TL;DR
spring:
jpa:
generate-ddl: true
properties:
javax:
persistence:
schema-generation:
database:
action: drop-and-create
create-source: script-then-metadata
create-script-source: init.sql
init.sql
CREATE ALIAS IF NOT EXISTS H2GIS_SPATIAL FOR "org.h2gis.functions.factory.H2GISFunctions.load";
CALL H2GIS_SPATIAL();
CREATE DOMAIN POINT AS GEOMETRY(POINT);
CREATE DOMAIN POLYGON AS GEOMETRY(POLYGON);