This project is for mocking up a large scale openstack environment for performance testing of cloud management system

We take the name Lasagne because it has "many stacks".

Lasagne (/ləˈzænjə/ or /ləˈzɑːnjə/ or /ləˈsɑːnjə/, Italian pronunciation: [laˈzaɲɲe], singular lasagna) are wide, flat-shaped pasta, and possibly one of the oldest types of pasta.[1] The word "lasagne", and, in many non-Italian languages, the singular "lasagna", can also refer to a dish made with several layers of lasagne sheets alternated with sauces and various other ingredients.

Architecture

Proof of Concept

 SUT   |  MockStack
+-----+ | +-------+   +---------+   +--------+   +----------+
|     +-+->       +--->         +--->        +--->          |
| CMS | | | Faked |   | Crafter |   | Actual |   | devstack |
|     <-+-+       <---+         <---+        <---+          |
+-----+ | +-------+   +---------+   +--------+   +----------+
        |

CMS

Cloud Management System to be tested, e.g. OpenStack Client

Faked Facade

Cache of actual request and mocked response

input: actual request from CMS
output: return cached response if hit, else forward the request to Crafter to get one

The cache is indexed on full request.

Crafter

Fake a response from a matched record in Actual Repository

input: request missed in Faked Facade
output: faked response based on matched record in Actual Repository

To create a fake response, the request need to be modified in order to route it to a valid devstack instance. It may include not only the content of request, but also the time characteristics.

Actual Repository

Cache of actual request and actual response

input: modified request by Crafter
output: return cached response if hit, else forward the request to devstack to get one

The cache can be index on API endpoints, i.e. one record for each API.

devstack

An actual devstack instance to provide base response

input: request missed in Actual Repository
output: response from devstack

Faker engine

A fake response could be generated by randomizing the values in a actual response. But it could be difficult to manage the mapping, especially when there are multi-level dependency, e.g. when the OSC received a faked response, it may send a second step request and expecting a response related to the previous one.

Scale Up

Multiple devstack could be used to provide more samples of actual traffic.

Implementation

Faked Facade: virtual hosts on nginx
Crafter: mitmproxy with scripting
Actual Repository: key-value storage in redis

Lasagne

Contents