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Python Build a Social Network with Flask Tacocat Challenge The Challenge

Brendan Whiting
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.a{fill-rule:evenodd;}techdegree seal-36
Brendan Whiting
Front End Web Development Techdegree Graduate 84,735 Points
Posted by Brendan Whiting
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Brendan Whiting
Front End Web Development Techdegree Graduate 84,735 Points

AttributeError: 'tuple' object has no attribute '__call__'

I'm going to avoid posting all my tacocat challenge code if I can, it's a mess, just trying to understand this one error message for now.

Here is macros.html from s5v1

{% macro render_field(field) %}
{% if field.errors %}
<div class="u-full-width field-errors">
  <ul>
    {% for error in field.errors %}
    <li>{{ error }}</li>
    {% endfor %}
  </ul>
</div>
{% endif %}
{{ field.label }}
 {{ field(class="u-full-width") }}
{% endmacro %}

I get this Jinja2 error:

File "/home/treehouse/workspace/templates/macros.html", line 12, in <module> {{ field(class="u-full-width") }} AttributeError: 'tuple' object has no attribute 'call'

So what I don't understand is that in the previous app we made, there was a similar line of code where it would appear we are "calling" this tuple like a function.

Here is macros.html from s4v5

{% macro render_field(field) %}
    <div class="field">
        {% if field.errors %}
            {% for error in field.errors %}
                <div class="notification error">{{ error }}</div>
            {% endfor %}
        {% endif %}
        {{ field(placeholder="hey there") }}
    </div>
{% endmacro %}

How is it that {{ field(placeholder="hey there") }} isn't causing the same problem?

3 Answers

Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 68,423 Points
Chris Freeman
Chris Freeman
Treehouse Moderator 68,423 Points

I created a mash-up of your code and my tacocat solution and could not reproduce your error. I did find two other errors in your tacocat.py file. Without the rest of your files, I don't think I can reproduce your error,

  • redirect not defined
  • login_manager.user_loader not defined
# add missing redirect
from flask import redirect

# Hack add missing user_loader -cf
@login_manager.user_loader
def load_user(userid):
    try:
        return models.User.get(models.User.id == userid)
    except DoesNotExist:
        return None

# Hack route -cf
@app.route('/register', methods=('Get', 'Post'))
def register():
    return render_template('index.html', tacos=models.Taco.select())

# Hack route -cf
@app.route('/taco', methods=('Get', 'Post'))
def taco():
    return render_template('index.html', tacos=models.Taco.select())

# Hack route -cf
@app.route('/logout', methods=('Get', 'Post'))
def logout():
    return render_template('index.html', tacos=models.Taco.select())

with this additional code, the mash-up produced:

$ python app_tests.py 
.FF......FF
======================================================================
FAIL: test_empty_db (__main__.TacoViewsTestCase)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "app_tests.py", line 129, in test_empty_db
    self.assertIn("no tacos yet", rv.get_data(as_text=True).lower())
AssertionError: 'no tacos yet' not found in '<!doctype html>\n<html>\n  <head>\n    <title>tacocat</title>\n    <link rel="stylesheet" href="/static/css/normalize.css">\n    <link rel="stylesheet" href="/static/css/skeleton.css">\n    <link rel="stylesheet" href="/static/css/tacocat.css">\n  </head>\n  <body>\n    \n    \n    \n\n    <div class="container">\n      <div class="row">\n        <div class="u-full-width">\n          <nav class="menu">\n              <!-- menu goes here -->\n              \n                <p>welcome!!</p>\n                <a href="/login">log in</a>\n                <a href="/register">sign up</a>\n              \n          </nav>\n          \n\n<form method=\'post\' action=\'\'>\n  <div style="display:none;"><input id="csrf_token" name="csrf_token" type="hidden" value="none"></div>\n  <div class="row">\n    <div class="six columns">\n      \n      \n\n<label for="protein">protein</label>\n <input class="u-full-width" id="protein" name="protein" type="text" value="">\n\n    </div>\n    <div class="six columns">\n      \n      \n\n<label for="shell">shell</label>\n <input class="u-full-width" id="shell" name="shell" type="text" value="">\n\n    </div>\n  </div>\n  <div class="row">\n    <div class="six columns">\n      \n\n<label for="cheese">cheese?</label>\n <input class="u-full-width" id="cheese" name="cheese" type="checkbox" value="y">\n\n    </div>\n    <div class="six columns">\n      \n\n<label for="extras">extras?</label>\n <input class="u-full-width" id="extras" name="extras" type="text" value="">\n\n    </div>\n  </div>\n  <div class="u-full-width">\n    <input type="submit" class="button-primary" value="create">\n  </div>\n</form>\n\n\n        </div>\n      </div>\n      <footer>\n        <p>an mvp web app made with flask on <a href="http://teamtreehouse.com">treehouse</a>.</p>\n      </footer>\n    </div>\n  </body>\n</html>'

