Cannot migration from old 3.4.2 keycloak to latest version - migration

Question

I'm in charge of the migration of an old keycloak ( 3.4.2 ) to the latest version. I already migrated the database and the template.
The last thing that poses problem is custom providers for Account and Login.
I have two custom providers that extends :
FreeMarkerAccountProviderFactory
FreeMarkerLoginProviderFactory
At first, no providers was loaded at the starting of keycloak in version > 4.x. I investigate, and i found that override the default getId() method to return a value other than the default "freemarker" makes keycloak load them again.
But after that if i try to access the login page, i got a nullpointer exception on org.keycloak.services.resources.account.AccountFormService.init(AccountFormService.java:139)
Any idea ?
Edit : spi in provider are declared in META-INF/services and provider in standalone.xml
Edit 2 : I share the loginFormProvider as it as the same problem, trigger the same error but it less complicated in it's implementation
public class KeycloakFreeMarkerLoginFormsProvider extends FreeMarkerLoginFormProvider {
public KeycloakFreeMarkerLoginFormsProvider(KeycloakSession session, FreeMarkerUtil freeMarker) {
super(sesssion, freeMarker);
}
public Response createResponse(LoginFormsPages page) {
List<Foo> foo = // loading foo entities
List<Bar> bar = // loading bar entities
super.attributes.put("foo", foo);
super.attributes.put("bar", bar);
return super.createResponse(page);
}
}
public class KeycloakFreeMarkerLoginProviderFactory extends FreeMarkerLoginFormsProviderFactory {
private FreeMarkerUtil freeMarker;
public KeycloakFreeMarkerLoginProviderFactory() {
super();
}
#Override
public LoginFormsProvider create(KeycloakSession session) {
return new KeycloakFreeMarkerLoginFormsProvider(session, this.freeMarker);
}
#Override
public void init(Config.Scope config) {
this.freeMarker = new FreeMarkerUtil();
}
#Override
public void close() {
this.freeMarker = null;
}
/* Without getId() or with a value at freeMarker, the provider
is not load. With other value, get NPE */
#Override
public String getId() {
return "custom.provider";
}
}

Answer 1

Based on the comments chain, it appears that the problem is that the provider is not getting picked up by Keycloak. You have a couple of options for bundling a custom provider with Keycloak: as a module, or as a deployed war/ear/jar in the deployments directory.
Here's how to do it as a module:
You'll need to add some configuration (module.xml), and your jar, to the modules directory structure. It should look like something like this:
(keycloak root)
|- modules
|- system
|- layers
|- keycloak
|- com
|- yourcompany
|- yourmodule
|- main
|- your-module-name.jar
|- module.xml (see below)
Your module.xml should look something like this:
<?xml version="1.0" encoding="UTF-8"?>
<module name="com.yourcompany.yourmodule" xmlns="urn:jboss:module:1.6">
<resources>
<resource-root path="your-module-name.jar"/>
</resources>
<dependencies>
<!-- whatever module dependencies you need go here -->
<!-- these are just an example; you may or may not need them -->
<module name="org.jboss.logging" />
<module name="org.keycloak.keycloak-core"/>
<module name="org.keycloak.keycloak-services"/>
<module name="org.keycloak.keycloak-server-spi"/>
<module name="org.keycloak.keycloak-server-spi-private"/>
</dependencies>
</module>
Additionally, you'll need to configure standalone.xml and/or possibly standalone-ha.xml depending on your scenario (The default Keycloak Docker image uses -ha.xml by default). The pertinent section should look something like this:
<subsystem xmlns="urn:jboss:domain:keycloak-server:1.1">
<web-context>auth</web-context>
<providers>
<provider>
classpath:${jboss.home.dir}/providers/*
</provider>
<!-- add this -->
<provider>
module:com.yourcompany.yourmodule
</provider>
<!-- end add -->
</providers>
<master-realm-name>master</master-realm-name>
<scheduled-task-interval>900</scheduled-task-interval>
...
</subsystem>
Lastly, like you mention, you'll need the correct config in your META-INF/services directory: a file with the fully qualified classname of the ProviderFactory as defined by the SPI, with one line containing the fully qualified classname of your implementation. In your case, the file should be called org.keycloak.forms.login.LoginFormsProviderFactory and its value should be one line: (com.yourpackage).KeycloakFreeMarkerLoginProviderFactory
If it's picked up, you should be able to see it listed in the providers config in the admin UI. To view, log in to the admin console, click on your username in the upper right, and select "Server Info", then click on the "Providers" tab. You should see your provider listed under "login".