 @@
+"""Optional dependency helpers."""
+
+
+def require_extra(package: str, extra: str) -> None:
+    """Raise *ImportError* with an actionable install instruction."""
+    raise ImportError(
+        f"'{package}' is required to use this module. "
+        f"Install it with: pip install fastapi-toolsets[{extra}]"
+    )

src/fastapi_toolsets/cli/app.py

@@ -1,6 +1,11 @@
 """Main CLI application."""
 
-import typer
+try:
+    import typer
+except ImportError:
+    from .._imports import require_extra
+
+    require_extra(package="typer", extra="cli")
 
 from ..logger import configure_logging
 from .config import get_custom_cli

src/fastapi_toolsets/metrics/__init__.py

@@ -1,8 +1,19 @@
 """Prometheus metrics integration for FastAPI applications."""
 
-from .handler import init_metrics
+from typing import Any
+
 from .registry import Metric, MetricsRegistry
 
+try:
+    from .handler import init_metrics
+except ImportError:
+
+    def init_metrics(*_args: Any, **_kwargs: Any) -> None:
+        from .._imports import require_extra
+
+        require_extra(package="prometheus_client", extra="metrics")
+
+
 __all__ = [
     "Metric",
     "MetricsRegistry",

src/fastapi_toolsets/pytest/__init__.py

@@ -1,13 +1,24 @@
 """Pytest helpers for FastAPI testing: sessions, clients, and fixtures."""
 
-from .plugin import register_fixtures
+try:
-from .utils import (
+    from .plugin import register_fixtures
-    cleanup_tables,
+except ImportError:
-    create_async_client,
+    from .._imports import require_extra
-    create_db_session,
+
-    create_worker_database,
+    require_extra(package="pytest", extra="pytest")
-    worker_database_url,
+
-)
+try:
+    from .utils import (
+        cleanup_tables,
+        create_async_client,
+        create_db_session,
+        create_worker_database,
+        worker_database_url,
+    )
+except ImportError:
+    from .._imports import require_extra
+
+    require_extra(package="httpx", extra="pytest")
 
