Partial success handling in Rest API - Step-by-Step Execution

Concept Flow - Partial success handling

Client sends request

↓

Server processes items

↓

Check each item result

↓

Collect successes

↓

Build partial success response

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Send response to client

The server processes each item in a request, collects successes and failures separately, then sends a response showing which parts succeeded and which failed.

Execution Sample

Rest API

POST /batch_process
Request: {items: [1,2,3]}
Process each item:
 - item 1: success
 - item 2: fail
 - item 3: success
Response: {successes: [1,3], failures: [2]}

This example shows a batch API processing multiple items, reporting which succeeded and which failed.

Execution Table

Step	Item	Process Result	Success List	Failure List	Action
1	1	Success	[1]	[]	Add to success list
2	2	Failure	[1]	[2]	Add to failure list
3	3	Success	[1,3]	[2]	Add to success list
4	-	-	[1,3]	[2]	Build response with partial success
5	-	-	[1,3]	[2]	Send response to client

💡 All items processed; response sent with successes and failures separated

Variable Tracker

Variable	Start	After 1	After 2	After 3	Final
success_list	[]	[1]	[1]	[1,3]	[1,3]
failure_list	[]	[]	[2]	[2]	[2]

Key Moments - 2 Insights

Why do we keep successes and failures separate instead of stopping at the first failure?

Because the execution_table shows the server processes all items (rows 1-3) before responding, allowing partial success reporting.

How does the server know which items succeeded or failed?

The process result column in the execution_table (rows 1-3) shows each item's outcome, which updates success_list or failure_list accordingly.

Visual Quiz - 3 Questions

Look at the execution_table at step 2. What is the failure_list value?

A [2]

B []

C [1]

D [1,3]

💡 Hint

Check the failure_list column at step 2 in the execution_table.

At which step does the server build the partial success response?

A Step 1

B Step 3

C Step 4

D Step 5

💡 Hint

Look at the Action column in the execution_table for the step mentioning response building.

If item 2 had succeeded, how would success_list look after step 3?

A [1,3]

B [1,2,3]

C [2,3]

D [1,2]

💡 Hint

Refer to variable_tracker success_list values and imagine item 2 success at step 3.

Concept Snapshot

Partial success handling in REST APIs:
- Process each item independently
- Collect successes and failures separately
- Respond with both lists
- Allows client to know what worked and what failed
- Improves robustness in batch operations

Full Transcript

Partial success handling means when a server processes multiple items in one request, it does not stop at the first failure. Instead, it processes all items, keeps track of which succeeded and which failed, and sends a response showing both lists. This helps clients understand exactly what worked and what did not. The execution table shows each item processed step-by-step, updating success and failure lists. The server builds the response after all items are processed, then sends it back. This approach is common in batch APIs to improve reliability and feedback.