org.springframework.security.core.token.TokenService Maven / Gradle / Ivy
/*
* Copyright 2002-2016 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.security.core.token;
/**
* Provides a mechanism to allocate and rebuild secure, randomised tokens.
*
*
* Implementations are solely concern with issuing a new {@link Token} on demand. The
* issued Token may contain user-specified extended information. The token
* also contains a cryptographically strong, byte array-based key. This permits the token
* to be used to identify a user session, if desired. The key can subsequently be
* re-presented to the TokenService for verification and reconstruction of a
* Token equal to the original Token.
*
*
*
* Given the tightly-focused behaviour provided by this interface, it can serve as a
* building block for more sophisticated token-based solutions. For example,
* authentication systems that depend on stateless session keys. These could, for
* instance, place the username inside the user-specified extended information associated
* with the key). It is important to recognise that we do not intend for this interface to
* be expanded to provide such capabilities directly.
*
*
* @author Ben Alex
* @since 2.0.1
*
*/
public interface TokenService {
/**
* Forces the allocation of a new {@link Token}.
* @param extendedInformation the extended information desired in the token (cannot be
* null, but can be empty)
* @return a new token that has not been issued previously, and is guaranteed to be
* recognised by this implementation's {@link #verifyToken(String)} at any future
* time.
*/
Token allocateToken(String extendedInformation);
/**
* Permits verification the {@link Token#getKey()} was issued by this
* TokenService and reconstructs the corresponding Token.
* @param key as obtained from {@link Token#getKey()} and created by this
* implementation
* @return the token, or null if the token was not issued by this
* TokenService
*/
Token verifyToken(String key);
}