python - Jinja2 For 循环导致 Google App Engine 崩溃

标签 python google-app-engine jinja2

我有一个简单的 Jinja 模板测试片段，我正在为 HTML 模板编写，但由于某些原因循环导致在线应用程序引擎和 devappserver 崩溃。我尝试用常量替换 for 循环的主题，只是为了测试实际循环，并且根据 Cloud SDK Shell 错误消息，我已将其与 for 循环的实际语法隔离。该片段有什么问题？

错误:

  File "C:\Users\Skyler\Documents\Reverie\reflect\templates\index.html", 
line 9,
 in template
    {{% for test in my_list %}}
TemplateSyntaxError: unexpected '%'

index.html

<!DOCTYPE html>
<html>
<head>
    <title>{{title}}</title>
</head>
<body>
<h1> {{my_list[3]}} </h1>
<ul>
    {{% for test in my_list %}}
    <li>{{my_list[1]}}</li>
    {{% endfor %}}
</ul>
</body>
</html>

测试.py

import webapp2
import jinja2
import os

template_dir = os.path.join(os.path.dirname(__file__), "templates")
jinja_env = jinja2.Environment(loader = jinja2.FileSystemLoader(template_dir), autoescape = True)

class Handler(webapp2.RequestHandler):
    def write(self, *a, **kw):
        self.response.write(*a, **kw)

    def render_str(self, template, **params):
        t = jinja_env.get_template(template)
        return t.render(params)

    def render(self, template, **kw):
        self.write(self.render_str(template, **kw))

class MainPage(Handler):
    """docstring for MainPage"""
    def get(self):
        self.render("index.html", title="Nani", my_list=[0,1,2,"string"])

app = webapp2.WSGIApplication([('/', MainPage),], debug=True)

