Django: invalid literal for int() with base 10

Question

I am new to Django and trying to pass an author's name to a view and filter out quote objects based on the author's name. here are the codes:

models.py

class Author(models.Model):
    author_name = models.CharField(max_length=50, default='unknown')
    author_info = models.TextField(max_length=1000)


class Quote(models.Model):
    author = models.ForeignKey(Author)
    quote = models.TextField(max_length=500)
    category= models.ForeignKey(Category)
    pub_date = models.DateTimeField('date published')

urls.py:

url(r'^quotes/(?P<name>\w+)/$', 'quotes.views.quotesbyauthor'),

views.py

def quotesbyauthor(request, name):
    aquotelist = Quote.objects.filter(author__exact = name)
    return render_to_response(quotes_by_author.html, {'aquotelist': aquotelist })

However I get this error when I try to get http://127.0.0.1:8000/quotes/you/ ('you' is a test author object, already created)

ValueError at /quotes/you/

invalid literal for int() with base 10: 'you'

Request Method:     GET
Request URL:    http://127.0.0.1:8000/quotes/you/
Django Version:     1.3.1
Exception Type:     ValueError
Exception Value:    

invalid literal for int() with base 10: 'you'

Exception Location:     /home/qliq/djenv/lib/python2.6/site-packages/django/db/models/fields/__init__.py in get_prep_value, line 479
Python Executable:  /home/qliq/djenv/bin/python
Python Version:     2.6.6
Python Path:    

['/home/qliq/djenv/quoteapp',
 '/home/qliq/djenv/lib/python2.6/site-packages/distribute-0.6.10-py2.6.egg',
 '/home/qliq/djenv/lib/python2.6/site-packages/pip-0.7.2-py2.6.egg',
 '/home/qliq/djenv/lib/python2.6',
 '/home/qliq/djenv/lib/python2.6/plat-linux2',
 '/home/qliq/djenv/lib/python2.6/lib-tk',
 '/home/qliq/djenv/lib/python2.6/lib-old',
 '/home/qliq/djenv/lib/python2.6/lib-dynload',
 '/usr/lib/python2.6',
 '/usr/lib/python2.6/plat-linux2',
 '/usr/lib/python2.6/lib-tk',
 '/home/qliq/djenv/lib/python2.6/site-packages']

I appreciate your help to resolve this.

Answer 1

You want to search on the author's author_name field, not the id.

Quote.objects.filter(author__author_name=name)

With your current search, author__exact, Django expects name to be the id of the author, so gives an error because you is not an integer.

Answer 2

aquotelist = Quote.objects.filter(author__author_name__exact = name)

Try changing the corresponding line to the above. The way you have it now, you are matching author to the given name, but author is probably considered by its ID here, definitely not by its author_name. The format is as follows:

Quote.objects.filter([model]__[field]__exact = [whatever])

Answer 3

I have faced and solved similar issue, focus on attribute : author = models.ForeignKey(Author) django expect that you pass an Instance of Author class to the author field. When you search django want to get a id (a integer number of this Instance): so to get :

aquotelist = Quote.objects.filter(author__exact = name)

you have to start by :

1. create obj_Author = Author.objects.get(author_name = name)

2. aquotelist = Quote.objects.get(author__exact = obj_Author.id)

PS: ( I used get() in my example but if you expect to get multiple record, you can you use filter() and modify something. but main point is that because you work with a "ForeignKey field" so you need to give it a id like obj_Author.id. )