feat: add progress logger to Downloader.downloadFile

feat: prevent divide by zero

feat: prevent divide by zero

Author: rtroilo

core/src/main/java/com/graphhopper/util/Downloader.java

@@ -17,9 +17,13 @@
  */
 package com.graphhopper.util;
 
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
 import java.io.*;
 import java.net.HttpURLConnection;
 import java.net.URL;
+import java.nio.file.Path;
 import java.util.function.LongConsumer;
 import java.util.zip.GZIPInputStream;
 import java.util.zip.Inflater;
@@ -29,6 +33,7 @@
  * @author Peter Karich
  */
 public class Downloader {
+    private static final Logger logger = LoggerFactory.getLogger(Downloader.class);
     private static final int BUFFER_SIZE = 8 * 1024;
     private final String userAgent;
     private String referrer = "http://graphhopper.com";
@@ -111,8 +116,10 @@ public void downloadFile(String url, String toFile) throws IOException {
         InputStream iStream = fetch(conn, false);
         BufferedOutputStream writer = new BufferedOutputStream(new FileOutputStream(toFile), BUFFER_SIZE);
         InputStream in = new BufferedInputStream(iStream, BUFFER_SIZE);
-        try {
-            in.transferTo(writer);
+        String file = Path.of(toFile).getFileName().toString();
+        logger.info("Downloading {} [{}]", url, conn.getContentLengthLong());
+        try (OutputStream progress = new ProgressOutputStream(writer, "downloading %s ..".formatted(file), conn.getContentLengthLong(), logger::info)) {
+            in.transferTo(progress);
         } finally {
             Helper.close(iStream);
             Helper.close(writer);

core/src/main/java/com/graphhopper/util/ProgressOutputStream.java

@@ -0,0 +1,85 @@
+package com.graphhopper.util;
+
+import org.apache.commons.lang3.time.DurationFormatUtils;
+import org.apache.commons.lang3.time.StopWatch;
+
+import java.io.IOException;
+import java.io.OutputStream;
+import java.util.function.Consumer;
+
+class ProgressOutputStream extends OutputStream {
+    private final OutputStream out;
+    private final long max;
+    private final Consumer<String> log;
+    private final String progressRenderString;
+
+    private long current = 0;
+    private long speed = 0;
+
+    private final StopWatch time;
+    private final StopWatch totalTime;
+
+
+    public ProgressOutputStream(OutputStream out, String task, long max, Consumer<String> log) {
+        this.out = out;
+        this.max = max;
+        this.log = log;
+        if (max > 0) {
+            this.progressRenderString = "%s %%%dd/%d (%%3d%%%%) [%%.2f MB/s / %%.2f MB/s] %%s"
+                    .formatted(task, Long.toString(max).length(), max);
+        } else {
+            this.progressRenderString = "%s %%d/? [%%.2f Mbps / %%.2f Mbps] %%s".formatted(task);
+        }
+
+        this.time = StopWatch.createStarted();
+        this.totalTime = StopWatch.createStarted();
+
+    }
+
+    private void progress(long n) {
+        current += n;
+        speed += n;
+        if (time.getTime() >= 1000) {
+            triggerLog();
+            time.reset();
+            time.start();
+            speed = 0;
+        }
+    }
+
+    private void triggerLog() {
+        log.accept(render((speed) / (Math.max(time.getTime(), 1) * 1000.0), (current) / (Math.max(totalTime.getTime(), 1) * 1000.0)));
+    }
+
+    private String render(double mbits, double mbitsTotal) {
+        if (max > 0) {
+            return progressRenderString
+                    .formatted(current, (int) ((current / (double) max) * 100),
+                            mbits, mbitsTotal,
+                            DurationFormatUtils.formatDuration(totalTime.getTime(), "mm:ss.SSS"));
+        }
+        return progressRenderString
+                .formatted(current,
+                        mbits, mbitsTotal,
+                        DurationFormatUtils.formatDuration(totalTime.getTime(), "mm:ss.SSS"));
+
+    }
+
+    @Override
+    public void write(byte[] b, int off, int len) throws IOException {
+        out.write(b, off, len);
+        progress(len);
+    }
+
+    @Override
+    public void write(int b) throws IOException {
+        out.write(b);
+        progress(1);
+    }
+
+    @Override
+    public void close() throws IOException {
+        out.close();
+        triggerLog();
+    }
+}