title: csrf_tokens do not match in flask & nginx
body: <p>Now I am trying to develop server using nginx + unicorn + flask.</p>
  
  <p>If I execute python only, csrf_tokens work without any problems.</p>
  
  <p>However, if I execute python using nginx + unicorn + flask, the error occurs.</p>
  
  <p><strong>400 BAD Request - The CSRF session token is missing. or The CSRF tokens do not match.</strong></p>
  
  <p>Is there additional settings that I should have done for nginx for session? </p>
  
  <p>or Did I miss something??</p>
  
  <p>app/<strong>init</strong>.py</p>
  
  <pre><code>from flask_wtf.csrf import CsrfProtect
  
  csrf = CsrfProtect()
  
  def create_app(config_name):
     app = Flask(__name__, instance_path='/instance')
     app.config.from_object(config[config_name])
     config[config_name].init_app(app)
  
     bootstrap.init_app(app)
     moment.init_app(app)
     csrf.init_app(app)
     app.config.update(CSRF_ENABLED = app.config['CSRF_ENABLED'])
  
     //CSRF_ENABLED = True
  
     return app
  </code></pre>
  
  <p>login.html</p>
  
  <pre><code>&lt;form action="{{url_for('.login')}}" class="form-signin text-center" method="POST"&gt;
      {{ form.csrf_token }}
  &lt;/form&gt;
  </code></pre>