public void deriveFromSchemas(DeployState deployState) {
        for (SchemaInfo spec : schemas().values()) {
            if (spec.fullSchema() instanceof DocumentOnlySchema) continue; // TODO verify if this special handling is necessary
            String schemaName = spec.fullSchema().getName();
            var derived = new DerivedConfiguration(deployState, spec.fullSchema(), spec.getIndexMode());
            documentDbs.put(schemaName, new DocumentDatabase(this, schemaName, derived));
            if (spec.getIndexMode() == SchemaInfo.IndexMode.STREAMING) {
                var parent = (TreeConfigProducer<AnyConfigProducer>)getParent();
                documentDBProducerForStreaming.put(schemaName, new AttributesProducer(parent, schemaName, derived));
            }
        }
    }
Must be called after cluster is built, to derive schema configs.
Derives the schemas from the application package.
Also stores the document names contained in the schemas.
config-model/src/main/java/com/yahoo/vespa/model/search/SearchCluster.java