/*
* Copyright 2017 JBoss Inc
*
* 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.
*/
package io.apiman.gateway.engine.vertx.polling;
import io.apiman.gateway.engine.IEngineConfig;
import io.apiman.gateway.engine.async.AsyncInitialize;
import io.apiman.gateway.engine.async.AsyncResultImpl;
import io.apiman.gateway.engine.async.IAsyncHandler;
import io.apiman.gateway.engine.async.IAsyncResultHandler;
import io.apiman.gateway.engine.beans.Api;
import io.apiman.gateway.engine.beans.Client;
import io.apiman.gateway.engine.impl.InMemoryRegistry;
import io.apiman.gateway.engine.vertx.polling.exceptions.UnsupportedProtocolException;
import io.apiman.gateway.engine.vertx.polling.fetchers.AccessTokenResourceFetcher;
import io.apiman.gateway.engine.vertx.polling.fetchers.FileResourceFetcher;
import io.apiman.gateway.engine.vertx.polling.fetchers.HttpResourceFetcher;
import io.apiman.gateway.engine.vertx.polling.fetchers.ResourceFetcher;
import io.apiman.gateway.platforms.vertx3.common.verticles.Json;
import io.vertx.core.Vertx;
import io.vertx.core.buffer.Buffer;
import io.vertx.core.impl.Arguments;
import io.vertx.core.json.DecodeException;
import io.vertx.core.json.JsonArray;
import io.vertx.core.json.JsonObject;
import io.vertx.core.logging.Logger;
import io.vertx.core.logging.LoggerFactory;
import java.net.URI;
import java.util.ArrayDeque;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Deque;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.Objects;
import java.util.concurrent.atomic.AtomicInteger;
import org.apache.commons.lang3.StringUtils;
/**
* URI loading registry that pulls configuration from a specified JSON file.
* <ul>
* <li>configUri: apiman policy config to load from JSON via file
* ({@link FileResourceFetcher}) or HTTP/S ({@link HttpResourceFetcher}).
* See the corresponding fetcher for additional options.</li>
* </ul>
*
* @author Marc Savy {@literal <marc@rhymewithgravy.com>}
* @see FileResourceFetcher
* @see HttpResourceFetcher
* @see AccessTokenResourceFetcher
*/
@SuppressWarnings("nls")
public class URILoadingRegistry extends InMemoryRegistry implements AsyncInitialize {
// Protected by DCL, use #getUriLoader
private static volatile OneShotURILoader instance;
private URI uri;
private Vertx vertx;
private Map<String, String> options;
public URILoadingRegistry(Vertx vertx, IEngineConfig vxConfig, Map<String, String> options) {
super();
this.vertx = vertx;
this.options = options;
Arguments.require(options.containsKey("configUri"), "configUri is required in configuration");
uri = URI.create(options.get("configUri"));
}
public URILoadingRegistry(Map<String, String> options) {
this(Vertx.vertx(), null, options);
}
@Override
public void initialize(IAsyncResultHandler<Void> resultHandler) {
getURILoader(vertx, uri, options).subscribe(this, resultHandler);
}
private static OneShotURILoader getURILoader(Vertx vertx, URI uri, Map<String, String> options) {
if (instance == null) {
synchronized(URILoadingRegistry.class) {
if (instance == null) {
instance = new OneShotURILoader(vertx, uri, options);
}
}
}
return instance;
}
// For testing only. Reloads rather than full restart.
public static void reloadData(IAsyncHandler<Void> doneHandler) {
synchronized(URILoadingRegistry.class) {
if (instance == null) {
doneHandler.handle((Void) null);
return;
}
Map<URILoadingRegistry, IAsyncResultHandler<Void>> regs = instance.handlers;
Vertx vertx = instance.vertx;
URI uri = instance.uri;
Map<String, String> config = instance.config;
AtomicInteger ctr = new AtomicInteger(regs.size());
OneShotURILoader newLoader = new OneShotURILoader(vertx, uri, config);
regs.entrySet().stream().forEach(pair -> {
// Clear the registrys' internal maps to prepare for reload.
// NB: If we add production hot reloading, we'll need to work around this (e.g. clone?).
pair.getKey().getMap().clear();
// Re-subscribe the registry.
