Flask ImportError：无法在heroku上导入名称'app'

【问题标题】：Flask ImportError: cannot import name 'app' on herokuFlask ImportError：无法在heroku上导入名称'app'
【发布时间】：2021-06-28 23:06:00
【问题描述】：

我创建了一个部署在 Heroku 上的 flask+react 应用程序，在我尝试添加数据库并尝试解决循环导入问题之前，它一切正常。现在，我的结构如下：

api/__init__.py

from flask import Flask
from flask_sqlalchemy import SQLAlchemy
from flask_migrate import Migrate
from api.config import Config

app = Flask(__name__, static_folder="../build", static_url_path="/")
app.config.from_object(Config)
db = SQLAlchemy(app)
migrate = Migrate(app, db)

import api.models

Procfile

web: flask db upgrade; gunicorn --pythonpath api api:app

还有我的主文件api/api.py

from flask import Flask
from api import app, db
from api.models import Scab

@app.route('/api/home')
def home():
   pass

# More routes

这是我的api/.flaskenv 文件

FLASK_APP=api.py
FLASK_ENV=development

这一切在本地都可以正常工作，但是当我在 Heroku 上部署它时，我得到 ImportError 和另一个错误：没有这样的命令 'db'。以下是日志：

2021-04-02T00:20:18.544760+00:00 app[web.1]: Error: No such command 'db'.
2021-04-02T00:20:19.505547+00:00 app[web.1]: [2021-04-02 00:20:19 +0000] [9] [INFO] Starting gunicorn 20.0.4
2021-04-02T00:20:19.506386+00:00 app[web.1]: [2021-04-02 00:20:19 +0000] [9] [INFO] Listening at: http://0.0.0.0:10654 (9)
2021-04-02T00:20:19.506514+00:00 app[web.1]: [2021-04-02 00:20:19 +0000] [9] [INFO] Using worker: sync
2021-04-02T00:20:19.586590+00:00 app[web.1]: [2021-04-02 00:20:19 +0000] [12] [INFO] Booting worker with pid: 12
2021-04-02T00:20:19.614419+00:00 app[web.1]: [2021-04-02 00:20:19 +0000] [13] [INFO] Booting worker with pid: 13
2021-04-02T00:20:19.690243+00:00 heroku[web.1]: State changed from starting to up
2021-04-02T00:20:20.419746+00:00 app[web.1]: [2021-04-02 00:20:20 +0000] [13] [ERROR] Exception in worker process
2021-04-02T00:20:20.419759+00:00 app[web.1]: Traceback (most recent call last):
2021-04-02T00:20:20.419760+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/gunicorn/arbiter.py", line 583, in spawn_worker
2021-04-02T00:20:20.419761+00:00 app[web.1]: worker.init_process()
2021-04-02T00:20:20.419762+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/gunicorn/workers/base.py", line 119, in init_process
2021-04-02T00:20:20.419762+00:00 app[web.1]: self.load_wsgi()
2021-04-02T00:20:20.419762+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/gunicorn/workers/base.py", line 144, in load_wsgi
2021-04-02T00:20:20.419763+00:00 app[web.1]: self.wsgi = self.app.wsgi()
2021-04-02T00:20:20.419764+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/gunicorn/app/base.py", line 67, in wsgi
2021-04-02T00:20:20.419764+00:00 app[web.1]: self.callable = self.load()
2021-04-02T00:20:20.419765+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/gunicorn/app/wsgiapp.py", line 49, in load
2021-04-02T00:20:20.419765+00:00 app[web.1]: return self.load_wsgiapp()
2021-04-02T00:20:20.419766+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/gunicorn/app/wsgiapp.py", line 39, in load_wsgiapp
2021-04-02T00:20:20.419766+00:00 app[web.1]: return util.import_app(self.app_uri)
2021-04-02T00:20:20.419767+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/gunicorn/util.py", line 358, in import_app
2021-04-02T00:20:20.419767+00:00 app[web.1]: mod = importlib.import_module(module)
2021-04-02T00:20:20.419767+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/importlib/__init__.py", line 126, in import_module
2021-04-02T00:20:20.419769+00:00 app[web.1]: return _bootstrap._gcd_import(name[level:], package, level)
2021-04-02T00:20:20.419769+00:00 app[web.1]: File "<frozen importlib._bootstrap>", line 994, in _gcd_import
2021-04-02T00:20:20.419769+00:00 app[web.1]: File "<frozen importlib._bootstrap>", line 971, in _find_and_load
2021-04-02T00:20:20.419770+00:00 app[web.1]: File "<frozen importlib._bootstrap>", line 955, in _find_and_load_unlocked
2021-04-02T00:20:20.419770+00:00 app[web.1]: File "<frozen importlib._bootstrap>", line 665, in _load_unlocked
2021-04-02T00:20:20.419771+00:00 app[web.1]: File "<frozen importlib._bootstrap_external>", line 678, in exec_module
2021-04-02T00:20:20.419771+00:00 app[web.1]: File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
2021-04-02T00:20:20.419772+00:00 app[web.1]: File "/app/api/api.py", line 3, in <module>
2021-04-02T00:20:20.419772+00:00 app[web.1]: from api import app, db
2021-04-02T00:20:20.421118+00:00 app[web.1]: ImportError: cannot import name 'app'
2021-04-02T00:20:20.423394+00:00 app[web.1]: [2021-04-02 00:20:20 +0000] [13] [INFO] Worker exiting (pid: 13)
2021-04-02T00:20:20.626024+00:00 app[web.1]: [2021-04-02 00:20:20 +0000] [12] [ERROR] Exception in worker process
2021-04-02T00:20:20.626026+00:00 app[web.1]: Traceback (most recent call last):
2021-04-02T00:20:20.626027+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/gunicorn/arbiter.py", line 583, in spawn_worker
2021-04-02T00:20:20.626028+00:00 app[web.1]: worker.init_process()
2021-04-02T00:20:20.626028+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/gunicorn/workers/base.py", line 119, in init_process
2021-04-02T00:20:20.626029+00:00 app[web.1]: self.load_wsgi()
2021-04-02T00:20:20.626029+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/gunicorn/workers/base.py", line 144, in load_wsgi
2021-04-02T00:20:20.626029+00:00 app[web.1]: self.wsgi = self.app.wsgi()
2021-04-02T00:20:20.626030+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/gunicorn/app/base.py", line 67, in wsgi
2021-04-02T00:20:20.626030+00:00 app[web.1]: self.callable = self.load()
2021-04-02T00:20:20.626036+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/gunicorn/app/wsgiapp.py", line 49, in load
2021-04-02T00:20:20.626036+00:00 app[web.1]: return self.load_wsgiapp()
