I am working on a Flask project and I am using marshmallow to validate user input. Below is a code snippet:
def create_user():
in_data = request.get_json()
data, errors = Userschema.load(in_data)
if errors:
return (errors), 400
fname = data.get('fname')
lname = data.get('lname')
email = data.get('email')
password = data.get('password')
cpass = data.get('cpass')
When I eliminate the errors
part, the code works perfectly. When I run it as it is, I get the following error:
builtins.ValueError
ValueError: too many values to unpack (expected 2)
Traceback (most recent call last)
File "/home/..project-details.../venv3/lib/python3.6/site-packages/flask/app.py", line 2000, in call
error = None
ctx.auto_pop(error)
def __call__(self, environ, start_response):
"""Shortcut for :attr:`wsgi_app`."""
return self.wsgi_app(environ, start_response)
def __repr__(self):
return '<%s %r>' % (
self.__class__.__name__,
self.name,
Note: The var in_data
is a dict.
Any ideas??
I recommend you check your dependency versions. Per the Marshmallow API reference, schema.load returns:
Changed in version 3.0.0b7: This method returns the deserialized data rather than a (data, errors) duple. A ValidationError is raised if invalid data are passed.
I suspect python is trying to unpack the dict (returned as a singular object) into two variables. The exception is raised because there is nothing to pack into the 'errors' variable. The below reproduces the error:
d = dict()
d['test'] = 10101
a, b = d
print("%s : %s" % (a, b))
来源:https://stackoverflow.com/questions/51817237/python-flask-marshmallowvalueerror-too-many-values-to-unpack-expected-2