Kubernetes init database in a dirty way

Sometimes you need a dirty trick initialized the kubernetes running database with a set of sql statements (ddls). Here you are a simple example.

init-db:

kubectl exec -i --namespace timescaledb svc/csdb -c timescaledb -- \

        psql -U postgres -d cas --file=- <ddls/00-init-database.sql;

init-db-tables:

@for f in $(shell ls ddls/$(FILE_PREFIX)*.sql | grep -v 00-init); do \

kubectl exec -i --namespace timescaledb svc/csdb -c timescaledb -- \

            psql -U postgres -d cas --file=- <$$f; \

done

But what if you would like to variables in your script.

Here's a solution:

bash -c "cat <<EOF

$(< ddls/00-init-database.sql_tpl)

EOF" | kubectl exec -i --tty --namespace timescaledb ${PGMASTERPOD} -c timescaledb -- \

    psql -U postgres -d ${DBNAME}