newLoader.subscribe(pair.getKey(), result -> {
checkAndFlip(ctr.decrementAndGet(), newLoader, doneHandler);
});
});
checkAndFlip(ctr.get(), newLoader, doneHandler);
}
}
private static void checkAndFlip(int ctr, OneShotURILoader instance, IAsyncHandler<Void> doneHandler) {
if (ctr == 0) {
doneHandler.handle((Void) null);
URILoadingRegistry.instance = instance;
}
}
public static void reset() {
synchronized(URILoadingRegistry.class) {
instance = null;
}
}
@Override
public void publishApi(Api api, IAsyncResultHandler<Void> handler) {
throw new UnsupportedOperationException();
}
@Override
public void retireApi(Api api, IAsyncResultHandler<Void> handler) {
throw new UnsupportedOperationException();
}
@Override
public void registerClient(Client client, IAsyncResultHandler<Void> handler) {
throw new UnsupportedOperationException();
}
@Override
public void unregisterClient(Client client, IAsyncResultHandler<Void> handler) {
throw new UnsupportedOperationException();
}
protected void publishApiInternal(Api api, IAsyncResultHandler<Void> handler) {
super.publishApi(api, handler);
}
protected void registerClientInternal(Client client, IAsyncResultHandler<Void> handler) {
super.registerClient(client, handler);
}
private static final class OneShotURILoader {
Vertx vertx;
URI uri;
Map<String, String> config;
Map<URILoadingRegistry, IAsyncResultHandler<Void>> handlers = new LinkedHashMap<>();
private Deque<URILoadingRegistry> awaiting = new ArrayDeque<>();
private List<URILoadingRegistry> allRegistries = new ArrayList<>();
private Buffer rawData;
private boolean dataProcessed = false;
private List<Client> clients = Collections.emptyList();
private List<Api> apis = Collections.emptyList();
private Logger log = LoggerFactory.getLogger(OneShotURILoader.class);
private IAsyncHandler<Void> reloadHandler;
private boolean failed;
public OneShotURILoader(Vertx vertx, URI uri, Map<String, String> config) {
this.config = config;
this.vertx = vertx;
this.uri = uri;
fetchResource();
}
private void fetchResource() {
getResourceFetcher()
.exceptionHandler(this::failAll)
.fetch(data -> {
rawData = data;
processData();
});
}
private ResourceFetcher getResourceFetcher() {
String scheme = uri.getScheme() == null ? "file" : uri.getScheme().toLowerCase();
switch (scheme) {
case "http":
return new HttpResourceFetcher(vertx, uri, config, false);
case "https":
return new HttpResourceFetcher(vertx, uri, config, true);
case "file":
return new FileResourceFetcher(vertx, uri, config);
default:
throw new UnsupportedProtocolException(String.format("%s is not supported. Available: http, https and file.", uri.getScheme()));
}
}
private void processData() {
if (rawData.length() == 0) {
log.warn("File loaded into registry was empty. No entities created.");
dataProcessed = true;
allRegistries.stream().forEach(this::checkSuccess);
return;
}
try {
JsonObject json = new JsonObject(rawData.toString("UTF-8").trim());
log.trace("Processing JSON: {0}", json);
clients = requireJsonArray("clients", json, Client.class);
apis = requireJsonArray("apis", json, Api.class);
dataProcessed = true;
checkQueue();
} catch (DecodeException e) {
failAll(e);
}
}
@SuppressWarnings("unchecked")
private <T, K> List<T> requireJsonArray(String keyName, JsonObject json, Class<K> klazz) {
// Contains key.
Arguments.require(json.containsKey(keyName),
String.format("Must provide array of %s objects for key '%s'", StringUtils.capitalize(keyName), keyName));
// Is of type array.
Arguments.require(json.getValue(keyName) instanceof JsonArray,
String.format("'%s' must be a Json array", keyName));
// Transform into List<T>.
return Json.decodeValue(json.getJsonArray(keyName).encode(), List.class, klazz);
}
public void subscribe(URILoadingRegistry registry, IAsyncResultHandler<Void> handler) {
synchronized (URILoadingRegistry.class) {
Objects.requireNonNull(registry, "registry must be non-null.");
Objects.requireNonNull(handler, "handler must be non-null.");
handlers.put(registry, handler);
allRegistries.add(registry);
awaiting.add(registry);
vertx.runOnContext(action -> checkQueue());
}
}
private void checkQueue() {
if (dataProcessed && awaiting.size()>0) {
loadDataIntoRegistries();
}
}
private void loadDataIntoRegistries() {
URILoadingRegistry reg = null;
while ((reg = awaiting.poll()) != null) {
log.debug("Loading data into registry {0}:", reg);
for (Api api : apis) {
reg.publishApiInternal(api, handleAnyFailure());
log.debug("Publishing: {0} ", api);
}
for (Client client : clients) {
reg.registerClientInternal(client, handleAnyFailure());
log.debug("Registering: {0} ", client);
}
checkSuccess(reg);
}
if (reloadHandler != null)
reloadHandler.handle((Void) null);
}
private IAsyncResultHandler<Void> handleAnyFailure() {
return result -> {
if (result.isError()) {
log.error(result.getError());
failAll(result.getError());
}
};
}
private void failAll(Throwable cause) {
failed = true;
AsyncResultImpl<Void> failure = AsyncResultImpl.create(cause);
handlers.values().stream().forEach(failureHandler -> {
vertx.runOnContext(run -> failureHandler.handle(failure));
});
}
private void checkSuccess(URILoadingRegistry reg) {
if (!failed) {
handlers.get(reg).handle(AsyncResultImpl.create((Void) null));
}
}
}
}