request.session lesen und schreiben

Think of request.session as a dictionary that follows one visitor. You read and write keys exactly like any Python dict.

To remember something, just assign a key. Here we save a cart list so the visitor keeps their items across pages.

Read a key back the dictionary way. Using get with a default avoids a crash when the key has not been set yet.

To grow a cart, read it, change the Python object, then assign it back so Django notices the update and saves it.

When you mutate a nested object in place, set session.modified to True so Django knows it must persist the change.

Remove a single value with del, just like a normal dictionary, to forget one piece of session state.

Use the in operator to test whether a value exists before you read it, which keeps your view logic clean.

Session values must be JSON serializable by default. Lists, dicts, strings, and numbers are fine; model instances are not.

To wipe all session data for a visitor, call flush. It deletes the data and rotates the session key, handy at logout.

Override the global timeout for one visitor with set_expiry. Passing zero ends the session when the browser closes.

You rarely call save yourself. The middleware writes the session at the end of each request whenever you changed it.

You used request.session like a dict: write, read with get, delete, flush, and set expiry. Remember to flag in-place edits as modified. Next up, the messages framework. 💬