Feature flags for gradual rollouts

package com.example.demo.config;

import com.example.demo.feature.FeatureFlags;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.togglz.core.manager.EnumBasedFeatureProvider;
import org.togglz.core.spi.FeatureProvider;
import org.togglz.spring.security.SpringSecurityUserProvider;

@Configuration
public class TogglzConfig {

    @Bean
    public FeatureProvider featureProvider() {
        return new EnumBasedFeatureProvider(FeatureFlags.class);
    }

    @Bean
    public org.togglz.core.user.UserProvider userProvider() {
        return new SpringSecurityUserProvider("ROLE_ADMIN");
    }
}

package com.example.demo.service;

import com.example.demo.feature.FeatureFlags;
import org.springframework.stereotype.Service;

@Service
public class UserService {

    private final PaymentServiceV1 paymentV1;
    private final PaymentServiceV2 paymentV2;

    public UserService(PaymentServiceV1 paymentV1, PaymentServiceV2 paymentV2) {
        this.paymentV1 = paymentV1;
        this.paymentV2 = paymentV2;
    }

    public String getUserDashboard(Long userId) {
        if (FeatureFlags.NEW_USER_DASHBOARD.isActive()) {
            return generateNewDashboard(userId);
        } else {
            return generateOldDashboard(userId);
        }
    }

    public void processPayment(PaymentRequest request) {
        if (FeatureFlags.PAYMENT_V2.isActive()) {
            paymentV2.process(request);
        } else {
            paymentV1.process(request);
        }
    }

    public List<User> searchUsers(String query) {
        if (FeatureFlags.ADVANCED_SEARCH.isActive()) {
            return advancedSearch(query);
        } else {
            return basicSearch(query);
        }
    }

    private String generateNewDashboard(Long userId) {
        // New dashboard implementation
        return "new-dashboard";
    }

    private String generateOldDashboard(Long userId) {
        // Old dashboard implementation
        return "old-dashboard";
    }

    private List<User> advancedSearch(String query) {
        // Advanced search with filters, fuzzy matching
        return List.of();
    }

    private List<User> basicSearch(String query) {
        // Simple search
        return List.of();
    }
}

togglz:
  enabled: true
  console:
    enabled: true
    path: /togglz-console
    secured: true
  features:
    NEW_USER_DASHBOARD:
      enabled: true
    PAYMENT_V2:
      enabled: false
    ADVANCED_SEARCH:
      enabled: true
      strategy: gradual-rollout
      param:
        percentage: 20