Multitenant support

[bharatnpti]

I want to add support of multitenant in different modules. I would like to start with Rest Clients (@RegisterRestClient).

The config would be in below structure where a single client can have different configurations for different tenants.

quarkus.rest-client.firstRestClient.tenant1.url=https://quarkus-tenant1-firstrestclient.free.beeceptor.com
quarkus.rest-client.firstRestClient.tenant2.url=https://quarkus-tenant2-firstrestclient.free.beeceptor.com

Code approach -

resteasy-classic contains rest-client and rest-client-config.

Introduce new module rest-client-multiteant-config which contains the config class to read the properties/yaml as shown above.

However, presently rest-client and rest-client-config are tightly coupled as rest-client directly uses RestClientsConfig class from rest-client-config.

I propose to have a module containing only the abstraction and adding it as a dependency to rest-client-internal.
Then we can have separate modules :-

1. rest-client which has rest-client-internal and rest-client-config as dependency for supporting non-multitenant use case
2. rest-client-multitenant which has rest-client-internal and rest-client-multitenant-config as dependencies to support multitenant support.

[bharatnpti]

@TomasHofman - can you please provide inputs

[TomasHofman]

Hello @bharatnpti , can you describe more what / who is a "tenant" in the use case you have in mind?

[bharatnpti]

Hi @TomasHofman,

Below scenario demonstrates the meaning of tenant :-

Organization A - This org has a microservice(let's call it aggregator microservice) which fetches data from different clients/organization. The format of data,request, reponse etc is same. What differs is the base url on which these different clients exposes the api for retrieving the data.

Tenat 1 - Organization 1 - url - http://abc.com/data/
Tenat 2 - Organization 2 - url - http://xyz.com/data/

Now the aggregator microservice uses the @RegisterRestClient to make call to Organization 1 and Organization 2 api.

Presently, there is no way to specify different url for same @RegisterRestClient interface.

I would like to add the capability to RestClient to have different url configured in yml/properties for different tenant

[bharatnpti]

you mean extend the base interface for each tenant ?
I think approach suggested by @jamezp #29806 (reply in thread) will be much better if user of Quarkus has to do it.

However, I am proposing to add the capability in Quarkus itself.

Approach - rest-client will always the existing RestClientConfig object to build RestClient, however there will be separate modules for rest-client-config for multitenant and non-multitenant use cases which which will resolve and return RestClientConfig.

1. Decouple rest-client and rest-client-config modules by introducing abstraction.

rest-client-config-core (abstraction - contains only interface)
rest-client-config - implements rest-client-config-core and provides existing functionality
rest-client-config-multitenant - implements rest-client-config-core, reads the config in multi-tenant env and return the RestClientConfig instance (basically changing the structure of RestClientsConfig to have Map<String, Map<String, RestClientConfig> instead of Map<String, RestClientConfig>)

existing -
Map<String, RestClientConfig> is map of rest client name and corresponding configuration (RestClientConfig)

new -
Map<String, Map<String, RestClientConfig>> will be map of rest client name and value will be map of tenant and corresponding config (RestClientConfig)

Multitenant config :-

quarkus.rest-client.myRemoteService.tenant1.url=
quarkus.rest-client.myRemoteService.tenant1.connectTimeout=

quarkus.rest-client.myRemoteService.tenant2.url=
quarkus.rest-client.myRemoteService.tenant2.connectTimeout=

rest-client-core - has core functionality (as present) but use rest-client-config-core as dependency instead of rest-client-config

2. rest-client - has rest-client-config and rest-client-core as dependency - supporting the existing functionality
3. rest-client-multitenant - has rest-client-config-multitenant and rest-client-core as dependency - supporting the multitenant functionality

[geoand]

I think approach suggested by @jamezp #29806 (reply in thread) will be much better if user of Quarkus has to do it.

Sure, that's possible as well

[geoand]

I personally don't see much value, but if you want to try and do a PR, that's fine. Just keep in mind that the Reactive REST Client is the one we plan to support going forward

[bharatnpti]

sure, I'll give it a try.
Yes I am aware of future support, would like to start with classic rest client then reactive one

[bharatnpti]

Hi @geoand,

I have started working on it.
I am facing one issue while decoupling the rest-client-config and rest-client which is described here. Can you please help me with it or loop in someone who might be able to help Issue

[bharatnpti]

Hi @asoldano, @ronsigal - can you please provide inputs

[asoldano]

@jamezp ^