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笔记52笨办法学python练习51继续建立与浏览器的关系，笔记之三

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一、重走一趟练习50的路程

1、在1pthw后建立flask目录 2、cd projects 3、mkdir gothonweb 4、cd gothonweb 5、mkdir bin gothonweb tests docs templates 6、touch gothonweb/init.py 7、touch tests/init.py 8、在templates下运行app.py 9、终端显示

在这里插入代码片PS C:\Users\lenovo\.venvs\1pthw\flask\projects\gothonweb\templates> py app.py * Serving Flask app "app" (lazy loading) * Environment: production   WARNING: This is a development server. Do not use it in a production deployment.   Use a production WSGI server instead. * Debug mode: off * Running on http://127.0.0.1:5000/ (Press CTRL+C to quit)127.0.0.1 - - [08/Aug/2020 14:54:09] "[37mGET / HTTP/1.1[0m" 200 -127.0.0.1 - - [08/Aug/2020 14:54:09] "[33mGET /favicon.ico HTTP/1.1[0m" 404 -127.0.0.1 - - [08/Aug/2020 14:59:37] "[37mGET / HTTP/1.1[0m" 200 -127.0.0.1 - - [08/Aug/2020 14:59:43] "[37mGET / HTTP/1.1[0m" 200 -PS C:\Users\lenovo\.venvs\1pthw\flask\projects\gothonweb\templates> py app.py  File "app.py", line 6    greeting =

10、浏览器显示greeting

11、去掉app.py中的第六行，重启 12、浏览器显示 Internal Server Error 13、终端显示 PS C:\Users\lenovo.venvs\1pthw\flask\projects\gothonweb\templates> py app.py

• Serving Flask app “app” (lazy loading)
• Environment: production
  WARNING: This is a development server. Do not use it in a production deployment.
  Use a production WSGI server instead.
• Debug mode: off
• Running on http://127.0.0.1:5000/ (Press CTRL+C to quit)
  [2020-08-08 15:04:23,004] ERROR in app: Exception on / [GET]
  Traceback (most recent call last):
  File “C:\Users\lenovo\AppData\Local\Programs\Python\Python38\lib\site-packages\flask\app.py”, line 2447, in wsgi_app
  response = self.full_dispatch_request()
  File “C:\Users\lenovo\AppData\Local\Programs\Python\Python38\lib\site-packages\flask\app.py”, line 1952, in full_dispatch_request
  rv = self.handle_user_exception(e)
  File “C:\Users\lenovo\AppData\Local\Programs\Python\Python38\lib\site-packages\flask\app.py”, line 1821, in handle_user_exception
  reraise(exc_type, exc_value, tb)
  File “C:\Users\lenovo\AppData\Local\Programs\Python\Python38\lib\site-packages\flask_compat.py”, line 39, in reraise
  raise value
  File “C:\Users\lenovo\AppData\Local\Programs\Python\Python38\lib\site-packages\flask\app.py”, line 1950, in full_dispatch_request
  rv = self.dispatch_request()
  File “C:\Users\lenovo\AppData\Local\Programs\Python\Python38\lib\site-packages\flask\app.py”, line 1936, in dispatch_request
  return self.view_functions
  File “app.py”, line 6, in hello_world
  greeting
  NameError: name ‘greeting’ is not defined
  127.0.0.1 - - [08/Aug/2020 15:04:23] “[35m[1mGET / HTTP/1.1[0m” 500 -

14、创建index.html文件和修改app、.py

浏览器上出现绿色greeting文字 {% if greeting %} I just wanted to say { { greeting }}. {% else %} Hello, world! {& endif %}

15、但每次执行app.py的结果都是internal server error

没有办法，前进到练习51

二、再读而且续练那个练习51

1、web工作原理，略去 2、将练习50的app.py改成form_test.py 3、在ps中执行form_test.py 目录templates下执行不动 4、在另一个目录tests下执行 依然执行不动 5、再换一个目录，退到哪一个都不行 6、按动ctrl C启动访问网页，启动不成功 几乎每次都出现拒绝访问，截图

7、建立表单hello_form.html

8、将练习50的app.py改为练习51的app.py 9、在目录templates下执行app 又是internal server error

10、将练习50中的index.html修改成index_laid_out.html

11、把hello_form.html修改成hello_form_laid_out.html 12、创建一个处于templates中的新文件layout.html 13、在tests中创建一个测试文件app_test.py 14、用nosetests通过 执行代码

在这里插入代码片PS C:\Users\lenovo\.venvs\1pthw\flask\projects\gothonweb\templates> cd..PS C:\Users\lenovo\.venvs\1pthw\flask\projects\gothonweb> cd testsPS C:\Users\lenovo\.venvs\1pthw\flask\projects\gothonweb\tests> py app_tests.pyTraceback (most recent call last):  File "app_tests.py", line 2, in 
   
        from app import appModuleNotFoundError: No module named 'app'PS C:\Users\lenovo\.venvs\1pthw\flask\projects\gothonweb\tests> nosetests----------------------------------------------------------------------Ran 0 tests in 0.000sOK
   

15、但在py中没有这个模块，搞不懂

在这里插入代码片PS C:\Users\lenovo\.venvs\1pthw\flask\projects\gothonweb> cd testsPS C:\Users\lenovo\.venvs\1pthw\flask\projects\gothonweb\tests> py app_tests.pyTraceback (most recent call last):  File "app_tests.py", line 2, in 
   
        from app import appModuleNotFoundError: No module named 'app'
   

16、在templates目录下试试

在这里插入代码片PS C:\Users\lenovo.venvs\1pthw\flask\projects\gothonweb> cd templates

PS C:\Users\lenovo.venvs\1pthw\flask\projects\gothonweb\templates> py app_tests.py C:\Users\lenovo\AppData\Local\Programs\Python\Python38\python.exe: can’t open file ‘app_tests.py’: [Errno 2] No such file or directory PS C:\Users\lenovo.venvs\1pthw\flask\projects\gothonweb\templates>

17、我按照教材的要求安装了Apache服务器，但这个服务器的作用还体会不到。

可能失败了，但失败了也没有什么关系，继续前行到练习52. 我安装的Abache服务器 这个练习51折腾的时间够长的了，感概多多，暂且搁置吧。练习52开始。

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