FastAPI多API端点路径参数匹配异常，非对应方法被执行求助

问题原因 #

FastAPI的路由匹配是按代码定义的顺序进行前缀匹配的。你的第一个路由/project/{project_id}/{employee_id}是动态参数路由，会匹配所有符合/project/xxx/xxx格式的请求——当你访问/project/details/123或/project/metadata/456时，FastAPI会把details/metadata当成project_id的参数值，把后面的ID当成employee_id，直接触发method_one，完全不会走到后面的端点2和3。

另外注意：你原来的method_one函数参数里写了organization_id: str，但路由路径里是{employee_id}，这会导致参数不匹配报错，也需要同步修正。

修复方案 #

调整路由的定义顺序，把带有静态前缀的路由（/project/details/、/project/metadata/）放在动态参数路由的前面，让FastAPI先匹配精确的静态路径，再匹配动态参数路径。

修复后的代码：

# GET API Endpoint 2
@router.get("/project/details/{project_id}")
async def method_two(
    project_id: str, session: AsyncSession = Depends(get_db)
):
    try:
        return await CustomController.method_two(
            session=session, project_id=project_id
        )
    except Exception as e:
        return custom_exception_handler(e)

# GET API Endpoint 3
@router.get("/project/metadata/{project_id}")
async def method_three(
    project_id: str, session: AsyncSession = Depends(get_db)
):
    try:
        return await CustomController.method_three(
            session=session, project_id=project_id
        )
    except Exception as e:
        return custom_exception_handler(e)

# GET API Endpoint 1
@router.get("/project/{project_id}/{employee_id}")
async def method_one(
    project_id: str, employee_id: str, session: AsyncSession = Depends(get_db)
):
    try:
        return await CustomController.method_one(
            session, project_id, employee_id
        )
    except Exception as e:
        return custom_exception_handler(e)

内容的提问来源于stack exchange，提问作者Pranav N