001/*
002 * Copyright © 2025 CUI-OpenSource-Software (info@cuioss.de)
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *     http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016package de.cuioss.benchmarking.common.token;
017
018/**
019 * Common interface for providing JWT tokens for benchmark testing.
020 * <p>
021 * This interface abstracts the token provisioning mechanism, allowing for different
022 * implementations depending on the benchmark requirements:
023 * <ul>
024 *   <li>{@code MockTokenRepository} - Generates tokens in-memory for isolated library benchmarks</li>
025 *   <li>{@code KeycloakTokenRepository} - Fetches real tokens from Keycloak for integration benchmarks</li>
026 * </ul>
027 * <p>
028 * Implementations should provide efficient token rotation to simulate realistic usage patterns
029 * and ensure proper cache miss scenarios during benchmarking.
030 * </p>
031 *
032 * @author Oliver Wolff
033 */
034public interface TokenProvider {
035
036    /**
037     * Gets the next token from the provider.
038     * <p>
039     * Implementations should provide round-robin or similar rotation strategy
040     * to ensure even distribution of tokens and realistic cache behavior.
041     * </p>
042     *
043     * @return a valid JWT access token
044     * @throws RuntimeException if a token cannot be provided
045     */
046    String getNextToken();
047
048    /**
049     * Returns the current size of the token pool.
050     * <p>
051     * This method is useful for monitoring and capacity planning during benchmarks.
052     * </p>
053     *
054     * @return the number of tokens currently available in the pool
055     */
056    int getTokenPoolSize();
057
058    /**
059     * Refreshes the token pool with new tokens.
060     * <p>
061     * This method allows for token renewal during long-running benchmarks.
062     * Implementations may choose to:
063     * <ul>
064     *   <li>Generate new tokens (mock implementations)</li>
065     *   <li>Fetch fresh tokens from authentication server (real implementations)</li>
066     *   <li>Do nothing if token refresh is not supported</li>
067     * </ul>
068     *
069     * @throws RuntimeException if the refresh operation fails
070     */
071    void refreshTokens();
072}