2021-04-02T00:20:20.626036+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/gunicorn/app/wsgiapp.py", line 39, in load_wsgiapp
2021-04-02T00:20:20.626037+00:00 app[web.1]: return util.import_app(self.app_uri)
2021-04-02T00:20:20.626037+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/gunicorn/util.py", line 358, in import_app
2021-04-02T00:20:20.626038+00:00 app[web.1]: mod = importlib.import_module(module)
2021-04-02T00:20:20.626038+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/importlib/__init__.py", line 126, in import_module
2021-04-02T00:20:20.626038+00:00 app[web.1]: return _bootstrap._gcd_import(name[level:], package, level)
2021-04-02T00:20:20.626039+00:00 app[web.1]: File "<frozen importlib._bootstrap>", line 994, in _gcd_import
2021-04-02T00:20:20.626039+00:00 app[web.1]: File "<frozen importlib._bootstrap>", line 971, in _find_and_load
2021-04-02T00:20:20.626040+00:00 app[web.1]: File "<frozen importlib._bootstrap>", line 955, in _find_and_load_unlocked
2021-04-02T00:20:20.626040+00:00 app[web.1]: File "<frozen importlib._bootstrap>", line 665, in _load_unlocked
2021-04-02T00:20:20.626041+00:00 app[web.1]: File "<frozen importlib._bootstrap_external>", line 678, in exec_module
2021-04-02T00:20:20.626041+00:00 app[web.1]: File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
2021-04-02T00:20:20.626041+00:00 app[web.1]: File "/app/api/api.py", line 3, in <module>
2021-04-02T00:20:20.626042+00:00 app[web.1]: from api import app, db
2021-04-02T00:20:20.630514+00:00 app[web.1]: ImportError: cannot import name 'app'
2021-04-02T00:20:20.631639+00:00 app[web.1]: [2021-04-02 00:20:20 +0000] [12] [INFO] Worker exiting (pid: 12)
2021-04-02T00:20:20.753083+00:00 app[web.1]: Traceback (most recent call last):
2021-04-02T00:20:20.753644+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/gunicorn/arbiter.py", line 209, in run
2021-04-02T00:20:20.754182+00:00 app[web.1]: self.sleep()
2021-04-02T00:20:20.754224+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/gunicorn/arbiter.py", line 357, in sleep
2021-04-02T00:20:20.754611+00:00 app[web.1]: ready = select.select([self.PIPE[0]], [], [], 1.0)
2021-04-02T00:20:20.754651+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/gunicorn/arbiter.py", line 242, in handle_chld
2021-04-02T00:20:20.754958+00:00 app[web.1]: self.reap_workers()
2021-04-02T00:20:20.755004+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/gunicorn/arbiter.py", line 525, in reap_workers
2021-04-02T00:20:20.755439+00:00 app[web.1]: raise HaltServer(reason, self.WORKER_BOOT_ERROR)
2021-04-02T00:20:20.761100+00:00 app[web.1]: gunicorn.errors.HaltServer: <HaltServer 'Worker failed to boot.' 3>
2021-04-02T00:20:20.761142+00:00 app[web.1]:
2021-04-02T00:20:20.761143+00:00 app[web.1]: During handling of the above exception, another exception occurred:
2021-04-02T00:20:20.761143+00:00 app[web.1]:
2021-04-02T00:20:20.761184+00:00 app[web.1]: Traceback (most recent call last):
2021-04-02T00:20:20.761230+00:00 app[web.1]: File "/app/.heroku/python/bin/gunicorn", line 8, in <module>
2021-04-02T00:20:20.761539+00:00 app[web.1]: sys.exit(run())
2021-04-02T00:20:20.761582+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/gunicorn/app/wsgiapp.py", line 58, in run
2021-04-02T00:20:20.761804+00:00 app[web.1]: WSGIApplication("%(prog)s [OPTIONS] [APP_MODULE]").run()
2021-04-02T00:20:20.761843+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/gunicorn/app/base.py", line 228, in run
2021-04-02T00:20:20.762169+00:00 app[web.1]: super().run()
2021-04-02T00:20:20.762206+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/gunicorn/app/base.py", line 72, in run
2021-04-02T00:20:20.762433+00:00 app[web.1]: Arbiter(self).run()
2021-04-02T00:20:20.762513+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/gunicorn/arbiter.py", line 229, in run
2021-04-02T00:20:20.762748+00:00 app[web.1]: self.halt(reason=inst.reason, exit_status=inst.exit_status)
2021-04-02T00:20:20.762774+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/gunicorn/arbiter.py", line 342, in halt
2021-04-02T00:20:20.763096+00:00 app[web.1]: self.stop()
2021-04-02T00:20:20.763137+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/gunicorn/arbiter.py", line 393, in stop
2021-04-02T00:20:20.763542+00:00 app[web.1]: time.sleep(0.1)
2021-04-02T00:20:20.763584+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/gunicorn/arbiter.py", line 242, in handle_chld
2021-04-02T00:20:20.763840+00:00 app[web.1]: self.reap_workers()
2021-04-02T00:20:20.763866+00:00 app[web.1]: File "/app/.heroku/python/lib/python3.6/site-packages/gunicorn/arbiter.py", line 525, in reap_workers
2021-04-02T00:20:20.764203+00:00 app[web.1]: raise HaltServer(reason, self.WORKER_BOOT_ERROR)
2021-04-02T00:20:20.764246+00:00 app[web.1]: gunicorn.errors.HaltServer: <HaltServer 'Worker failed to boot.' 3>
2021-04-02T00:20:20.900697+00:00 heroku[web.1]: Process exited with status 1
2021-04-02T00:20:20.968554+00:00 heroku[web.1]: State changed from up to crashed
2021-04-02T00:20:21.743210+00:00 heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/" host=orchardwatch.herokuapp.com request_id=3efcde74-5cf4-4496-a6ec-755f42350faf fwd="24.62.206.244" dyno= connect= service= status=503 bytes= protocol=https
2021-04-02T00:20:27.035992+00:00 heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/favicon.ico" host=orchardwatch.herokuapp.com request_id=9dc2e0e3-8a3a-4b07-92ee-b81e9e6fc9ec fwd="24.62.206.244" dyno=web.1 connect=5001ms service= status=503 bytes= protocol=https
2021-04-02T00:33:16.208921+00:00 heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/" host=orchardwatch.herokuapp.com request_id=7c68f45f-e287-4395-a7d2-75eec7177f9f fwd="54.162.81.130" dyno= connect= service= status=503 bytes= protocol=http

