OAuthUtils.java

/**
 * Copyright © 2015 Instituto Superior Técnico
 *
 * This file is part of Bennu OAuth.
 *
 * Bennu OAuth is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Bennu OAuth is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with Bennu OAuth.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.fenixedu.bennu.oauth.util;

import java.nio.charset.StandardCharsets;
import java.util.Base64;
import java.util.Optional;
import java.util.UUID;

import org.fenixedu.bennu.oauth.OAuthProperties;
import org.fenixedu.bennu.oauth.domain.ApplicationUserSession;

import pt.ist.fenixframework.DomainObject;
import pt.ist.fenixframework.FenixFramework;

import com.google.common.base.Joiner;
import com.google.common.base.Strings;
import com.google.common.hash.Hashing;
import com.google.gson.JsonObject;

public class OAuthUtils {

    public final static String ACCESS_TOKEN = "access_token";
    public final static String REFRESH_TOKEN = "refresh_token";
    public final static String EXPIRES_IN = "expires_in";
    public final static String TOKEN_TYPE = "token_type";
    public final static String TOKEN_TYPE_HEADER_ACCESS_TOKEN = "Bearer";

    public static String generateCode() {
        return Hashing.sha512().hashString(UUID.randomUUID().toString(), StandardCharsets.UTF_8).toString();
    }

    public static String generateToken(DomainObject domainObject) {
        return generateToken(domainObject.getExternalId(), generateCode());
    }

    public static String generateToken(String id, String random) {
        return Base64.getEncoder().encodeToString(Joiner.on(":").join(id, random).getBytes(StandardCharsets.UTF_8))
                .replace("=", "").replace("+", "-").replace("/", "-");
    }

    public static JsonObject getJsonTokens(ApplicationUserSession appUserSession) {
        return getJsonTokens(appUserSession.getAccessToken(), appUserSession.getRefreshToken());
    }

    public static JsonObject getJsonTokens(String accessToken) {
        return getJsonTokens(accessToken, null, null, null);
    }

    public static JsonObject getJsonTokens(String accessToken, String refreshToken) {
        return getJsonTokens(accessToken, refreshToken, OAuthProperties.getConfiguration().getAccessTokenExpirationSeconds(),
                TOKEN_TYPE_HEADER_ACCESS_TOKEN);
    }

    public static JsonObject getJsonTokens(String accessToken, String refreshToken, Integer accessTokenExpirationSeconds,
            String tokenType) {
        JsonObject jsonResponse = new JsonObject();
        jsonResponse.addProperty(ACCESS_TOKEN, accessToken);
        if (!Strings.isNullOrEmpty(refreshToken)) {
            jsonResponse.addProperty(REFRESH_TOKEN, refreshToken);
        }
        if (accessTokenExpirationSeconds != null) {
            jsonResponse.addProperty(EXPIRES_IN, accessTokenExpirationSeconds);
        }
        if (!Strings.isNullOrEmpty(tokenType)) {
            jsonResponse.addProperty(TOKEN_TYPE, tokenType);
        }
        return jsonResponse;
    }

    public static final <T extends DomainObject> Optional<T> getDomainObject(final String externalId) {
        return getDomainObject(externalId, null);
    }

    public static final <T extends DomainObject> Optional<T> getDomainObject(final String externalId, final Class<T> clazz) {
        try {
            T domainObject = FenixFramework.getDomainObject(externalId);
            if (!FenixFramework.isDomainObjectValid(domainObject)
                    || (clazz != null && !clazz.isAssignableFrom(domainObject.getClass()))) {
                return Optional.empty();
            }
            return Optional.of(domainObject);
        } catch (Exception nfe) {
            return Optional.empty();
        }
    }
}