Load Balancer Registration | Dataford Interview Questions

Create a LoadBalancer class that has a method to register backend instances. Each backend instance address should be unique, it should not be possible to register the same address two times. Load balancer should accept up to 10 backend instances. The code should be production ready. The Loadbalancer will be released as a library.

Asked in the technical round 1 stage. Java, no Spring, unit tests with JUnit expected. Reported follow-up: implement get() so repeated calls randomly return one registered backend.

For grading, implement the equivalent Python behavior through run_load_balancer(operations). Each operation is register, with an address, or get. Return registration results as true or an error label, and return the selected address for get.

Constraints

Each operation has type register or get.
A registered address is a non-empty string.
At most 11 registration operations are supplied.
The balancer accepts at most 10 unique addresses.
A get operation may return any currently registered address.

Function Signature

def run_load_balancer(operations):

Your question is Load Balancer Registration. 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

Asked in the technical round 1 stage. Java, no Spring, unit tests with JUnit expected. Reported follow-up: implement get() so repeated calls randomly return one registered backend.

Constraints

Each operation has type register or get.
A registered address is a non-empty string.
At most 11 registration operations are supplied.
The balancer accepts at most 10 unique addresses.
A get operation may return any currently registered address.

Function Signature

def run_load_balancer(operations):

Your question is Load Balancer Registration. 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.