check if required packages are installed for instruments and bootstrappers

lite_bootstrap/bootstrappers/base.py

@@ -1,5 +1,6 @@
 import abc
 import typing
+import warnings
 
 from lite_bootstrap.instruments.base import BaseConfig, BaseInstrument
 from lite_bootstrap.types import ApplicationT
@@ -14,16 +15,28 @@ class BaseBootstrapper(abc.ABC, typing.Generic[ApplicationT]):
     bootstrap_config: BaseConfig
 
     def __init__(self, bootstrap_config: BaseConfig) -> None:
+        if not self.is_ready():
+            raise RuntimeError(self.not_ready_message)
+
         self.bootstrap_config = bootstrap_config
         self.instruments = []
         for instrument_type in self.instruments_types:
             instrument = instrument_type(bootstrap_config=bootstrap_config)
             if instrument.is_ready():
                 self.instruments.append(instrument)
+            else:
+                warnings.warn(instrument.not_ready_message, stacklevel=2)
+
+    @property
+    @abc.abstractmethod
+    def not_ready_message(self) -> str: ...
 
     @abc.abstractmethod
     def _prepare_application(self) -> ApplicationT: ...
 
+    @abc.abstractmethod
+    def is_ready(self) -> bool: ...
+
     def bootstrap(self) -> ApplicationT:
         for one_instrument in self.instruments:
             one_instrument.bootstrap()

lite_bootstrap/bootstrappers/fastapi_bootstrapper.py

@@ -1,7 +1,7 @@
-import contextlib
 import dataclasses
 import typing
 
+from lite_bootstrap import import_checker
 from lite_bootstrap.bootstrappers.base import BaseBootstrapper
 from lite_bootstrap.instruments.healthchecks_instrument import (
     HealthChecksConfig,
@@ -14,16 +14,20 @@
 from lite_bootstrap.instruments.sentry_instrument import SentryConfig, SentryInstrument
 
 
-with contextlib.suppress(ImportError):
+if import_checker.is_fastapi_installed:
     import fastapi
+
+if import_checker.is_opentelemetry_installed:
     from opentelemetry.instrumentation.fastapi import FastAPIInstrumentor
     from opentelemetry.trace import get_tracer_provider
+
+if import_checker.is_prometheus_fastapi_instrumentator_installed:
     from prometheus_fastapi_instrumentator import Instrumentator
 
 
 @dataclasses.dataclass(kw_only=True, slots=True, frozen=True)
 class FastAPIConfig(HealthChecksConfig, LoggingConfig, OpentelemetryConfig, PrometheusConfig, SentryConfig):
-    application: fastapi.FastAPI = dataclasses.field(default_factory=fastapi.FastAPI)
+    application: "fastapi.FastAPI" = dataclasses.field(default_factory=fastapi.FastAPI)
     opentelemetry_excluded_urls: list[str] = dataclasses.field(default_factory=list)
     prometheus_instrumentator_params: dict[str, typing.Any] = dataclasses.field(default_factory=dict)
     prometheus_instrument_params: dict[str, typing.Any] = dataclasses.field(default_factory=dict)
@@ -34,7 +38,7 @@ class FastAPIConfig(HealthChecksConfig, LoggingConfig, OpentelemetryConfig, Prom
 class FastAPIHealthChecksInstrument(HealthChecksInstrument):
     bootstrap_config: FastAPIConfig
 
-    def build_fastapi_health_check_router(self) -> fastapi.APIRouter:
+    def build_fastapi_health_check_router(self) -> "fastapi.APIRouter":
         fastapi_router = fastapi.APIRouter(
             tags=["probes"],
             include_in_schema=self.bootstrap_config.health_checks_include_in_schema,
@@ -87,6 +91,12 @@ class FastAPISentryInstrument(SentryInstrument):
 @dataclasses.dataclass(kw_only=True, frozen=True)
 class FastAPIPrometheusInstrument(PrometheusInstrument):
     bootstrap_config: FastAPIConfig
+    not_ready_message = (
+        PrometheusInstrument.not_ready_message + " or prometheus_fastapi_instrumentator is not installed"
+    )
+
+    def is_ready(self) -> bool:
+        return super().is_ready() and import_checker.is_prometheus_fastapi_instrumentator_installed
 
     def bootstrap(self) -> None:
         Instrumentator(**self.bootstrap_config.prometheus_instrument_params).instrument(
@@ -101,6 +111,8 @@ def bootstrap(self) -> None:
 
 
 class FastAPIBootstrapper(BaseBootstrapper[fastapi.FastAPI]):
+    __slots__ = "bootstrap_config", "instruments"
+
     instruments_types: typing.ClassVar = [
         FastAPIOpenTelemetryInstrument,
         FastAPISentryInstrument,
@@ -109,7 +121,10 @@ class FastAPIBootstrapper(BaseBootstrapper[fastapi.FastAPI]):
         FastAPIPrometheusInstrument,
     ]
     bootstrap_config: FastAPIConfig
-    __slots__ = "bootstrap_config", "instruments"
+    not_ready_message = "fastapi is not installed"
+
+    def is_ready(self) -> bool:
+        return import_checker.is_fastapi_installed
 
     def _prepare_application(self) -> fastapi.FastAPI:
         return self.bootstrap_config.application

lite_bootstrap/bootstrappers/faststream_bootstrapper.py

@@ -1,9 +1,9 @@
 from __future__ import annotations
-import contextlib
 import dataclasses
 import json
 import typing
 
