New testing framework

[akiradeveloper]

In the integration-tests, all tests are done in a single docker container, not running containers. The trick is running a process and the servers are bind to different ports of the localhost.

This is because of these two reasons:

1. Running a container inside container isn't recommended way of using Docker
2. Starting a Docker image of kvs-server was very heavy and it took unreasonable time to complete a test with large cluster

Recently, I found the second one was due to my mistake that I didn't minimize the docker image. The docker image with a Rust tool-set and others is like 2GB but when they are reduced by docker-slim, it is 20MB. Loading a 2GB image to starting a container took maybe a few seconds.

If we run each kvs-server in separate container, we can use pumba to emulate network failure. Chaos testing can also be done.

However, downside of the change could be coverage test is broken because chances are profraw files are dumped to separate container filesystems and we can't collect them.

[akiradeveloper]

However, downside of the change could be coverage test is broken because chances are profraw files are dumped to separate container filesystems and we can't collect them.

It seems the profraw files are dumped under the directory that test program exists. (currently integrate-tests/cov) If so, all the profraw files will be dumped inside a tester container or host.

[akiradeveloper]

Now the test is run with docker containers.