《Flask Web开发》学习笔记之bug--（4）【AttributeError: type object 'datetime.datetime' has no attribute 'utnow'】

from datetime import datetimefrom flask import Flask, render_templatefrom flask_script import Managerfrom flask_bootstrap import Bootstrapfrom flask_moment import Momentfrom flask_wtf import Formfrom wtforms import StringField, SubmitFieldfrom wtforms.validators import Requiredclass NameForm(Form):name = StringField('What is your name?', validators=[Required])submit = SubmitField('Submit')app = Flask(__name__)app.config['SECRET_KEY'] = 'hard to guess string'manager = Manager(app)bootstrap = Bootstrap(app)moment = Moment(app)@app.errorhandler(404)def page_not_found(e):return render_template('404.html'), [e-mail](500)def internal_server_error(e):return render_template('500.html'), [e-mail]('/')def index():return render_template('index.html', current_time=datetime.utnow())@app.route('/user/<name>')def user(name):return render_template('user.html', name=name)if __name__ == '__main__':manager.run()

$ python3 hello.py runserver --host 0.0.0.0

报错：

* Running on http://0.0.0.0:5000/ (Press CTRL+C to quit)[2017-07-13 14:05:19,132] ERROR in app: Exception on / [GET]Traceback (most recent call last):  File "/home/henry/.local/lib/python3.5/site-packages/flask/app.py", line 1982, in wsgi_app    response = self.full_dispatch_request()  File "/home/henry/.local/lib/python3.5/site-packages/flask/app.py", line 1614, in full_dispatch_request    rv = self.handle_user_exception(e)  File "/home/henry/.local/lib/python3.5/site-packages/flask/app.py", line 1517, in handle_user_exception    reraise(exc_type, exc_value, tb)  File "/home/henry/.local/lib/python3.5/site-packages/flask/_compat.py", line 33, in reraise    raise value  File "/home/henry/.local/lib/python3.5/site-packages/flask/app.py", line 1612, in full_dispatch_request    rv = self.dispatch_request()  File "/home/henry/.local/lib/python3.5/site-packages/flask/app.py", line 1598, in dispatch_request    return self.view_functions[rule.endpoint](**req.view_args)  File "hello.py", line 32, in index    return render_template('index.html', current_time=datetime.utnow())AttributeError: type object 'datetime.datetime' has no attribute 'utnow'127.0.0.1 - - [13/Jul/2017 14:05:19] "GET / HTTP/1.1" 500 -Error on request:Traceback (most recent call last):  File "/home/henry/.local/lib/python3.5/site-packages/werkzeug/serving.py", line 209, in run_wsgi    execute(self.server.app)  File "/home/henry/.local/lib/python3.5/site-packages/werkzeug/serving.py", line 197, in execute    application_iter = app(environ, start_response)  File "/home/henry/.local/lib/python3.5/site-packages/flask/app.py", line 1997, in __call__    return self.wsgi_app(environ, start_response)  File "/home/henry/.local/lib/python3.5/site-packages/flask/app.py", line 1985, in wsgi_app    response = self.handle_exception(e)  File "/home/henry/.local/lib/python3.5/site-packages/flask/app.py", line 1547, in handle_exception    return self.finalize_request(handler(e), from_error_handler=True)  File "/home/henry/dev/Flask_Web_Python_Henry/flask_henry/hello.py", line 28, in internal_server_error    return render_template('500.html'), 500  File "/home/henry/.local/lib/python3.5/site-packages/flask/templating.py", line 133, in render_template    return _render(ctx.app.jinja_env.get_or_select_template(template_name_or_list),  File "/home/henry/.local/lib/python3.5/site-packages/jinja2/environment.py", line 869, in get_or_select_template    return self.get_template(template_name_or_list, parent, globals)  File "/home/henry/.local/lib/python3.5/site-packages/jinja2/environment.py", line 830, in get_template    return self._load_template(name, self.make_globals(globals))  File "/home/henry/.local/lib/python3.5/site-packages/jinja2/environment.py", line 804, in _load_template    template = self.loader.load(self, name, globals)  File "/home/henry/.local/lib/python3.5/site-packages/jinja2/loaders.py", line 125, in load    code = environment.compile(source, name, filename)  File "/home/henry/.local/lib/python3.5/site-packages/jinja2/environment.py", line 591, in compile    self.handle_exception(exc_info, source_hint=source_hint)  File "/home/henry/.local/lib/python3.5/site-packages/jinja2/environment.py", line 780, in handle_exception    reraise(exc_type, exc_value, tb)  File "/home/henry/.local/lib/python3.5/site-packages/jinja2/_compat.py", line 37, in reraise    raise value.with_traceback(tb)  File "/home/henry/dev/Flask_Web_Python_Henry/flask_henry/templates/500.html", line 9, in template    {% endlock %}  File "/home/henry/.local/lib/python3.5/site-packages/jinja2/environment.py", line 497, in _parse    return Parser(self, source, name, encode_filename(filename)).parse()  File "/home/henry/.local/lib/python3.5/site-packages/jinja2/parser.py", line 896, in parse    result = nodes.Template(self.subparse(), lineno=1)  File "/home/henry/.local/lib/python3.5/site-packages/jinja2/parser.py", line 878, in subparse    rv = self.parse_statement()  File "/home/henry/.local/lib/python3.5/site-packages/jinja2/parser.py", line 130, in parse_statement    return getattr(self, 'parse_' + self.stream.current.value)()  File "/home/henry/.local/lib/python3.5/site-packages/jinja2/parser.py", line 268, in parse_block    node.body = self.parse_statements(('name:endblock',), drop_needle=True)  File "/home/henry/.local/lib/python3.5/site-packages/jinja2/parser.py", line 165, in parse_statements    result = self.subparse(end_tokens)  File "/home/henry/.local/lib/python3.5/site-packages/jinja2/parser.py", line 878, in subparse    rv = self.parse_statement()  File "/home/henry/.local/lib/python3.5/site-packages/jinja2/parser.py", line 144, in parse_statement    self.fail_unknown_tag(token.value, token.lineno)  File "/home/henry/.local/lib/python3.5/site-packages/jinja2/parser.py", line 97, in fail_unknown_tag    return self._fail_ut_eof(name, self._end_token_stack, lineno)  File "/home/henry/.local/lib/python3.5/site-packages/jinja2/parser.py", line 90, in _fail_ut_eof    self.fail(' '.join(message), lineno)  File "/home/henry/.local/lib/python3.5/site-packages/jinja2/parser.py", line 59, in fail    raise exc(msg, lineno, self.name, self.filename)jinja2.exceptions.TemplateSyntaxError: Encountered unknown tag 'endlock'. Jinja was looking for the following tags: 'endblock'. The innermost block that needs to be closed is 'block'.

注意到：

【

File "hello.py", line 32, in index    return render_template('index.html', current_time=datetime.utnow())AttributeError: type object 'datetime.datetime' has no attribute 'utnow'
】

原来是【utnow()】少了一个字母【c】,加上去了之后就没有这个报错了。