+from lite_bootstrap import import_checker
 from lite_bootstrap.bootstrappers.base import BaseBootstrapper
 from lite_bootstrap.instruments.healthchecks_instrument import HealthChecksConfig, HealthChecksInstrument
 from lite_bootstrap.instruments.logging_instrument import LoggingConfig, LoggingInstrument
@@ -12,12 +12,16 @@
 from lite_bootstrap.instruments.sentry_instrument import SentryConfig, SentryInstrument
 
 
-with contextlib.suppress(ImportError):
+if import_checker.is_faststream_installed:
     import faststream
-    import prometheus_client
     from faststream.asgi import AsgiFastStream, AsgiResponse
     from faststream.asgi import get as handle_get
     from faststream.broker.core.usecase import BrokerUsecase
+
+if import_checker.is_prometheus_client_installed:
+    import prometheus_client
+
+if import_checker.is_opentelemetry_installed:
     from opentelemetry.metrics import Meter, MeterProvider
     from opentelemetry.trace import TracerProvider, get_tracer_provider
 
@@ -87,9 +91,10 @@ class FastStreamLoggingInstrument(LoggingInstrument):
 @dataclasses.dataclass(kw_only=True, frozen=True)
 class FastStreamOpenTelemetryInstrument(OpenTelemetryInstrument):
     bootstrap_config: FastStreamConfig
+    not_ready_message = OpenTelemetryInstrument.not_ready_message + " or opentelemetry_middleware_cls is empty"
 
     def is_ready(self) -> bool:
-        return bool(self.bootstrap_config.opentelemetry_middleware_cls and super().is_ready())
+        return super().is_ready() and bool(self.bootstrap_config.opentelemetry_middleware_cls)
 
     def bootstrap(self) -> None:
         if self.bootstrap_config.opentelemetry_middleware_cls and self.bootstrap_config.application.broker:
@@ -109,9 +114,18 @@ class FastStreamPrometheusInstrument(PrometheusInstrument):
     collector_registry: prometheus_client.CollectorRegistry = dataclasses.field(
         default_factory=prometheus_client.CollectorRegistry, init=False
     )
+    not_ready_message = (
+        PrometheusInstrument.not_ready_message
+        + " or prometheus_middleware_cls is missing or prometheus_client is not installed"
+    )
 
     def is_ready(self) -> bool:
-        return bool(self.bootstrap_config.prometheus_middleware_cls and super().is_ready())
+        return (
+            super().is_ready()
+            and import_checker.is_prometheus_client_installed
+            and bool(self.bootstrap_config.prometheus_middleware_cls)
+            and import_checker.is_prometheus_client_installed
+        )
 
     def bootstrap(self) -> None:
         self.bootstrap_config.application.mount(
@@ -124,6 +138,8 @@ def bootstrap(self) -> None:
 
 
 class FastStreamBootstrapper(BaseBootstrapper[AsgiFastStream]):
+    __slots__ = "bootstrap_config", "instruments"
+
     instruments_types: typing.ClassVar = [
         FastStreamOpenTelemetryInstrument,
         FastStreamSentryInstrument,
@@ -132,7 +148,10 @@ class FastStreamBootstrapper(BaseBootstrapper[AsgiFastStream]):
         FastStreamPrometheusInstrument,
     ]
     bootstrap_config: FastStreamConfig
-    __slots__ = "bootstrap_config", "instruments"
+    not_ready_message = "faststream is not installed"
+
+    def is_ready(self) -> bool:
+        return import_checker.is_faststream_installed
 
     def __init__(self, bootstrap_config: FastStreamConfig) -> None:
         super().__init__(bootstrap_config)

lite_bootstrap/bootstrappers/free_bootstrapper.py

@@ -12,13 +12,18 @@ class FreeBootstrapperConfig(LoggingConfig, OpentelemetryConfig, SentryConfig):
 
 
 class FreeBootstrapper(BaseBootstrapper[None]):
+    __slots__ = "bootstrap_config", "instruments"
+
     instruments_types: typing.ClassVar = [
         OpenTelemetryInstrument,
         SentryInstrument,
         LoggingInstrument,
     ]
     bootstrap_config: FreeBootstrapperConfig
-    __slots__ = "bootstrap_config", "instruments"
+    not_ready_message = ""
+
+    def is_ready(self) -> bool:
+        return True
 
     def __init__(self, bootstrap_config: FreeBootstrapperConfig) -> None:
         super().__init__(bootstrap_config)

lite_bootstrap/bootstrappers/litestar_bootstrapper.py

@@ -1,9 +1,7 @@
-import contextlib
 import dataclasses
 import typing
 
-from litestar.plugins.prometheus import PrometheusConfig, PrometheusController
-
+from lite_bootstrap import import_checker
 from lite_bootstrap.bootstrappers.base import BaseBootstrapper
 from lite_bootstrap.instruments.healthchecks_instrument import (
     HealthChecksConfig,
@@ -21,18 +19,21 @@
 from lite_bootstrap.instruments.sentry_instrument import SentryConfig, SentryInstrument
 
