THINK YOUR SOFTWARE IS FAULT TOLERANT? PROVE ITCHRISTOPHER BATEY @CHBATEY

TESTING

FEATURES WITHOUT AUTOMATED TESTS ARE MERELY RUMOURS

HAPPY PATH

UNHAPPY PATH

YOU DON’T KNOW A SERVICE IS FAULT TOLERANT IF YOU DON’T TEST FAULTS

PROTOCOL LEVEL TEST DOUBLE

YOUR SERVICEPROTOCOL

LEVEL TEST

DOUBLE

TEST

PRIMING

Real HTTP/TCP

Examples

REST Driver

Wiremock

MOCO

Stubbed Cassandra

DETERMINISTICALLY CREATE ANY SCENARIO

TO SURVIVE THE CHAOS MONKEY

TO SURVIVE REALITY

ENOUGH FLUFF

Pesky User (that’s us)

using cURL

Enterprise hello world

A different team’s software (probably

rubbish)

Crazy distributed database

HTTP /name

TCP surname

Dependency VM

Wiremock Stubbed Cassandra

192.168.2.2

Wiremock

192.168.2.2

Enterprise hello world

localhost 192.168.2.1

PRIMING

HITTING THE SERVICE

DEMO TIME

Wiremock

192.168.2.2

Enterprise hello world

localhost 192.168.2.1

Delay is here

Wiremock

192.168.2.2

Enterprise hello world

localhost 192.168.2.1

Delay is here

Wiremock

192.168.2.2

Enterprise hello world

localhost 192.168.2.1

Delay is here

Wiremock

192.168.2.2

Enterprise hello world

localhost 192.168.2.1

Delay is here

NOT JUST FOR HTTP

PRODUCTION?

Application

Issues here

PRODUCTION?ApplicationApplicationApplicationApplicationApplication

ApplicationApplicationApplicationApplicationApplication

ApplicationApplicationApplicationApplicationApplication

DC1

DC2

Distributed failuressuccessread_request_timeoutunavailablewrite_request_timeoutserver_errorprotocol_errorbad_credentialsoverloadedis_bootstrappingtruncate_error

READ TIMEOUT

Application C

R1

R2

R3C=QUROUM

Replication factor: 3

timeout

timeout

Read timeout

DEMO TIME

ResourcesWiremock: http://wiremock.org/

Awesome TC guide: http://blog.edseek.com/~jasonb/articles/traffic_shaping/

Stubbed Cassandra: http://scassandra.org

Wireshark: https://www.wireshark.org/

Saboteur: https://github.com/tomakehurst/saboteur

Example app + VM: https://github.com/chbatey/vagrant-wiremock-saboteur

THANKS FOR LISTENING@CHBATEY