【问题讨论】：

    标签： python flask heroku


    【解决方案1】： 
    from location import routes_file

    这在你的 init.py 文件的底部

    用正确的名称替换伪名称

    编辑 1：

    在您的 .flaskenv 文件中，将 FLASK_APP 变量设置为您的 init 文件 例如，我在 heroku 上的烧瓶应用程序在我的 .flaskenv 文件中有以下内容。

    FLASK_APP=__init__.py

    【讨论】：

      【解决方案2】：

      您可能只想要：而不是from api import app, db：

      import app

      默认情况下，这也会在导入范围内公开该模块（app、db）中的变量。

      【讨论】：

      • 我试过了，它给了我本地应用程序的 ModuleNotFound。有什么想法吗？
      猜你喜欢
      • 1970-01-01
      • 2019-06-03
      • 2018-08-10
      • 2014-09-21
      • 1970-01-01
      • 2019-05-01
      • 2018-08-25
      • 1970-01-01
      • 2022-01-12
      相关资源
      最近更新 更多
      热门标签
      Java Python linux javascript Mysql C# Docker 算法 前端 SpringBoot Redis Vue spring 设计模式 .net core .net kubernetes c++ 数据库 数据结构 大数据 js 机器学习 微服务 Android Go 程序员 面试 JVM ASP.net core 云原生 人工智能 后端 PHP git CSS golang k8s Nginx Django mybatis 深度学习 多线程 React 架构 devops 爬虫 云计算 Spring Boot LeetCode