使用Gunicorn部署项目时找不到flask_script模块，测试环境正常

看起来你碰到了部署时常见的环境不一致问题——测试环境跑的好好的，一用Gunicorn就找不到flask_script模块，我来帮你梳理几个大概率能解决的方向：

先把你的报错信息贴出来方便参考：

Traceback (most recent call last):
  File "/usr/lib/python2.7/site-packages/gunicorn/arbiter.py", line 583, in spawn_worker
    worker.init_process()
  File "/usr/lib/python2.7/site-packages/gunicorn/workers/base.py", line 129, in init_process
    self.load_wsgi()
  File "/usr/lib/python2.7/site-packages/gunicorn/workers/base.py", line 138, in load_wsgiapp
    self.wsgi = self.app.wsgi()
  File "/usr/lib/python2.7/site-packages/gunicorn/app/base.py", line 67, in wsgi
    self.callable = self.load()
  File "/usr/lib/python2.7/site-packages/gunicorn/app/wsgiapp.py", line 52, in load
    return self.load_wsgiapp()
  File "/usr/lib/python2.7/site-packages/gunicorn/app/wsgiapp.py", line 41, in load_wsgiapp
    return util.import_app(self.app_uri)
  File "/usr/lib/python2.7/site-packages/gunicorn/util.py", line 350, in import_app
    __import__(module)
  File "/home/iHome_Flask/ihome_pyhon02/manage.py", line 4, in <module>
    from flask_script import Manager
ImportError: No module named flask_script
[2018-05-23 09:15:46 +0000] [29933] [INFO] Worker exiting (pid: 29933)
[2018-05-23 09:15:46 +0000] [29928] [INFO] Shutting down: Master
[2018-05-23 09:15:46 +0000] [29928] [INFO] Reason: Worker failed to boot.
(flask_py2) [root@iZbp1bvf97jli08phztpplZ ihome_pyhon02]# vim manage.py

常见解决思路 #

1. 让Gunicorn使用你的虚拟环境 #

从报错路径能看出来，当前Gunicorn用的是系统自带的Python2.7，但你明明有flask_py2这个虚拟环境，这就是核心问题——环境不匹配。解决办法：

• 直接调用虚拟环境里的Gunicorn启动项目：

  /home/iHome_Flask/flask_py2/bin/gunicorn -w 4 manage:app
  

• 或者先激活虚拟环境再启动Gunicorn：

  source /home/iHome_Flask/flask_py2/bin/activate
  gunicorn -w 4 manage:app
  

2. 检查虚拟环境的依赖完整性 #

有可能你的虚拟环境里压根没装flask_script，或者依赖有缺失。激活虚拟环境后重新安装：

source /home/iHome_Flask/flask_py2/bin/activate
pip install flask-script
# 如果有requirements.txt文件，更稳妥的方式是一次性安装所有依赖
pip install -r requirements.txt

3. 确保在项目根目录启动Gunicorn #

如果启动Gunicorn时不在项目根目录，可能会导致Python找不到模块路径。先切换到项目目录再操作：

cd /home/iHome_Flask/ihome_pyhon02/
source ../flask_py2/bin/activate
gunicorn manage:app

一般来说，前两个方法就能解决你的问题，优先试试用虚拟环境的Gunicorn启动，应该就能找到flask_script模块了。

内容的提问来源于stack exchange，提问作者1am9a09e