Django Forms

Introduction to Django Forms for Django Girls × Taipei.py workshop.

Transcript

1. Django Forms
   

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2. Django Forms
   • Forms?
   • Forms!
   • Model forms
   

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3. Web Page
   

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4. Web Page with Form
   submit
   

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5. method="POST"
   enctype="multipart/form-data">
   
   
   
   

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7. method="post"
   enctype="multipart/form-data">
   • Where to send
   • URL
   • Default: "" (current URL)
   

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8. method="post"
   enctype="multipart/form-data">
   • How to send
   • Either get or post
   • Get: postcard
   • Post: Enveloped
   • Default: get
   

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9. method="post"
   enctype="multipart/form-data">
   • How to read
   • application/x-www-form-urlencoded
   • Default
   • multipart/form-data
   • Form contains file
   

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10. GET Submission
    Query string
    

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11. POST Submission
    "GET /admin/ HTTP/1.1" 302 0
    "GET /admin/login/?next=/admin/ HTTP/1.1" 200 1679
    "POST /admin/login/?next=/admin/ HTTP/1.1" 302 0
    "GET /admin/ HTTP/1.1" 200 3407
    

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12. method="POST"
    enctype="multipart/form-data">
    
    
    
    

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13. 
    
    Submit
    
    

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14. 
    
    Submit
    
    

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15. method="POST"
    enctype="multipart/form-data">
    
    
    
    

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16. Django Forms!
    

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17. Models
    Database
    Django forms
    HTML forms
    

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18. from django import forms
    class MessageForm(forms.Form):
    name = forms.CharField(
    max_length=100,
    )
    title = forms.CharField(
    max_length=100, required=False,
    )
    content = forms.CharField(
    widget=forms.Textarea,
    )
    

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19. from .forms import MessageForm
    def message_board(request):
    form = MessageForm()
    return render(
    request, 'message_board.html',
    {'form': form},
    )
    

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20. 
    {% csrf_token %}
    {{ form.as_p }}
    ૹग़
    
    

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21. 
    {% csrf_token %}
    {{ form.as_p }}
    ૹग़
    
    ?
    

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22. CSRF Token
    • Cross Site Request Forgery
    protection
    • “Recognise” whether a form is legit
    • Protect the server from malicious
    changes
    

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25. class Message(models.Model):
    name = models.CharField(
    max_length=100,
    )
    title = models.CharField(
    max_length=100, blank=True,
    )
    content = models.TextField()
    created_at = models.DateTimeField(
    auto_now_add=True,
    )
    

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26. class Message(models.Model):
    name = models.CharField(
    max_length=100,
    )
    title = models.CharField(
    max_length=100, blank=True,
    )
    content = models.TextField()
    created_at = models.DateTimeField(
    auto_now_add=True,
    )
    

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27. class MessageForm(forms.Form):
    # ...
    def save(self):
    data = self.cleaned_data
    message = Message(
    name=data['name'],
    title=data['title'],
    content=data['content'],
    )
    message.save()
    return message
    

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28. class MessageForm(forms.Form):
    # ...
    def save(self):
    data = self.cleaned_data
    message = Message(
    name=data['name'],
    title=data['title'],
    content=data['content'],
    )
    message.save()
    return message
    

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29. def message_board(request):
    if request.method == 'POST':
    form = MessageForm(request.POST)
    if form.is_valid():
    form.save()
    else:
    form = MessageForm()
    return render(
    request, 'message_board.html',
    {'form': form},
    )
    

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30. Further Reading
    • Model forms
    • Form factories
    • Custom “cleaning”
    

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31. Exercises
    • Implement message form
    • Implement message model,
    save POST-ed form to it
    • Get messages from database
    • Display messages in template
    

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32. Hint
    {% for m in messages %}
    
    {{ m.name }}
    {{ m.title }}
    {{ m.content|linebreaks }}
    
    {% endfor %}
    Message.obejcts.order_by('-created_at')
    

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