OAuthHandler.java
/*
* Copyright (c) 2020, WSO2 Inc. (http://www.wso2.org) All Rights Reserved.
*
* WSO2 Inc. licenses this file to you 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
*
* http://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.apache.synapse.endpoints.oauth;
import org.apache.synapse.MessageContext;
import org.apache.synapse.core.axis2.Axis2MessageContext;
import java.io.IOException;
import java.util.Map;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutionException;
/**
* This abstract class is to be used by OAuth handlers
* This class checks validity of tokens, request for tokens
* and add tokens to in-memory cache
*/
public abstract class OAuthHandler {
private final String id;
private final String tokenApiUrl;
protected OAuthHandler(String tokenApiUrl) {
this.id = OAuthUtils.getRandomOAuthHandlerID();
this.tokenApiUrl = tokenApiUrl;
}
/**
* This method will set the Authorization header after checking for expired tokens and generating new access
* tokens
*
* @param messageContext Message context to which the token needs to be set
* @throws OAuthException In the event of errors when generating new token
*/
public void setOAuthHeader(MessageContext messageContext) throws OAuthException {
setAuthorizationHeader(messageContext, getToken());
}
/**
* This method returns a token string
*
* @return token String
* @throws OAuthException In the event of errors when generating new token
*/
private String getToken() throws OAuthException {
try {
return TokenCache.getInstance().getToken(id, new Callable<String>() {
@Override
public String call() throws OAuthException, IOException {
return OAuthClient.generateToken(tokenApiUrl, buildTokenRequestPayload(), getEncodedCredentials());
}
});
} catch (ExecutionException e) {
throw new OAuthException(e);
}
}
/**
* Method to set the Authorization header
*
* @param messageContext Message Context of the request
* @param accessToken Access token to be set
*/
private void setAuthorizationHeader(MessageContext messageContext, String accessToken) {
Map<String, Object> transportHeaders = (Map<String, Object>) ((Axis2MessageContext) messageContext)
.getAxis2MessageContext().getProperty(org.apache.axis2.context.MessageContext.TRANSPORT_HEADERS);
transportHeaders.put(OAuthConstants.AUTHORIZATION_HEADER, OAuthConstants.BEARER + accessToken);
}
/**
* Method to remove the token from the cache when the endpoint is destroyed
*/
public void removeTokenFromCache() {
TokenCache.getInstance().removeToken(id);
}
/**
* Return the token server url relevant to the OAuth handler.
*
* @return String Token server url
*/
public String getTokenUrl() {
return tokenApiUrl;
}
/**
* Return the request payload relevant to the OAuth handler.
*
* @return String payload
*/
protected abstract String buildTokenRequestPayload();
/**
* Return the base 64 encoded clientId:clientSecret relevant to the OAuth handler.
*
* @return String payload
*/
protected abstract String getEncodedCredentials();
}