======================================================================
FAIL: test_taco_create (__main__.TacoViewsTestCase)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "app_tests.py", line 144, in test_taco_create
    self.assertEqual(rv.status_code, 302)
AssertionError: 200 != 302

======================================================================
FAIL: test_logout (__main__.UserViewsTestCase)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "app_tests.py", line 108, in test_logout
    self.assertEqual(rv.status_code, 302)
AssertionError: 200 != 302

======================================================================
FAIL: test_registration (__main__.UserViewsTestCase)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "app_tests.py", line 86, in test_registration
    self.assertEqual(rv.status_code, 302)
AssertionError: 200 != 302

----------------------------------------------------------------------
Ran 11 tests in 22.317s

FAILED (failures=4)
Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 68,423 Points
Chris Freeman
Chris Freeman
Treehouse Moderator 68,423 Points

Your code from macro.html is exactly the code I used to passed the challenge. Many times an error is cause by some upstream activity meaning that macro.html is at the end of the process tacocat.login() → login.html → macros.html. So it could be an error with a field that is passed down the chain.

What does your tacocat.py and login.html look like?

Brendan Whiting
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
Brendan Whiting
Front End Web Development Techdegree Graduate 84,735 Points
Brendan Whiting
.a{fill-rule:evenodd;}techdegree seal-36
Brendan Whiting
Front End Web Development Techdegree Graduate 84,735 Points

My code right now is kind of a disaster. I had this strategy of trying to write code to pass each test, rather than trying to make a fully formed app and then try and pass the tests. But anyways:

tacocat.py

from flask import Flask, render_template, flash, url_for
from flask.ext.bcrypt import check_password_hash
from flask.ext.login import (LoginManager, login_user, logout_user,
                             login_required, current_user)

import forms
import models

DEBUG = True
PORT = 8000
HOST = '0.0.0.0'

app = Flask(__name__)
app.secret_key = 'lalal!'

login_manager = LoginManager()
login_manager.init_app(app)
login_manager.login_view = 'login'

@app.route('/')
def index():
    form = forms.TacoForm()
    return render_template('taco.html', form=form)

@app.route('/login', methods=('GET', 'POST'))
def login():
    form = forms.LoginForm()
    if form.validate_on_submit():
        try:
            user = models.User.get(models.User.email == form.email.data)
        except models.DoesNotExist:
            flash("Your email or password doesn't match!", "error")
        else:
            if check_password_hash(user.password, form.password.data):
                login_user(user)
                flash("You've been logged in!", "success")
                return redirect(url_for('index'))
            else:
                flash("Your email or password doesn't match!", "error")
    return render_template('login.html', form=form)


if __name__ == '__main__':
    models.initialize()
    try:
        models.User.create_user(
            email='kenneth@teamtreehouse.com',
            password='password',
        )
    except ValueError:
        pass
    app.run(debug=DEBUG, host=HOST, port=PORT)

login.html

{% extends 'layout.html' %}
{% from 'macros.html' import render_field %}

{% block content %}
<form method='POST' action=''>
  {{ form.hidden_tag() }}
  <div class="row">
    <div class="six columns">
      {{ render_field(form.email) }}
    </div>
    <div class="six columns">
      {{ render_field(form.password) }}
    </div>
  </div>
  <div class="u-full-width">
    <input type="submit" class="button-primary" value="Login">
  </div>
</form>
{% endblock %}
Chris Grazioli
Chris Grazioli
31,225 Points
Chris Grazioli
Chris Grazioli
31,225 Points

do you need to import redirect?