Charm Testing reference

There are a lot of test types available and most of them are well applicable for Charmed PostgreSQL. Here is a list prepared by Canonical:

• Smoke test
• Unit tests
• Integration tests
• System test
• Performance test

Note: below examples are written for Juju 3.x, but Juju 2.9 is supported as well.
Please adopt the juju run ... commands as juju run-action ... --wait for Juju 2.9.

Smoke test

Complexity: trivial
Speed: fast
Goal: ensure basic functionality works over short amount of time.

Setup an Juju 3.x environment, deploy DB with test application and start “continuous write” test:

juju add-model smoke-test

juju deploy postgresql --channel 14/edge
juju add-unit postgresql -n 2 # (optional)

juju deploy postgresql-test-app
juju relate postgresql-test-app:first-database postgresql

# Start "continuous write" test:
juju run postgresql-test-app/leader start-continuous-writes
juju run postgresql/leader get-password

export user=operator
export pass=$(juju run postgresql/leader get-password username=${user} | yq '.. | select(. | has("password")).password')
export relname=first-database
export ip=$(juju show-unit postgresql/0 --endpoint database | yq '.. | select(. | has("public-address")).public-address')
export db=$(juju show-unit postgresql/0 --endpoint database | yq '.. | select(. | has("database")).database')
export relid=$(juju show-unit postgresql/0 --endpoint database | yq '.. | select(. | has("relation-id")).relation-id')
export query="select count(*) from continuous_writes"

watch -n1 -x juju run postgresql-test-app/leader run-sql dbname=${db} query="${query}" relation-id=${relid} relation-name=${relname}

# OR

watch -n1 -x juju ssh postgresql/leader "psql postgresql://${user}:${pass}@${ip}:5432/${db} -c \"${query}\""

# Watch the counter is growing!

Expected results:

• postgresql-test-app continuously inserts records into the database received in relation, the table continuous_writes.
• the counters (amount of records in table) are growing on all cluster members

Hints:

# Stop "continuous write" test
juju run postgresql-test-app/leader stop-continuous-writes

# Truncate "continuous write" table (delete all records from DB)
juju run postgresql-test-app/leader clear-continuous-writes

Unit tests

Please check the “Contributing” guide and follow tox run -e unit examples there.

Integration tests

Please check the “Contributing” guide and follow tox run -e integration examples there.

System test

Please check/deploy the charm postgresql-bundle (Git). It deploy and test all the necessary parts at once.

Performance test

Please check the separate document.