 __all__ = [
     "cleanup_tables",

tests/test_imports.py

@@ -0,0 +1,229 @@
+"""Tests for optional dependency import guards."""
+
+import importlib
+import sys
+from unittest.mock import patch
+
+import pytest
+
+from fastapi_toolsets._imports import require_extra
+
+
+class TestRequireExtra:
+    """Tests for the require_extra helper."""
+
+    def test_raises_import_error(self):
+        """require_extra raises ImportError."""
+        with pytest.raises(ImportError):
+            require_extra(package="some_pkg", extra="some_extra")
+
+    def test_error_message_contains_package_name(self):
+        """Error message mentions the missing package."""
+        with pytest.raises(ImportError, match="'prometheus_client'"):
+            require_extra(package="prometheus_client", extra="metrics")
+
+    def test_error_message_contains_install_instruction(self):
+        """Error message contains the pip install command."""
+        with pytest.raises(
+            ImportError, match=r"pip install fastapi-toolsets\[metrics\]"
+        ):
+            require_extra(package="prometheus_client", extra="metrics")
+
+
+def _reload_without_package(module_path: str, blocked_packages: list[str]):
+    """Reload a module while blocking specific package imports.
+
+    Removes the target module and its parents from sys.modules so they
+    get re-imported, and patches builtins.__import__ to raise ImportError
+    for *blocked_packages*.
+    """
+    # Remove cached modules so they get re-imported
+    to_remove = [
+        key
+        for key in sys.modules
+        if key == module_path or key.startswith(module_path + ".")
+    ]
+    saved = {}
+    for key in to_remove:
+        saved[key] = sys.modules.pop(key)
+
+    # Also remove parent package to force re-execution of __init__.py
+    parts = module_path.rsplit(".", 1)
+    if len(parts) == 2:
+        parent = parts[0]
+        parent_keys = [
+            key for key in sys.modules if key == parent or key.startswith(parent + ".")
+        ]
+        for key in parent_keys:
+            if key not in saved:
+                saved[key] = sys.modules.pop(key)
+
+    original_import = (
+        __builtins__.__import__ if hasattr(__builtins__, "__import__") else __import__
+    )
+
+    def blocking_import(name, *args, **kwargs):
+        for blocked in blocked_packages:
+            if name == blocked or name.startswith(blocked + "."):
+                raise ImportError(f"Mocked: No module named '{name}'")
+        return original_import(name, *args, **kwargs)
+
+    return saved, blocking_import
+
+
+class TestMetricsImportGuard:
+    """Tests for metrics module import guard when prometheus_client is missing."""
+
+    def test_registry_imports_without_prometheus(self):
+        """Metric and MetricsRegistry are importable without prometheus_client."""
+        saved, blocking_import = _reload_without_package(
+            "fastapi_toolsets.metrics", ["prometheus_client"]
+        )
+        try:
+            with patch("builtins.__import__", side_effect=blocking_import):
+                mod = importlib.import_module("fastapi_toolsets.metrics")
+                # Registry types should be available (they're stdlib-only)
+                assert hasattr(mod, "Metric")
+                assert hasattr(mod, "MetricsRegistry")
+        finally:
+            # Restore original modules
+            for key in list(sys.modules):
+                if key.startswith("fastapi_toolsets.metrics"):
+                    sys.modules.pop(key, None)
+            sys.modules.update(saved)
+
+    def test_init_metrics_stub_raises_without_prometheus(self):
+        """init_metrics raises ImportError when prometheus_client is missing."""
+        saved, blocking_import = _reload_without_package(
+            "fastapi_toolsets.metrics", ["prometheus_client"]
+        )
+        try:
+            with patch("builtins.__import__", side_effect=blocking_import):
+                mod = importlib.import_module("fastapi_toolsets.metrics")
+                with pytest.raises(ImportError, match="prometheus_client"):
+                    mod.init_metrics(None, None)  # type: ignore[arg-type]
+        finally:
+            for key in list(sys.modules):
+                if key.startswith("fastapi_toolsets.metrics"):
+                    sys.modules.pop(key, None)
+            sys.modules.update(saved)
+
+    def test_init_metrics_works_with_prometheus(self):
+        """init_metrics is the real function when prometheus_client is available."""
+        from fastapi_toolsets.metrics import init_metrics
+
+        # Should be the real function, not a stub
+        assert init_metrics.__module__ == "fastapi_toolsets.metrics.handler"
+
+
+class TestPytestImportGuard:
+    """Tests for pytest module import guard when dependencies are missing."""
+
+    def test_import_raises_without_pytest_package(self):
+        """Importing fastapi_toolsets.pytest raises when pytest is missing."""
+        saved, blocking_import = _reload_without_package(
+            "fastapi_toolsets.pytest", ["pytest"]
+        )
+        try:
+            with patch("builtins.__import__", side_effect=blocking_import):
+                with pytest.raises(ImportError, match="pytest"):
+                    importlib.import_module("fastapi_toolsets.pytest")
+        finally:
+            for key in list(sys.modules):
+                if key.startswith("fastapi_toolsets.pytest"):
+                    sys.modules.pop(key, None)
+            sys.modules.update(saved)
+
+    def test_import_raises_without_httpx(self):
+        """Importing fastapi_toolsets.pytest raises when httpx is missing."""
+        saved, blocking_import = _reload_without_package(
+            "fastapi_toolsets.pytest", ["httpx"]
+        )
+        try:
+            with patch("builtins.__import__", side_effect=blocking_import):
+                with pytest.raises(ImportError, match="httpx"):
+                    importlib.import_module("fastapi_toolsets.pytest")
+        finally:
+            for key in list(sys.modules):
+                if key.startswith("fastapi_toolsets.pytest"):
+                    sys.modules.pop(key, None)
+            sys.modules.update(saved)
+
+    def test_all_exports_available_with_deps(self):
+        """All expected exports are available when deps are installed."""
+        from fastapi_toolsets.pytest import (
+            cleanup_tables,
+            create_async_client,
+            create_db_session,
+            create_worker_database,
+            register_fixtures,
+            worker_database_url,
+        )
+
+        assert callable(register_fixtures)
+        assert callable(create_async_client)
+        assert callable(create_db_session)
+        assert callable(create_worker_database)
+        assert callable(worker_database_url)
+        assert callable(cleanup_tables)
+
+
+class TestCliImportGuard:
+    """Tests for CLI module import guard when typer is missing."""
+
+    def test_import_raises_without_typer(self):
+        """Importing cli.app raises when typer is missing."""
+        saved, blocking_import = _reload_without_package(
+            "fastapi_toolsets.cli.app", ["typer"]
+        )
+        # Also remove cli.config since it imports typer too
+        config_keys = [
+            k for k in sys.modules if k.startswith("fastapi_toolsets.cli.config")
+        ]
+        for key in config_keys:
+            if key not in saved:
+                saved[key] = sys.modules.pop(key)
+
+        try:
+            with patch("builtins.__import__", side_effect=blocking_import):
+                with pytest.raises(ImportError, match="typer"):
+                    importlib.import_module("fastapi_toolsets.cli.app")
+        finally:
+            for key in list(sys.modules):
+                if key.startswith("fastapi_toolsets.cli.app") or key.startswith(
+                    "fastapi_toolsets.cli.config"
+                ):
+                    sys.modules.pop(key, None)
+            sys.modules.update(saved)
+
+    def test_error_message_suggests_cli_extra(self):
+        """Error message suggests installing the cli extra."""
+        saved, blocking_import = _reload_without_package(
+            "fastapi_toolsets.cli.app", ["typer"]
+        )
+        config_keys = [
+            k for k in sys.modules if k.startswith("fastapi_toolsets.cli.config")
+        ]
+        for key in config_keys:
+            if key not in saved:
+                saved[key] = sys.modules.pop(key)
+
+        try:
+            with patch("builtins.__import__", side_effect=blocking_import):
+                with pytest.raises(
+                    ImportError, match=r"pip install fastapi-toolsets\[cli\]"
+                ):
+                    importlib.import_module("fastapi_toolsets.cli.app")
+        finally:
+            for key in list(sys.modules):
+                if key.startswith("fastapi_toolsets.cli.app") or key.startswith(
+                    "fastapi_toolsets.cli.config"
+                ):
+                    sys.modules.pop(key, None)
+            sys.modules.update(saved)
+
+    def test_async_command_imports_without_typer(self):
+        """async_command is importable without typer (stdlib only)."""
+        from fastapi_toolsets.cli import async_command
+
+        assert callable(async_command)