app.yaml

runtime: python27
api_version: 1
threadsafe: true

handlers:
- url: /
  script: test.app

libraries:
- name: jinja2
  version: latest

完整的堆栈跟踪

ERROR    2017-07-18 05:02:36,960 webapp2.py:1528] unexpected '%'
Traceback (most recent call last):
  File "C:\Users\Skyler\AppData\Local\Google\Cloud SDK\google-cloud-sdk\platform
\google_appengine\lib\webapp2-2.3\webapp2.py", line 1511, in __call__
    rv = self.handle_exception(request, response, e)
  File "C:\Users\Skyler\AppData\Local\Google\Cloud SDK\google-cloud-sdk\platform
\google_appengine\lib\webapp2-2.3\webapp2.py", line 1505, in __call__
    rv = self.router.dispatch(request, response)
  File "C:\Users\Skyler\AppData\Local\Google\Cloud SDK\google-cloud-sdk\platform
\google_appengine\lib\webapp2-2.3\webapp2.py", line 1253, in default_dispatcher
    return route.handler_adapter(request, response)
  File "C:\Users\Skyler\AppData\Local\Google\Cloud SDK\google-cloud-sdk\platform
\google_appengine\lib\webapp2-2.3\webapp2.py", line 1077, in __call__
    return handler.dispatch()
  File "C:\Users\Skyler\AppData\Local\Google\Cloud SDK\google-cloud-sdk\platform
\google_appengine\lib\webapp2-2.3\webapp2.py", line 547, in dispatch
    return self.handle_exception(e, self.app.debug)
  File "C:\Users\Skyler\AppData\Local\Google\Cloud SDK\google-cloud-sdk\platform
\google_appengine\lib\webapp2-2.3\webapp2.py", line 545, in dispatch
    return method(*args, **kwargs)
  File "C:\Users\Skyler\Documents\Reverie\reflect\test.py", line 22, in get
    self.render("index.html", title="Nani", my_list=[0,1,2,"string"])
  File "C:\Users\Skyler\Documents\Reverie\reflect\test.py", line 17, in render
    self.write(self.render_str(template, **kw))
  File "C:\Users\Skyler\Documents\Reverie\reflect\test.py", line 13, in render_s
tr
    t = jinja_env.get_template(template)
  File "C:\Users\Skyler\AppData\Local\Google\Cloud SDK\google-cloud-sdk\platform
\google_appengine\lib\jinja2-2.6\jinja2\environment.py", line 719, in get_templa
te
    return self._load_template(name, self.make_globals(globals))
  File "C:\Users\Skyler\AppData\Local\Google\Cloud SDK\google-cloud-sdk\platform
\google_appengine\lib\jinja2-2.6\jinja2\environment.py", line 693, in _load_temp
late
    template = self.loader.load(self, name, globals)
  File "C:\Users\Skyler\AppData\Local\Google\Cloud SDK\google-cloud-sdk\platform
\google_appengine\lib\jinja2-2.6\jinja2\loaders.py", line 127, in load
    code = environment.compile(source, name, filename)
  File "C:\Users\Skyler\AppData\Local\Google\Cloud SDK\google-cloud-sdk\platform
\google_appengine\lib\jinja2-2.6\jinja2\environment.py", line 493, in compile
    self.handle_exception(exc_info, source_hint=source)
  File "C:\Users\Skyler\Documents\Reverie\reflect\templates\index.html", line 9,
 in template
    {{% for test in my_list %}}
TemplateSyntaxError: unexpected '%'
ERROR    2017-07-18 05:02:36,960 wsgi.py:279]
Traceback (most recent call last):
  File "C:\Users\Skyler\AppData\Local\Google\Cloud SDK\google-cloud-sdk\platform
\google_appengine\google\appengine\runtime\wsgi.py", line 267, in Handle
    result = handler(dict(self._environ), self._StartResponse)
  File "C:\Users\Skyler\AppData\Local\Google\Cloud SDK\google-cloud-sdk\platform
\google_appengine\lib\webapp2-2.3\webapp2.py", line 1519, in __call__
    response = self._internal_error(e)
  File "C:\Users\Skyler\AppData\Local\Google\Cloud SDK\google-cloud-sdk\platform
\google_appengine\lib\webapp2-2.3\webapp2.py", line 1511, in __call__
    rv = self.handle_exception(request, response, e)
  File "C:\Users\Skyler\AppData\Local\Google\Cloud SDK\google-cloud-sdk\platform
\google_appengine\lib\webapp2-2.3\webapp2.py", line 1505, in __call__
    rv = self.router.dispatch(request, response)
  File "C:\Users\Skyler\AppData\Local\Google\Cloud SDK\google-cloud-sdk\platform
\google_appengine\lib\webapp2-2.3\webapp2.py", line 1253, in default_dispatcher
    return route.handler_adapter(request, response)
  File "C:\Users\Skyler\AppData\Local\Google\Cloud SDK\google-cloud-sdk\platform
\google_appengine\lib\webapp2-2.3\webapp2.py", line 1077, in __call__
    return handler.dispatch()
  File "C:\Users\Skyler\AppData\Local\Google\Cloud SDK\google-cloud-sdk\platform
\google_appengine\lib\webapp2-2.3\webapp2.py", line 547, in dispatch
    return self.handle_exception(e, self.app.debug)
  File "C:\Users\Skyler\AppData\Local\Google\Cloud SDK\google-cloud-sdk\platform
\google_appengine\lib\webapp2-2.3\webapp2.py", line 545, in dispatch
    return method(*args, **kwargs)
  File "C:\Users\Skyler\Documents\Reverie\reflect\test.py", line 22, in get
    self.render("index.html", title="Nani", my_list=[0,1,2,"string"])
  File "C:\Users\Skyler\Documents\Reverie\reflect\test.py", line 17, in render
    self.write(self.render_str(template, **kw))
  File "C:\Users\Skyler\Documents\Reverie\reflect\test.py", line 13, in render_s
tr
    t = jinja_env.get_template(template)
  File "C:\Users\Skyler\AppData\Local\Google\Cloud SDK\google-cloud-sdk\platform
\google_appengine\lib\jinja2-2.6\jinja2\environment.py", line 719, in get_templa
te
    return self._load_template(name, self.make_globals(globals))
  File "C:\Users\Skyler\AppData\Local\Google\Cloud SDK\google-cloud-sdk\platform
\google_appengine\lib\jinja2-2.6\jinja2\environment.py", line 693, in _load_temp
late
    template = self.loader.load(self, name, globals)
  File "C:\Users\Skyler\AppData\Local\Google\Cloud SDK\google-cloud-sdk\platform
\google_appengine\lib\jinja2-2.6\jinja2\loaders.py", line 127, in load
    code = environment.compile(source, name, filename)
  File "C:\Users\Skyler\AppData\Local\Google\Cloud SDK\google-cloud-sdk\platform
\google_appengine\lib\jinja2-2.6\jinja2\environment.py", line 493, in compile
    self.handle_exception(exc_info, source_hint=source)
  File "C:\Users\Skyler\Documents\Reverie\reflect\templates\index.html", line 9,
 in template
    {{% for test in my_list %}}
TemplateSyntaxError: unexpected '%'
INFO     2017-07-17 22:02:36,970 module.py:832] default: "GET / HTTP/1.1" 500 -

最佳答案

这可能是因为您似乎过多地使用了一个大括号。查看 docs 中的 for 循环:

<title>{% block title %}{% endblock %}</title> <ul> {% for user in users %} <li><a href="{{ user.url }}">{{ user.username }}</a></li> {% endfor %} </ul>

语句 {% for user in users %} 中只有一个花括号而您的语句使用两个花括号: {{% for test in my_list %}} 。

尝试改为:{% for test in my_list %}看看会发生什么。

关于python - Jinja2 For 循环导致 Google App Engine 崩溃，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/45157745/

上一篇：python - tensorflow 中逻辑回归模型的系数

下一篇：python - # 符号截断 URL 文本 Flask 应用程序

相关文章：

python - 如何登录 Appengine 中的任意用户以使用 Drive SDK？

python - 使用 Flask 和 WTForms 从数据库查询动态单选按钮

ansible - 在 Ansible 中使用模板模块附加文件

python - 为什么验证不适用于表单请求？

python - 从首字母为小写的数据框中删除行

python - 求解大数的线性方程

python - Google App Engine 和 Google Apps Marketplace

python - 谷歌云端点 : migrating v1 to v2 getting error in discovery call

python - 为什么我会收到此 Django TypeError？

java - Spring Security - 持久记住我的问题

©2024 IT工具网  联系我们