path: root/policy-endpoints/src/main/java/org/onap/policy/common/endpoints/http/server/internal/JettyJerseyServer.java

/*-
 * ============LICENSE_START=======================================================
 * policy-endpoints
 * ================================================================================
 * Copyright (C) 2017-2018 AT&T Intellectual Property. All rights reserved.
 * ================================================================================
 * 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
 * 
 *      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.
 * ============LICENSE_END=========================================================
 */

package org.onap.policy.common.endpoints.http.server.internal;

import java.util.HashMap;

import org.eclipse.jetty.servlet.ServletHolder;
import org.onap.policy.common.utils.network.NetworkUtil;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import io.swagger.jersey.config.JerseyJaxrsConfig;

/**
 * REST Jetty Server that uses Jersey Servlets to support JAX-RS Web Services
 */
public class JettyJerseyServer extends JettyServletServer {

    /**
     * Swagger API Base Path
     */
    protected static final String SWAGGER_API_BASEPATH = "swagger.api.basepath";

    /**
     * Swagger Context ID
     */
    protected static final String SWAGGER_CONTEXT_ID = "swagger.context.id";

    /**
     * Swagger Scanner ID
     */
    protected static final String SWAGGER_SCANNER_ID = "swagger.scanner.id";

    /**
     * Swagger Pretty Print
     */
    protected static final String SWAGGER_PRETTY_PRINT = "swagger.pretty.print";

    /**
     * Swagger Packages
     */
    protected static final String SWAGGER_INIT_PACKAGES_PARAM_VALUE = "io.swagger.jaxrs.listing";

    /**
     * Jersey Packages Init Param Name
     */
    protected static final String JERSEY_INIT_PACKAGES_PARAM_NAME = "jersey.config.server.provider.packages";

    /**
     * Jersey Packages Init Param Value
     */
    protected static final String JERSEY_INIT_PACKAGES_PARAM_VALUE = "com.fasterxml.jackson.jaxrs.json";

    /**
     * Jersey Classes Init Param Name
     */
    protected static final String JERSEY_INIT_CLASSNAMES_PARAM_NAME = "jersey.config.server.provider.classnames";

    /**
     * Jersey Jackson Classes Init Param Value
     */
    protected static final String JERSEY_JACKSON_INIT_CLASSNAMES_PARAM_VALUE =
            "com.fasterxml.jackson.jaxrs.json.JacksonJaxbJsonProvider";

    /**
     * Jersey Swagger Classes Init Param Value
     */
    protected static final String SWAGGER_INIT_CLASSNAMES_PARAM_VALUE =
            "io.swagger.jaxrs.listing.ApiListingResource," + "io.swagger.jaxrs.listing.SwaggerSerializers";
    /**
     * Logger
     */
    protected static Logger logger = LoggerFactory.getLogger(JettyJerseyServer.class);

    /**
     * Container for servlets
     */
    protected HashMap<String, ServletHolder> servlets = new HashMap<>();

    /**
     * Swagger ID
     */
    protected String swaggerId = null;

    /**
     * Constructor
     * 
     * @param name name
     * @param https enable https?
     * @param host host server host
     * @param port port server port
     * @param swagger support swagger?
     * @param contextPath context path
     * 
     * @throws IllegalArgumentException in invalid arguments are provided
     */
    public JettyJerseyServer(String name, boolean https, String host, int port, String contextPath, boolean swagger) {

        super(name, https, host, port, contextPath);
        if (swagger) {
            this.swaggerId = "swagger-" + this.port;
            attachSwaggerServlet(https);
        }
    }

    /**
     * attaches a swagger initialization servlet
     */
    protected void attachSwaggerServlet(boolean https) {

        ServletHolder swaggerServlet = context.addServlet(JerseyJaxrsConfig.class, "/");

        String hostname = this.connector.getHost();
        if (hostname == null || hostname.isEmpty() || hostname.equals(NetworkUtil.IPv4_WILDCARD_ADDRESS)) {
            hostname = NetworkUtil.getHostname();
        }

        swaggerServlet.setInitParameter(SWAGGER_API_BASEPATH,
                ((https) ? "https://" : "http://") + hostname + ":" + this.connector.getPort() + "/");
        swaggerServlet.setInitParameter(SWAGGER_CONTEXT_ID, swaggerId);
        swaggerServlet.setInitParameter(SWAGGER_SCANNER_ID, swaggerId);
        swaggerServlet.setInitParameter(SWAGGER_PRETTY_PRINT, "true");
        swaggerServlet.setInitOrder(2);

        if (logger.isDebugEnabled()) {
            logger.debug("{}: Swagger Servlet has been attached: {}", this, swaggerServlet.dump());
        }
    }