uv.lock

@@ -245,17 +245,30 @@ name = "fastapi-toolsets"
 version = "0.10.0"
 source = { editable = "." }
 dependencies = [
-    { name = "asyncpg" },
     { name = "fastapi" },
-    { name = "httpx" },
     { name = "pydantic" },
     { name = "sqlalchemy", extra = ["asyncio"] },
-    { name = "typer" },
 ]
 
 [package.optional-dependencies]
+all = [
+    { name = "asyncpg" },
+    { name = "httpx" },
+    { name = "prometheus-client" },
+    { name = "pytest" },
+    { name = "pytest-xdist" },
+    { name = "typer" },
+]
+asyncpg = [
+    { name = "asyncpg" },
+]
+cli = [
+    { name = "typer" },
+]
 dev = [
+    { name = "asyncpg" },
     { name = "coverage" },
+    { name = "httpx" },
     { name = "prometheus-client" },
     { name = "pytest" },
     { name = "pytest-anyio" },
@@ -263,12 +276,19 @@ dev = [
     { name = "pytest-xdist" },
     { name = "ruff" },
     { name = "ty" },
+    { name = "typer" },
 ]
 metrics = [
     { name = "prometheus-client" },
 ]
+pytest = [
+    { name = "httpx" },
+    { name = "pytest" },
+    { name = "pytest-xdist" },
+]
 test = [
     { name = "coverage" },
+    { name = "httpx" },
     { name = "pytest" },
     { name = "pytest-anyio" },
     { name = "pytest-cov" },
@@ -277,23 +297,25 @@ test = [
 
 [package.metadata]
 requires-dist = [
-    { name = "asyncpg", specifier = ">=0.29.0" },
+    { name = "asyncpg", marker = "extra == 'asyncpg'", specifier = ">=0.29.0" },
     { name = "coverage", marker = "extra == 'test'", specifier = ">=7.0.0" },
     { name = "fastapi", specifier = ">=0.100.0" },
-    { name = "fastapi-toolsets", extras = ["metrics", "test"], marker = "extra == 'dev'" },
+    { name = "fastapi-toolsets", extras = ["all", "test"], marker = "extra == 'dev'" },
-    { name = "httpx", specifier = ">=0.25.0" },
+    { name = "fastapi-toolsets", extras = ["asyncpg", "cli", "metrics", "pytest"], marker = "extra == 'all'" },
+    { name = "fastapi-toolsets", extras = ["pytest"], marker = "extra == 'test'" },
+    { name = "httpx", marker = "extra == 'pytest'", specifier = ">=0.25.0" },
     { name = "prometheus-client", marker = "extra == 'metrics'", specifier = ">=0.20.0" },
     { name = "pydantic", specifier = ">=2.0" },
-    { name = "pytest", marker = "extra == 'test'", specifier = ">=8.0.0" },
+    { name = "pytest", marker = "extra == 'pytest'", specifier = ">=8.0.0" },
     { name = "pytest-anyio", marker = "extra == 'test'", specifier = ">=0.0.0" },
     { name = "pytest-cov", marker = "extra == 'test'", specifier = ">=4.0.0" },
-    { name = "pytest-xdist", marker = "extra == 'test'", specifier = ">=3.0.0" },
+    { name = "pytest-xdist", marker = "extra == 'pytest'", specifier = ">=3.0.0" },
     { name = "ruff", marker = "extra == 'dev'", specifier = ">=0.1.0" },
     { name = "sqlalchemy", extras = ["asyncio"], specifier = ">=2.0" },
     { name = "ty", marker = "extra == 'dev'", specifier = ">=0.0.1a0" },
-    { name = "typer", specifier = ">=0.9.0" },
+    { name = "typer", marker = "extra == 'cli'", specifier = ">=0.9.0" },
 ]
-provides-extras = ["metrics", "test", "dev"]
+provides-extras = ["asyncpg", "cli", "metrics", "pytest", "all", "test", "dev"]
 
 [[package]]
 name = "greenlet"