ququa.java

package com.dmitriid;

import com.amazonaws.auth.AWSCredentials;
import com.amazonaws.auth.BasicAWSCredentials;
import com.amazonaws.services.s3.AmazonS3;
import com.amazonaws.services.s3.AmazonS3Client;
import com.amazonaws.services.s3.model.CannedAccessControlList;
import com.amazonaws.services.s3.model.ObjectMetadata;
import com.amazonaws.services.s3.model.PutObjectRequest;
import com.amazonaws.util.Base32;
import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.dataformat.yaml.YAMLFactory;
import com.github.davidmoten.rx.FileObservable;
import rx.Observable;

import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.IOException;
import java.nio.file.WatchEvent;
import java.util.concurrent.ExecutionException;
import java.util.zip.Adler32;

import static java.nio.file.StandardWatchEventKinds.ENTRY_CREATE;

public class QuaQua {

    private static String awsFileName(File file) {
        Adler32 a = new Adler32();
        a.update(file.getName().getBytes());
        return new String(Base32.encode(String.valueOf(a.getValue()).getBytes()));
    }

    private static byte[] toPng(File file) {
        // read a jpeg from a inputFile
        try {
            BufferedImage bufferedImage = ImageIO.read(file);

            // this writes the bufferedImage into a byte array called resultingBytes
            ByteArrayOutputStream byteArrayOut = new ByteArrayOutputStream();
            ImageIO.write(bufferedImage, "png", byteArrayOut);
            return byteArrayOut.toByteArray();
        } catch (IOException e) {
            e.printStackTrace();
        }

        return null;
    }

    private static void handleFile(WatchEvent watchEvent, JsonNode configuration) {
        String path = configuration.at("/path").asText() + "/" + watchEvent.context();
        System.out.print("Uploading " + path + " ... ");
        File file = new File(path);

        System.out.print("toPng ... ");
        byte[] result = toPng(file);

        if (result == null) return;

        String newFileName = QuaQua.awsFileName(file).toLowerCase() + ".png";

        AWSCredentials credentials = new BasicAWSCredentials(configuration.at("/accessKey").asText(),
                                                             configuration.at("/secretKey").asText());


        AmazonS3 s3client = new AmazonS3Client(credentials);
        String bucketName = configuration.at("/bucket").asText();
        ObjectMetadata meta = new ObjectMetadata();
        meta.setContentType("image/png");
        meta.setContentLength(result.length);
        PutObjectRequest req = new PutObjectRequest(bucketName,
                                                    configuration.at("/folder").asText() + "/" + newFileName,
                                                    new ByteArrayInputStream(result),
                                                    meta);
        System.out.println("to S3 ... ");
        s3client.putObject(req.withCannedAcl(CannedAccessControlList.PublicRead));
        System.out.println("http://dmitriid.com/i/" + newFileName);

    }

    private static void runMonitor(JsonNode configuration) {
        File file = new File(configuration.at("/path").asText());
        Observable<WatchEvent<?>> events = FileObservable.from(file, ENTRY_CREATE);

        events.subscribe(watchEvent -> {
            QuaQua.handleFile(watchEvent, configuration);
        });

        events.publish();
    }

    static public void main(String[] args) throws ExecutionException, InterruptedException {
        CommandLine line = new CommandLine(args);
        String configFile = line.optionValue("config");

        YAMLFactory ymlFactory = new YAMLFactory();

        try {
            JsonNode configuration = new ObjectMapper().readTree(ymlFactory.createParser(new File(configFile)));
            System.out.println("Running Quaqua...");
            runMonitor(configuration);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}