Statelessness requirement in Rest API - Step-by-Step Execution

Concept Flow - Statelessness requirement

Client sends request

↓

Server receives request

↓

Server processes request WITHOUT storing client info

↓

Server sends response

↓

Client receives response

↓

Next request treated as new, no memory of previous

Each request from client to server is independent; the server does not remember past requests.

Execution Sample

Rest API

GET /user/123 HTTP/1.1
Host: example.com
Authorization: Bearer token123

Response: {"id":123,"name":"Alice"}

Client sends a request with all needed info; server responds without storing session data.

Execution Table

Step	Action	Server State	Client Info Stored?	Response Sent
1	Client sends GET /user/123 with token	No stored data	No	User data for id 123
2	Server processes request using token	No stored data	No	User data sent
3	Server finishes request	No stored data	No	Response complete
4	Client sends next request GET /user/456 with token	No stored data	No	User data for id 456
5	Server processes new request independently	No stored data	No	User data sent
6	Server finishes second request	No stored data	No	Response complete

💡 Server never stores client info; each request is handled independently.

Variable Tracker

Variable	Start	After Step 1	After Step 4	Final
Server Stored Data	None	None	None	None
Client Request Info	None	Request with token123	Request with token456	Request with token456

Key Moments - 2 Insights

Why doesn't the server remember the client's previous request?

Because the server does not store any client info between requests, as shown in execution_table rows 1-3 and 4-6.

How does the server know who the client is if it doesn't store data?

The client sends all needed info (like tokens) with each request, so the server can authenticate without stored data (see execution_table step 1 and 4).

Visual Quiz - 3 Questions

Look at the execution_table, what is the server's stored data after step 3?

A User session info stored

B No stored data

C Partial client info stored

D Error state

💡 Hint

Check the 'Server State' column at step 3 in execution_table.

At which step does the server process a new request independently?

A Step 2

B Step 4

C Step 5

D Step 3

💡 Hint

Look for 'Server processes new request independently' in execution_table.

If the server started storing client info, which variable in variable_tracker would change?

A Server Stored Data

B Client Request Info

C Response Sent

D None

💡 Hint

Server Stored Data tracks what the server keeps between requests.

Concept Snapshot

Statelessness means each client request is independent.
Server does NOT keep client info between requests.
Client must send all needed info each time.
This makes servers simpler and scalable.
Example: REST APIs follow this rule.

Full Transcript

Statelessness requirement means the server treats every client request as new and independent. The server does not save any information about the client between requests. Instead, the client sends all necessary data, like authentication tokens, with each request. This approach simplifies server design and helps it handle many clients efficiently. The execution table shows the server processing two separate requests without storing any client data. Variables tracking server stored data remain empty throughout. This is the core idea behind REST API statelessness.