Flask Application Context

  current_app.name   → RuntimeError: Working outside of application context. This typically means that you attempted to use functionality that needed the current application. To solve this, set up an application context with app.app_context(). See the documentation for more information.
  g.x                → RuntimeError: Working outside of application context. This typically means that you attempted to use functionality that needed the current application. To solve this, set up an application context with app.app_context(). See the documentation for more information.
  url_for            → RuntimeError: Working outside of application context. This typically means that you attempted to use functionality that needed the current application. To solve this, set up an application context with app.app_context(). See the documentation for more information.
  has_app_context(): False | has_request_context(): False

  源码:
      1 | app = Flask("demo")
      2 | with app.app_context():
      3 |     print(current_app.name, has_app_context())
      4 |     print(current_app is app, current_app._get_current_object() is app, type(current_app).__name__)
      5 | print(has_app_context())
  demo True
  False True LocalProxy
  False

  g.hits=1 模块变量=1 g 的 id=19280
  g.hits=1 模块变量=2 g 的 id=20560
  g.hits=1 模块变量=3 g 的 id=19200

  appcontext_pushed → request_started → before_request → 视图函数 → after_request → request_finished → teardown_request(exc=None) → teardown_appcontext(exc=None) → appcontext_popped

  GET /boom → 500; ['teardown_appcontext 收到:ValueError']
  test_request_context 内:has_app_context = True , has_request_context = True , request.path = /x
  app_context 内:has_app_context = True , has_request_context = False
  在应用上下文里访问 request.path → Working outside of request context. This typically means that you attempted to use functionality that needed an active HTTP request. Consult the documentation on testing for information about how to a

   ['outer', 'inner', 'outer']

  flask --app cliapp hello → has_app_context=True current_app.name=cliapp
    test_cli_runner: has_app_context=True current_app.name=cliapp
    手动调用函数(没有 flask 命令): RuntimeError There is no active click context.