io.macgyver.plugin.cloud.aws.event.SNSMacGyverEventWriter.java Source code

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Here is the source code for io.macgyver.plugin.cloud.aws.event.SNSMacGyverEventWriter.java

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/**
 * 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.macgyver.plugin.cloud.aws.event;

import java.util.Optional;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicReference;

import org.lendingclub.reflex.concurrent.ConcurrentSubscribers;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.boot.context.event.ApplicationReadyEvent;
import org.springframework.context.ApplicationListener;

import com.amazonaws.handlers.AsyncHandler;
import com.amazonaws.services.sns.AmazonSNSAsyncClient;
import com.amazonaws.services.sns.model.PublishRequest;
import com.amazonaws.services.sns.model.PublishResult;

import io.macgyver.core.event.EventSystem;
import io.macgyver.core.event.MacGyverMessage;
import io.reactivex.functions.Consumer;

public class SNSMacGyverEventWriter implements ApplicationListener<ApplicationReadyEvent> {

    AtomicReference<AmazonSNSAsyncClient> snsClientRef = new AtomicReference<>();
    AtomicReference<String> topicArnRef = new AtomicReference<>();
    Logger logger = LoggerFactory.getLogger(SNSMacGyverEventWriter.class);

    AtomicBoolean enabled = new AtomicBoolean(true);

    public void setSNSClient(AmazonSNSAsyncClient client) {
        withSNSClient(client);
    }

    public SNSMacGyverEventWriter withSNSClient(AmazonSNSAsyncClient client) {
        this.snsClientRef.set(client);
        return this;
    }

    public void setTopicArn(String arn) {
        withTopicArn(arn);
    }

    public SNSMacGyverEventWriter withTopicArn(String arn) {
        this.topicArnRef.set(arn);
        return this;
    }

    class ResponseHandler implements AsyncHandler<PublishRequest, PublishResult> {

        @Override
        public void onError(Exception exception) {
            logger.error("problem sending message to SNS", exception);

        }

        @Override
        public void onSuccess(PublishRequest request, PublishResult result) {
            // TODO Auto-generated method stub

        }

    }

    public boolean isEnabled() {
        return enabled.get() && getTopicArn().isPresent() && getSNSClient().isPresent();
    }

    public void setEnabled(boolean b) {
        enabled.set(b);
    }

    public Optional<AmazonSNSAsyncClient> getSNSClient() {
        return Optional.ofNullable(snsClientRef.get());
    }

    public Optional<String> getTopicArn() {
        return Optional.ofNullable(topicArnRef.get());
    }

    public void subscribe(EventSystem eventSystem) {

        Consumer consumer = new Consumer() {
            public void accept(Object event) {

                try {
                    if (isEnabled()) {
                        PublishRequest request = new PublishRequest();
                        request.setTopicArn(getTopicArn().get());
                        request.setMessage(MacGyverMessage.class.cast(event).getEnvelope().toString());
                        getSNSClient().get().publishAsync(request, new ResponseHandler());
                    }
                } catch (Exception e) {
                    logger.error("problem sending message to SNS: {}", e.toString());
                }
            }
        };
        ConcurrentSubscribers.createConcurrentSubscriber(eventSystem.createObservable(MacGyverMessage.class))
                .withNewExecutor(b -> {
                    b.withThreadPoolSize(2).withThreadNameFormat("SNSMacGyverEventWriter-%d");
                }).subscribe(consumer);

    }

    @Override
    public void onApplicationEvent(ApplicationReadyEvent event) {

        subscribe(event.getApplicationContext().getBean(EventSystem.class));

    }
}