我在使用Genshi py:for
属性时遇到问题。我做错了什么?代码写在下面;要运行,使用Python 2创建virtualenv,执行pip install genshi flask
,复制隔离目录中列出的文件,然后运行python hello.py
hello.py
的内容:
import os.path
import traceback
import flask
import genshi.template
app = flask.Flask(__name__)
template_dir = os.path.join(os.path.dirname(__file__), 'templates')
loader = genshi.template.TemplateLoader(template_dir, auto_reload=True)
MESSAGES = [
"Hello",
"World",
"Sup?",
]
@app.route("/", defaults={"name": ""})
@app.route("/<path:name>")
def show(name):
template_name = name + ".html"
try:
template = loader.load(template_name)
stream = template.generate(
messages=MESSAGES,
)
rendered = stream.render('html', doctype='html')
except Exception as e:
tb = traceback.format_exc()
return "Cannot load /{}: {} <pre>\n{}</pre>".format(name, e, tb)
return rendered
if __name__ == '__main__':
app.run()
templates/debug.html
的内容:
<!DOCTYPE html>
<html
xmlns="http://www.w3.org/1999/xhtml"
xmlns:py="http://geshi.edgewall.org/"
>
<body>
<p>Messages is a ${str(type(messages))} of length ${len(messages)}</p>
<p>Messages:</p>
<pre>
${'\n'.join(m + "!" for m in messages)}
</pre>
</body>
</html>
templates/hello.html
的内容:
<!DOCTYPE html>
<html
xmlns="http://www.w3.org/1999/xhtml"
xmlns:py="http://geshi.edgewall.org/"
>
<body>
<h1>Messages</h1>
<ul>
<li py:for="msg in messages">
$msg
</li>
</ul>
</body>
</html>
当我访问http://localhost:5000/debug
时,一切似乎都按预期工作,但当我运行http://localhost:5000/hello
时,我得到了#34;无法渲染/你好:&#39; msg&#39;未定义&#34;
答案 0 :(得分:3)
您在命名空间定义中缺少'n'。它目前正在读取 'xmlns:py =“http://geshi.edgewall.org/”'但它应该是'xmlns:py =“http://genshi.edgewall.org/”'。这导致Genshi无法识别'py:for'属性,然后愉快地尝试评估'$ msg'而没有任何'for msg in messages'来定义变量。