    /**
     * retrieves cached server based on servlet path
     * 
     * @param servletPath servlet path
     * @return the jetty servlet holder
     * 
     * @throws IllegalArgumentException if invalid arguments are provided
     */
    protected synchronized ServletHolder getServlet(String servletPath) {

        ServletHolder jerseyServlet = servlets.get(servletPath);
        if (jerseyServlet == null) {
            jerseyServlet = context.addServlet(org.glassfish.jersey.servlet.ServletContainer.class, servletPath);
            jerseyServlet.setInitOrder(0);
            servlets.put(servletPath, jerseyServlet);
        }

        return jerseyServlet;
    }

    @Override
    public synchronized void addServletPackage(String servletPath, String restPackage) {
        String servPath = servletPath;
        if (restPackage == null || restPackage.isEmpty()) {
            throw new IllegalArgumentException("No discoverable REST package provided");
        }

        if (servPath == null || servPath.isEmpty()) {
            servPath = "/*";
        }

        ServletHolder jerseyServlet = this.getServlet(servPath);

        String initClasses = jerseyServlet.getInitParameter(JERSEY_INIT_CLASSNAMES_PARAM_NAME);
        if (initClasses != null && !initClasses.isEmpty()) {
            logger.warn("Both packages and classes are used in Jetty+Jersey Configuration: {}", restPackage);
        }

        String initPackages = jerseyServlet.getInitParameter(JERSEY_INIT_PACKAGES_PARAM_NAME);
        if (initPackages == null) {
            if (this.swaggerId != null) {
                initPackages =
                        JERSEY_INIT_PACKAGES_PARAM_VALUE + "," + SWAGGER_INIT_PACKAGES_PARAM_VALUE + "," + restPackage;

                jerseyServlet.setInitParameter(SWAGGER_CONTEXT_ID, swaggerId);
                jerseyServlet.setInitParameter(SWAGGER_SCANNER_ID, swaggerId);
            } else {
                initPackages = JERSEY_INIT_PACKAGES_PARAM_VALUE + "," + restPackage;
            }
        } else {
            initPackages = initPackages + "," + restPackage;
        }

        jerseyServlet.setInitParameter(JERSEY_INIT_PACKAGES_PARAM_NAME, initPackages);

        if (logger.isDebugEnabled()) {
            logger.debug("{}: added REST package: {}", this, jerseyServlet.dump());
        }
    }

    @Override
    public synchronized void addServletClass(String servletPath, String restClass) {

        if (restClass == null || restClass.isEmpty()) {
            throw new IllegalArgumentException("No discoverable REST class provided");
        }

        if (servletPath == null || servletPath.isEmpty()) {
            servletPath = "/*";
        }

        ServletHolder jerseyServlet = this.getServlet(servletPath);

        String initPackages = jerseyServlet.getInitParameter(JERSEY_INIT_PACKAGES_PARAM_NAME);
        if (initPackages != null && !initPackages.isEmpty()) {
            logger.warn("Both classes and packages are used in Jetty+Jersey Configuration: {}", restClass);
        }

        String initClasses = jerseyServlet.getInitParameter(JERSEY_INIT_CLASSNAMES_PARAM_NAME);
        if (initClasses == null) {
            if (this.swaggerId != null) {
                initClasses = JERSEY_JACKSON_INIT_CLASSNAMES_PARAM_VALUE + "," + SWAGGER_INIT_CLASSNAMES_PARAM_VALUE
                        + "," + restClass;

                jerseyServlet.setInitParameter(SWAGGER_CONTEXT_ID, swaggerId);
                jerseyServlet.setInitParameter(SWAGGER_SCANNER_ID, swaggerId);
            } else {
                initClasses = JERSEY_JACKSON_INIT_CLASSNAMES_PARAM_VALUE + "," + restClass;
            }
        } else {
            initClasses = initClasses + "," + restClass;
        }

        jerseyServlet.setInitParameter(JERSEY_INIT_CLASSNAMES_PARAM_NAME, initClasses);

        if (logger.isDebugEnabled()) {
            logger.debug("{}: added REST class: {}", this, jerseyServlet.dump());
        }
    }

    @Override
    public String toString() {
        StringBuilder builder = new StringBuilder();
        builder.append("JettyJerseyServer [servlets=").append(servlets).append(", swaggerId=").append(swaggerId)
                .append(", toString()=").append(super.toString()).append("]");
        return builder.toString();
    }
}