From 6fa366fbf2359ce6329a6390989f46c1a531338e Mon Sep 17 00:00:00 2001
From: Artur Shiriev <lesnik512@gmail.com>
Date: Thu, 17 Apr 2025 16:07:15 +0300
Subject: [PATCH] fix fastapi swagger

---
 .../bootstrappers/fastapi_bootstrapper.py           | 13 ++++++++++++-
 .../bootstrappers/litestar_bootstrapper.py          |  2 +-
 lite_bootstrap/instruments/swagger_instrument.py    |  3 +--
 tests/test_fastapi_bootstrap.py                     | 10 ++++++++++
 4 files changed, 24 insertions(+), 4 deletions(-)

diff --git a/lite_bootstrap/bootstrappers/fastapi_bootstrapper.py b/lite_bootstrap/bootstrappers/fastapi_bootstrapper.py
index d0d3083..8b897a3 100644
--- a/lite_bootstrap/bootstrappers/fastapi_bootstrapper.py
+++ b/lite_bootstrap/bootstrappers/fastapi_bootstrapper.py
@@ -1,6 +1,7 @@
 import contextlib
 import dataclasses
 import typing
+import warnings
 
 from lite_bootstrap import import_checker
 from lite_bootstrap.bootstrappers.base import BaseBootstrapper
@@ -35,12 +36,16 @@
 class FastAPIConfig(
     CorsConfig, HealthChecksConfig, LoggingConfig, OpentelemetryConfig, PrometheusConfig, SentryConfig, SwaggerConfig
 ):
-    application: "fastapi.FastAPI" = dataclasses.field(default_factory=lambda: fastapi.FastAPI())
+    application: "fastapi.FastAPI" = dataclasses.field(default=None)  # type: ignore[assignment]
     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)
     prometheus_expose_params: dict[str, typing.Any] = dataclasses.field(default_factory=dict)
 
+    def __post_init__(self) -> None:
+        if not self.application:
+            object.__setattr__(self, "application", fastapi.FastAPI(docs_url=self.swagger_path))
+
 
 @dataclasses.dataclass(kw_only=True, slots=True, frozen=True)
 class FastApiCorsInstrument(CorsInstrument):
@@ -139,6 +144,12 @@ class FastApiSwaggerInstrument(SwaggerInstrument):
     bootstrap_config: FastAPIConfig
 
     def bootstrap(self) -> None:
+        if self.bootstrap_config.swagger_path != self.bootstrap_config.application.docs_url:
+            warnings.warn(
+                f"swagger_path is differ from docs_url, "
+                f"{self.bootstrap_config.application.docs_url} will be used for docs path",
+                stacklevel=2,
+            )
         if self.bootstrap_config.swagger_offline_docs:
             enable_offline_docs(
                 self.bootstrap_config.application, static_path=self.bootstrap_config.swagger_static_path
diff --git a/lite_bootstrap/bootstrappers/litestar_bootstrapper.py b/lite_bootstrap/bootstrappers/litestar_bootstrapper.py
index 6d7bb4b..99bf29f 100644
--- a/lite_bootstrap/bootstrappers/litestar_bootstrapper.py
+++ b/lite_bootstrap/bootstrappers/litestar_bootstrapper.py
@@ -49,7 +49,7 @@ class LitestarConfig(
     application_config: "AppConfig" = dataclasses.field(default_factory=lambda: AppConfig())
     opentelemetry_excluded_urls: list[str] = dataclasses.field(default_factory=list)
     prometheus_additional_params: dict[str, typing.Any] = dataclasses.field(default_factory=dict)
-    swagger_path: str = "/docs"
+    swagger_extra_params: dict[str, typing.Any] = dataclasses.field(default_factory=dict)
 
 
 @dataclasses.dataclass(kw_only=True, slots=True, frozen=True)
diff --git a/lite_bootstrap/instruments/swagger_instrument.py b/lite_bootstrap/instruments/swagger_instrument.py
index ed415c7..68e54de 100644
--- a/lite_bootstrap/instruments/swagger_instrument.py
+++ b/lite_bootstrap/instruments/swagger_instrument.py
@@ -1,5 +1,4 @@
 import dataclasses
-import typing
 
 from lite_bootstrap.instruments.base import BaseConfig, BaseInstrument
 
@@ -7,8 +6,8 @@
 @dataclasses.dataclass(kw_only=True, frozen=True)
 class SwaggerConfig(BaseConfig):
     swagger_static_path: str = "/static"
+    swagger_path: str = "/docs"
     swagger_offline_docs: bool = False
-    swagger_extra_params: dict[str, typing.Any] = dataclasses.field(default_factory=dict)
 
 
 @dataclasses.dataclass(kw_only=True, slots=True, frozen=True)
diff --git a/tests/test_fastapi_bootstrap.py b/tests/test_fastapi_bootstrap.py
index d1a61f4..a3e8685 100644
--- a/tests/test_fastapi_bootstrap.py
+++ b/tests/test_fastapi_bootstrap.py
@@ -1,3 +1,6 @@
+import dataclasses
+
+import fastapi
 import pytest
 import structlog
 from opentelemetry.sdk.trace.export import ConsoleSpanExporter
@@ -61,6 +64,13 @@ def test_fastapi_bootstrapper_not_ready() -> None:
         FastAPIBootstrapper(bootstrap_config=FastAPIConfig())
 
 
+def test_fastapi_bootstrapper_docs_url_differ(fastapi_config: FastAPIConfig) -> None:
+    new_config = dataclasses.replace(fastapi_config, application=fastapi.FastAPI(docs_url="/custom-docs/"))
+    bootstrapper = FastAPIBootstrapper(bootstrap_config=new_config)
+    with pytest.warns(UserWarning, match="swagger_path is differ from docs_url"):
+        bootstrapper.bootstrap()
+
+
 @pytest.mark.parametrize(
     "package_name",
     [