Fix data migration tables.d marker

[sklarsa]

Instead of checking for tables.d.0, we should check for the existence of tables.d.* as evidence that we are inside the db directory as part of the migration to v1.x.x.

[sklarsa]

@nwoolmer here's a test script to validate:

#!/bin/bash

set -e

# Set up test cluster
kind create cluster -n qdbtest

# Install last previous version
helm upgrade --install questdb questdb/questdb --version 0.42.1

echo "TEST SCRIPT: Waiting for deployment to finish (could take a minute or two depending on download speeds, be patient)"
sleep 10
kubectl wait --for=condition=Ready pod/questdb-0 --timeout=120s

# Sanity check to check the pod contents
kubectl exec -it questdb-0 -- ls -lah /var/lib/questdb


# Confirm contents of persistent volume claim
# Root of the volume should map to /var/lib/questdb/db
PV_PATH=$(kubectl get pv -o json | jq -r '.items[0].spec.hostPath.path')
echo "TEST SCRIPT: PV path on node: $PV_PATH"
echo "TEST SCRIPT: (Pre Migration) Contents of $PV_PATH"
docker exec qdbtest-control-plane ls -lah $PV_PATH

# Check out the new branch to install the patched version
git checkout steve/fix-data-migration-script
helm upgrade --install questdb ./charts/questdb

echo "TEST SCRIPT: Waiting for deployment to finish"
sleep 10
kubectl wait --for=condition=Ready pod/questdb-0 --timeout=60s

# Sanity check to check the pod contents
echo "TEST SCRIPT: (Post Migration) contents of /var/lib/questdb inside container"
kubectl exec -it questdb-0 -- ls -lah /var/lib/questdb

# Now confirm that the contents of the pvc map to the database root dir
echo "TEST SCRIPT: (Post Migration) contents of $PV_PATH"
docker exec qdbtest-control-plane ls -lah $PV_PATH

# Check init script logs
echo "TEST SCRIPT: init container logs"
kubectl logs questdb-0 -c init-db-migration

echo "TEST SCRIPT: scaling down and up to ensure that migration does not run again"

# Scale down the statefulset
kubectl scale statefulset questdb --replicas=0
sleep 1

# Scale up the statefulset
kubectl scale statefulset questdb --replicas=1
sleep 5

# Wait for the pod to be ready again
kubectl wait --for=condition=Ready pod/questdb-0 --timeout=30s

# Check init script logs
echo "TEST SCRIPT: init container logs"
kubectl logs questdb-0 -c init-db-migration

# Clean up
kind delete cluster -n qdbtest