 
-with contextlib.suppress(ImportError):
+if import_checker.is_litestar_installed:
     import litestar
     from litestar.config.app import AppConfig
     from litestar.contrib.opentelemetry import OpenTelemetryConfig
+    from litestar.plugins.prometheus import PrometheusConfig, PrometheusController
+
+if import_checker.is_opentelemetry_installed:
     from opentelemetry.trace import get_tracer_provider
 
 
 @dataclasses.dataclass(kw_only=True, slots=True, frozen=True)
 class LitestarConfig(
     HealthChecksConfig, LoggingConfig, OpentelemetryConfig, PrometheusBootstrapperConfig, SentryConfig
 ):
-    application_config: AppConfig = dataclasses.field(default_factory=AppConfig)
+    application_config: "AppConfig" = dataclasses.field(default_factory=AppConfig)
     opentelemetry_excluded_urls: list[str] = dataclasses.field(default_factory=list)
     prometheus_additional_params: dict[str, typing.Any] = dataclasses.field(default_factory=dict)
 
@@ -41,7 +42,7 @@ class LitestarConfig(
 class LitestarHealthChecksInstrument(HealthChecksInstrument):
     bootstrap_config: LitestarConfig
 
-    def build_litestar_health_check_router(self) -> litestar.Router:
+    def build_litestar_health_check_router(self) -> "litestar.Router":
         @litestar.get(media_type=litestar.MediaType.JSON)
         async def health_check_handler() -> HealthCheckTypedDict:
             return self.render_health_check_data()
@@ -91,6 +92,10 @@ class LitestarSentryInstrument(SentryInstrument):
 @dataclasses.dataclass(kw_only=True, frozen=True)
 class LitestarPrometheusInstrument(PrometheusInstrument):
     bootstrap_config: LitestarConfig
+    not_ready_message = PrometheusInstrument.not_ready_message + " or prometheus_client is not installed"
+
+    def is_ready(self) -> bool:
+        return super().is_ready() and import_checker.is_prometheus_client_installed
 
     def bootstrap(self) -> None:
         class LitestarPrometheusController(PrometheusController):
@@ -108,6 +113,8 @@ class LitestarPrometheusController(PrometheusController):
 
 
 class LitestarBootstrapper(BaseBootstrapper[litestar.Litestar]):
+    __slots__ = "bootstrap_config", "instruments"
+
     instruments_types: typing.ClassVar = [
         LitestarOpenTelemetryInstrument,
         LitestarSentryInstrument,
@@ -116,7 +123,10 @@ class LitestarBootstrapper(BaseBootstrapper[litestar.Litestar]):
         LitestarPrometheusInstrument,
     ]
     bootstrap_config: LitestarConfig
-    __slots__ = "bootstrap_config", "instruments"
+    not_ready_message = "litestar is not installed"
+
+    def is_ready(self) -> bool:
+        return import_checker.is_litestar_installed
 
     def __init__(self, bootstrap_config: LitestarConfig) -> None:
         super().__init__(bootstrap_config)

lite_bootstrap/import_checker.py

@@ -0,0 +1,11 @@
+from importlib.util import find_spec
+
+
+is_opentelemetry_installed = find_spec("opentelemetry") is not None
+is_sentry_installed = find_spec("sentry_sdk") is not None
+is_structlog_installed = find_spec("structlog") is not None
+is_prometheus_client_installed = find_spec("prometheus_client") is not None
+is_fastapi_installed = find_spec("fastapi") is not None
+is_litestar_installed = find_spec("litestar") is not None
+is_faststream_installed = find_spec("faststream") is not None
+is_prometheus_fastapi_instrumentator_installed = find_spec("prometheus_fastapi_instrumentator") is not None

lite_bootstrap/instruments/base.py

@@ -14,6 +14,10 @@ class BaseConfig:
 class BaseInstrument(abc.ABC):
     bootstrap_config: BaseConfig
 
+    @property
+    @abc.abstractmethod
+    def not_ready_message(self) -> str: ...
+
     def bootstrap(self) -> None: ...  # noqa: B027
 
     def teardown(self) -> None: ...  # noqa: B027

lite_bootstrap/instruments/healthchecks_instrument.py

@@ -21,6 +21,7 @@ class HealthChecksConfig(BaseConfig):
 @dataclasses.dataclass(kw_only=True, slots=True, frozen=True)
 class HealthChecksInstrument(BaseInstrument):
     bootstrap_config: HealthChecksConfig
+    not_ready_message = "health_checks_enabled is False"
 
     def is_ready(self) -> bool:
         return self.bootstrap_config.health_checks_enabled