User Guide#

About#

This project starts the database container, and optionally (only available via API) also a test container. Both containers exist in the same Docker network. This allows you to connect from the test container to the Docker-DB container. Furthermore, this package provides two utility tasks which allow the population of some test data and upload of files to the BucketFS. Besides the test container, you can also access the Exasol database and the Bucket-FS from the host via forwarded ports.

Comparison to Docker-DB and the Exasol Testcontainers#

This project uses the Docker-DB, but it does the configuration, setup and startup for you. For example, it waits until the Database and the Bucket-FS accept connections. It also provides tasks which simplify the population the database with test data and upload of files to the BucketFS.
The Exasol Testcontainers provide similar features for Java integration tests, so if you have a Java project use the Exasol Testcontainer, because they are more integrated in the Java ecosystem than this project. Testcontainers are designed to integrate with popular unit testing frameworks like JUnit4, JUnit5 and Spock. Most notably, lifecycle management of containers controlled by the tests lifecycle.

However, if you have a project in any other language you can use this project to start a test Exasol database via a command line interface. And if you have a Python project, you also have the possibility to start the additional test-container, which is started in the same docker network as the database.

Prerequisites#

In order to start a Docker-DB Test Environment, you need:

Tested Operating System:
- Linux
- Mac OS X with Docker Desktop on Mac and Intel processor
- Windows is currently not supported
Docker with privileged mode
At least 2 GiB RAM
We recommend at least 15 GB free disk space on the partition where Docker stores its images and containers. On Linux Docker typically stores the images under /var/lib/docker.

Getting started#

Clone the repository

git clone https://github.com/exasol/integration-test-docker-environment

Starting the test environment:

./start-test-env spawn-test-environment --environment-name <NAME>

or if you work on the code of the Test Environment (requires Python >=3.8 with poetry):

./start-test-env-with-poetry spawn-test-environment --environment-name <NAME>

Shutdown of the test environment is currently done manual.

Options#

The following options are available to customize the test environment.

Usage: main.py spawn-test-environment [OPTIONS]

  This command spawn a test environment with a docker-db container.

Options:
  --environment-name TEXT         Name of the docker environment. This name
                                  gets used as suffix for the container
                                  db_container_<name> and
                                  test_container_<name>  [required]

  --database-port-forward INTEGER
                                  Host port to which the database port gets
                                  forwarded

  --bucketfs-port-forward INTEGER
                                  Host port to which the BucketFS port gets
                                  forwarded

  --ssh-port-forward INTEGER
                                  Host port to which the SSH port gets
                                  forwarded

  --db-mem-size TEXT              The main memory used by the database. Format
                                  <number> <unit>, e.g. 1 GiB. The minimum
                                  size is 1 GB, below that the database will
                                  not start.  [default: 2 GiB]

  --db-disk-size TEXT             The disk size available for the database.
                                  Format <number> <unit>, e.g. 1 GiB. The
                                  minimum size is 100 MiB. However, the setup
                                  creates volume files with at least 2 GB
                                  larger size, because the database needs at
                                  least so much more disk.  [default: 2 GiB]

  --nameserver TEXT               Add a nameserver to the list of DNS
                                  nameservers which the docker-db should use
                                  for resolving domain names. You can repeat
                                  this option to add further nameservers.

  --docker-runtime TEXT           The docker runtime used to start all
                                  containers

  --docker-db-image-version TEXT  Docker DB Image Version against which the
                                  tests should run.  [default: 8.31.0]

  --docker-db-image-name TEXT     Docker DB Image Name against which the tests
                                  should run.  [default: exasol/docker-db]

  --db-os-access METHOD           How to access file system and command
                                  line of the database operating
                                  system. Experimental option, will show no
                                  effect until implementation of feature
                                  SSH access is completed. [default:
                                  DOCKER_EXEC]

  --output-directory DIRECTORY    Output directory where the system stores all
                                  output and log files.  [default:
                                  .build_output]

  --temporary-base-directory DIRECTORY
                                  Directory where the system creates temporary
                                  directories.  [default: /tmp]

You can look at them on the commandline with:

./start-test-env spawn-test-environment --help

The integration-test-docker-environment command line tool#

Besides, the already mentioned command spawn-test-environment, the integration-test-docker-environemnt command line tool provides a couple of other helpful tools.

Run main.py --help, to get a list of the available commands:

Usage: main.py [OPTIONS] COMMAND [ARGS]...

Options:
  --help  Show this message and exit.

Commands:
  health                  Check the health of the execution environment.
  spawn-test-environment  This command spawn a test environment with a...

