fault.py

import boto3
import random

def getconfig(key):
    return {
        'api-delay-services': ['ec2'],
        'api-delay-range': [0, 3],
        'api-delay-rate': 10,        
        'aws-fault-services': ['s3', 'dynamodb'],
        'api-fault-rate': 10
    }.get(key)


class BotoFaultInjector(object):

    def __init__(self):
        self._regid = None
        self.delay_services = getconfig('api-delay-services')
        self.delay_range = getconfig('api-delay-range')
        self.delay_rate = getconfig('api-delay-rate')
        self.fault_service = getconfig('api-fault-services')
        self.fault_rate = getconfig('api-fault-rate')
        

    def attach(self, s):
        self._regid = s.register('after-call.*.*', self.invoke)
        
    def invoke(self, http_response, parsed, model, **kwargs):
        if model.name in delay_services:
            if random.randrange(0, 100) < self.delay_rate:
                time.sleep(random.randrange(*self.delay_range))

        if model.name in fault_services:
            if random.rangrange(0, 100) < self.delay_rate:
                http_response["Error"] = {
                    "Message": "Not Found",
                    "Code": "ResourceNotFoundException"
                }
                http_response['status_code'] = 400



if __name__ == '__main__':
    boto3.client('ec2')
    fault_injector = BotoFaultInjector()
    fault_injector.attach(boto3.DEFAULT_SESSION)