Flatten Nested Call Metadata | Dataford Interview Questions

Given a JSON payload of nested call metadata, write a Python function to flatten the data and extract specific nested fields. Implement flatten_call_metadata(payload) for a payload containing a calls array. Return one flat dictionary per call with the keys id, direction, status, agent_id, customer_phone, started_at, ended_at, and recording_url; use None when an optional nested field is absent.

Constraints

payload is a dictionary containing a calls list.
1 <= len(payload["calls"]) <= 500
Each call is a dictionary.
Nested metadata can be absent, but every output dictionary contains the same eight keys.
Input values are JSON-compatible primitives, dictionaries, lists, or null.

Function Signature

def flatten_call_metadata(payload):

Your question is Flatten Nested Call Metadata. Start with the requirements in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.

Problem

Constraints

payload is a dictionary containing a calls list.
1 <= len(payload["calls"]) <= 500
Each call is a dictionary.
Nested metadata can be absent, but every output dictionary contains the same eight keys.
Input values are JSON-compatible primitives, dictionaries, lists, or null.

Function Signature

def flatten_call_metadata(payload):

Your question is Flatten Nested Call Metadata. Start with the requirements in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.