View base class in Django - Step-by-Step Execution

Concept Flow - View base class

Request received

↓

View base class dispatch

↓

Determine HTTP method

↓

Call get() method

↓

Call post() method

↓

Call corresponding method or 405

↓

Return HttpResponse

The View base class receives a request, checks its HTTP method, calls the matching method like get() or post(), then returns a response.

Execution Sample

Django

from django.views import View
from django.http import HttpResponse

class MyView(View):
    def get(self, request):
        return HttpResponse('Hello from GET')

Defines a simple View subclass that responds to GET requests with a text message.

Execution Table

Step	Action	Request Method	Method Called	Response
1	Request received by MyView	GET	dispatch()	None yet
2	dispatch() checks method	GET	get()	None yet
3	get() executes	GET	get()	HttpResponse('Hello from GET')
4	Response returned to client	GET	get()	HttpResponse with content 'Hello from GET'

💡 Request handled by get() method, response returned

Variable Tracker

Variable	Start	After Step 1	After Step 2	After Step 3	Final
request.method	N/A	GET	GET	GET	GET
method_called	None	dispatch	get	get	get
response	None	None	None	HttpResponse('Hello from GET')	HttpResponse('Hello from GET')

Key Moments - 2 Insights

Why does the dispatch() method call get() for a GET request?

dispatch() looks at request.method and calls the matching method like get() for GET, as shown in execution_table step 2.

What happens if the HTTP method is not defined in the View subclass?

dispatch() will return a 405 Method Not Allowed response because no matching method exists, not shown here but implied by dispatch logic.

Visual Quiz - 3 Questions

Look at the execution table, which method is called at step 2 for a GET request?

A get()

B post()

C dispatch()

D put()

💡 Hint

Check the 'Method Called' column at step 2 in the execution_table.

At which step is the HttpResponse created?

A Step 2

B Step 3

C Step 1

D Step 4

💡 Hint

Look at the 'Response' column to see when HttpResponse appears.

If the request method was POST but post() is not defined, what would happen?

A dispatch() calls get() instead

B dispatch() ignores the request

C dispatch() returns 405 Method Not Allowed

D dispatch() raises an error

💡 Hint

Recall key_moments about dispatch behavior when method is missing.

Concept Snapshot

View base class handles HTTP requests.
It uses dispatch() to route requests by method.
Define get(), post(), etc. to handle methods.
If method missing, returns 405 error.
Returns HttpResponse to client.

Full Transcript

The Django View base class receives an HTTP request and uses its dispatch() method to check the request's HTTP method. Depending on the method, dispatch() calls the corresponding method like get() for GET requests or post() for POST requests. The called method processes the request and returns an HttpResponse. If the method is not implemented, dispatch() returns a 405 Method Not Allowed response. This flow ensures each HTTP method is handled properly by the View subclass.