io.webfolder.cdp.session.SessionInvocationHandler.java Source code

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Here is the source code for io.webfolder.cdp.session.SessionInvocationHandler.java

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/**
 * The MIT License
 * Copyright  2017 WebFolder O
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
package io.webfolder.cdp.session;

import static java.lang.String.format;
import static java.util.Base64.getDecoder;
import static java.util.Collections.emptyMap;

import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Parameter;
import java.lang.reflect.Type;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.concurrent.atomic.AtomicInteger;

import com.google.gson.Gson;
import com.google.gson.JsonArray;
import com.google.gson.JsonElement;
import com.google.gson.JsonObject;
import com.neovisionaries.ws.client.WebSocket;

import io.webfolder.cdp.annotation.Domain;
import io.webfolder.cdp.annotation.Returns;
import io.webfolder.cdp.exception.CdpException;
import io.webfolder.cdp.logger.CdpLogger;

class SessionInvocationHandler implements InvocationHandler {

    private final Gson gson;

    private final WebSocket webSocket;

    private final AtomicInteger counter = new AtomicInteger(0);

    private final Map<Integer, WSContext> contextList;

    private final CdpLogger log;

    private final Session session;

    public SessionInvocationHandler(final Gson gson, final WebSocket webSocket,
            final Map<Integer, WSContext> contextList, final Session session, final CdpLogger log) {
        this.gson = gson;
        this.webSocket = webSocket;
        this.contextList = contextList;
        this.session = session;
        this.log = log;
    }

    @Override
    public Object invoke(final Object proxy, final Method method, final Object[] args) throws Throwable {

        if (!session.isConnected()) {
            log.error("Unable to invoke {}.{}()",
                    new Object[] { method.getDeclaringClass().getName(), method.getName() });
            throw new CdpException("WebSocket connection is not alive");
        }

        final Class<?> klass = method.getDeclaringClass();
        final String domain = klass.getAnnotation(Domain.class).value();
        final String command = method.getName();

        boolean hasArgs = args != null && args.length > 0;

        Map<String, Object> params = hasArgs ? new HashMap<>(args.length) : emptyMap();

        if (hasArgs) {
            int argIndex = 0;
            Parameter[] parameters = method.getParameters();
            for (Object argValue : args) {
                String argName = parameters[argIndex++].getName();
                params.put(argName, argValue);
            }
        }

        int id = counter.incrementAndGet();
        Map<String, Object> map = new HashMap<>(3);
        map.put("id", id);
        map.put("method", format("%s.%s", domain, command));
        map.put("params", params);

        String json = gson.toJson(map);

        log.debug(json);

        WSContext context = new WSContext();
        contextList.put(id, context);

        webSocket.sendText(json);
        context.await();

        if (context.getError() != null) {
            throw context.getError();
        }

        Class<?> retType = method.getReturnType();

        if (retType.equals(void.class) || retType.equals(Void.class)) {
            return null;
        }

        JsonElement data = context.getData();

        String returns = method.isAnnotationPresent(Returns.class) ? method.getAnnotation(Returns.class).value()
                : null;

        if (data == null) {
            return null;
        }

        if (!data.isJsonObject()) {
            throw new CdpException("invalid response");
        }

        JsonObject object = data.getAsJsonObject();
        JsonElement result = object.get("result");

        if (result == null || !result.isJsonObject()) {
            throw new CdpException("invalid result");
        }

        JsonObject resultObject = result.getAsJsonObject();

        Object ret = null;
        Type genericReturnType = method.getGenericReturnType();

        if (returns != null) {

            JsonElement jsonElement = resultObject.get(returns);

            if (jsonElement != null && jsonElement.isJsonPrimitive()) {
                if (String.class.equals(retType)) {
                    return resultObject.get(returns).getAsString();
                } else if (Boolean.class.equals(retType)) {
                    return resultObject.get(returns).getAsBoolean() ? Boolean.TRUE : Boolean.FALSE;
                } else if (Integer.class.equals(retType)) {
                    return new Integer(resultObject.get(returns).getAsInt());
                } else if (Double.class.equals(retType)) {
                    return new Double(resultObject.get(returns).getAsDouble());
                }
            }

            if (jsonElement != null && byte[].class.equals(genericReturnType)) {
                String encoded = gson.fromJson(jsonElement, String.class);
                if (encoded == null || encoded.trim().isEmpty()) {
                    return null;
                } else {
                    return getDecoder().decode(encoded);
                }
            }

            if (List.class.equals(retType)) {
                JsonArray jsonArray = jsonElement.getAsJsonArray();
                ret = gson.fromJson(jsonArray, genericReturnType);
            } else {
                ret = gson.fromJson(jsonElement, genericReturnType);
            }
        } else {
            ret = gson.fromJson(resultObject, genericReturnType);
        }

        return ret;
    }

    void dispose() {
        for (WSContext context : contextList.values()) {
            try {
                context.setData(null);
            } catch (Throwable t) {
            }
        }
    }
}