Validate Objects Against a Schema | Dataford Interview Questions

Amplitude Experiment and Analytics services receive structured event payloads. Implement a validator that checks whether an object conforms to a recursive schema containing required fields, data types, nested objects, and arrays.

The schema uses nodes with type, and optionally required, properties, items, and additionalProperties. Supported types are string, number, boolean, null, array, and object. Return an object containing valid and an ordered errors list. Report errors in traversal order using paths such as payload.user.id and payload.items[0]. A missing required field should produce missing: <path>. A type mismatch should produce expected <type>: <path>. When additionalProperties is false, report unexpected: <path> for undeclared fields.

Constraints

The payload contains JSON-compatible values only.
The schema is valid and has a root node.
There are at most 10^4 total payload values and schema nodes.
Property names are non-empty strings.
Required-field and object-key order must be preserved in the errors list.

Function Signature

def validate_payload(payload, schema):

Your question is Validate Objects Against a Schema. Start with the requirements in the Question tab.

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Problem

Constraints

The payload contains JSON-compatible values only.
The schema is valid and has a root node.
There are at most 10^4 total payload values and schema nodes.
Property names are non-empty strings.
Required-field and object-key order must be preserved in the errors list.

Function Signature

def validate_payload(payload, schema):

Your question is Validate Objects Against a Schema. 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.