To get more details on a specific command run main.py <command> --help, e.g. main.py health --help:

Usage: main.py health [OPTIONS]

  Check the health of the execution environment.

  If no issues have been found, using the library or executing the test should
  work just fine. For all found issues there will be a proposed fix/solution.

  If the environment was found to be healthy the exit code will be 0.

Options:
  --help  Show this message and exit.

The integration-test-docker-environment API#

t.b.d. Link to sphinx documentation

Default Credentials#

The default credentials for the database are

User: sys
Password: exasol

and for the Bucket-FS:

User: w
Password: write

User: r
Password: read

Accessing the Environment Information#

The python setup script creates configuration files on the host and in the test container.

On the host the container information get stored in the build output directory usually under .build_output/cache/<ITDE_NAME>/*. In the test container the config file is stored at the root directory /.

The following config files are available:

environment_info.sh: This file is meant to be source by the bash and then provides the information as environment variables. Here an example for the content:

export ITDE_NAME=test
export ITDE_TYPE=EnvironmentType.docker_db

# Database IP in environment docker network
export ITDE_DATABASE_HOST=172.21.0.2
export ITDE_DATABASE_DB_PORT=8563
export ITDE_DATABASE_BUCKETFS_PORT=2580
export ITDE_DATABASE_SSH_PORT=22
export ITDE_DATABASE_CONTAINER_NAME=db_container_test
export ITDE_DATABASE_CONTAINER_NETWORK_ALIASES="exasol_test_database db_container_test"
# Database IP in the environment docker network
export ITDE_DATABASE_CONTAINER_IP_ADDRESS=172.21.0.2
export ITDE_DATABASE_CONTAINER_VOLUMNE_NAME=db_container_test_volume
# Database IP on the docker default bridge which under Linux available from the host
export ITDE_DATABASE_CONTAINER_DEFAULT_BRIDGE_IP_ADDRESS=172.17.0.3

export ITDE_TEST_CONTAINER_NAME=test_container_test
export ITDE_TEST_CONTAINER_NETWORK_ALIASES="test_container test_container_test"
# Test Container IP in the environment docker network
export ITDE_TEST_CONTAINER_IP_ADDRESS=172.21.0.3

environment_info.json: Contains the EnvironmentInfo objects pickled with JsonPickle

Currently supported Exasol Versions#

7.1: up to 7.1.29
8: from 8.17.0 up to 8.31.0

If you need further versions, please open an issue.

SSH Access#

Up to version 1.6.0 ITDE used docker_exec to access the operating system of the Exasol database inside the Docker Container, e.g. to analyze the content of logfiles or execute some shell commands. With version 8 of Exasol database the format of the Docker Containers might change so that docker_exec is no longer possible. Instead ITDE will then need to use SSH access.

You can select the access method with command line option --db-os-access. The default value is DOCKER_EXEC.

ITDE will create a random SSH key pair and store it to the file ~/.cache/exasol/itde/id_rsa with access permissions limited to the current user only. By this ITDE enables to reuse the same SSH keys for future sessions which leaves the container unchanged and hence reusable.

The public key will be added as file /root/.ssh/authorized_keys inside the Docker Container to enable SSH access with public key authentication.

You can use command line option --ssh-port-forward to specify a port on your host machine to which ITDE forwards the SSH port of the Docker Container running the Exasol database. If you do not specify a port then ITDE will select a random free port.

Tested Docker Runtimes#

Docker Default Runtime
NVIDIA Container Runtime for GPU accelerated UDFs

Mac OS X Support#

What do I need to do to start the Test Environment with Mac OS X#

The Exasol Docker-DB needs per default a bit more than 2 GB of RAM, however the Docker VM on Mac OS X provides often not enough RAM to accommodate this. You should increase the RAM of the Docker VM to at least 4.25 GB or reduce the DB Mem Size for the Exasol Docker-DB to less than 2 GB with --db-mem-size 1 GiB.

What happens under the hood#

Mac OS X with Docker Desktop for Mac uses a lightweight virtual machine with linux in which the docker daemon runs and the containers get started. This makes networking and shared directories more complicated then on Linux.

We start the python setup script for the test environment in its own Docker container, lets call it docker runner, because the library Luigi can have problems with Mac OS X and to avoid the installation of further dependencies. To support Mac OS X, the start-test-env script starts the docker runner container and mounts the docker socket at /var/run/docker.sock and the directory of the test environment from the Mac OS X host to the container. Then, it starts start-test-env-without-docker which then starts the python script. It is important, that the repository gets cloned to the Mac OS X host and not to a docker container, because the python scripts tries to start further docker container which use host mounts to share the tests directory of the test environment with the docker container.