Does Grails 4 supports both multi-datasource and multi-tenant?

Question

I have to implement the both techniques in grails 4:

1. Multi datasource
2. Multi tenant

Is it possible? if yes than how?

Answer 1

Yes, Grails 4 does support both, Multi-Datasources and Multi-Tenancy.

More specifically, Grails supports:

• Multiple Datasources since Grails 2.x
• Multiple Tenancy since Grails 3.2

Multi-Datasources

From the official documentation, here is how to do Multi-Datasources:

• In Grails 2
• In Grails 3
• In Grails 4

Multi-Tenancy

Multi-Tenancy is supported by GORM (the Grails' Object Relational Mapping) since GORM 6.0, introduced with Grails 3.2

From the official documentation, here is how to do Multi-Tenancy:

• Since Grails 3.2 / GORM 6.0
• Since Grails 3.3 / GORM 6.1
• Since Grails 4.0 / GORM 7.0

I have succesfully implemented Multi-Tenancy on two different Grails Projects. One of them was on a previously working application, and the adaptation was pretty straightforward using the DISCRIMINATOR approach.

Here a couple of tutorials on Multi-Tenancy with Grails, one using the DATABASE approach, and the other using the DISCRIMINATOR approach:

• Database per Tenant Multi-Tenancy
• Single Database Multi-Tenancy - Discriminator Column