Add lazy MD5 calculation for downloaded file by FileDownloader

Author: Roberto Sora

Diff for: arduino-core/src/cc/arduino/utils/network/FileDownloader.java

@@ -29,6 +29,7 @@
 
 package cc.arduino.utils.network;
 
+import cc.arduino.utils.FileHash;
 import org.apache.commons.compress.utils.IOUtils;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -44,6 +45,7 @@
 import java.net.URL;
 import java.nio.file.Files;
 import java.nio.file.Paths;
+import java.security.NoSuchAlgorithmException;
 import java.util.Observable;
 import java.util.Optional;
 
@@ -65,6 +67,8 @@ public enum Status {
   private long downloaded;
   private final URL downloadUrl;
 
+  private String downloadedContentMD5;
+
   private final File outputFile;
   private InputStream stream = null;
   private Exception error;
@@ -74,6 +78,20 @@ public FileDownloader(URL url, File file) {
     outputFile = file;
     downloaded = 0;
     initialSize = 0;
+
+  }
+
+  public String getDownloadedContentMD5() {
+    if (this.downloadedContentMD5 == null && this.status == Status.COMPLETE) {
+      try {
+        downloadedContentMD5 = FileHash.hash(this.outputFile, "MD5");
+      } catch (NoSuchAlgorithmException e) {
+        log.warn("Cannot calculate the downloaded file MD5: ", e.getCause());
+      } catch (IOException e) {
+        log.warn("Cannot open the downloaded file: ", e.getCause());
+      }
+    }
+    return downloadedContentMD5;
   }
 
   public long getInitialSize() {
@@ -132,7 +150,8 @@ public void download(boolean noResume) throws InterruptedException {
 
   private void saveLocalFile() {
     try {
-      Files.write(outputFile.toPath(), Files.readAllBytes(Paths.get(downloadUrl.getPath())));
+      Files.write(outputFile.toPath(),
+                  Files.readAllBytes(Paths.get(downloadUrl.getPath())));
       setStatus(Status.COMPLETE);
     } catch (Exception e) {
       setStatus(Status.ERROR);
@@ -147,21 +166,24 @@ private void downloadFile(boolean noResume) throws InterruptedException {
       setStatus(Status.CONNECTING);
 
       final File settingsFolder = BaseNoGui.getPlatform().getSettingsFolder();
-      final String cacheFolder = Paths.get(settingsFolder.getPath(), "cache").toString();
-      final FileDownloaderCache fileDownloaderCache = FileDownloaderCache.getFileCached(cacheFolder, downloadUrl);
+      final String cacheFolder = Paths.get(settingsFolder.getPath(), "cache")
+        .toString();
+      final FileDownloaderCache fileDownloaderCache = FileDownloaderCache
+        .getFileCached(cacheFolder, downloadUrl);
 
       if (!fileDownloaderCache.isChange()) {
         try {
-          final Optional<File> fileFromCache =
-            fileDownloaderCache.getFileFromCache();
+          final Optional<File> fileFromCache = fileDownloaderCache
+            .getFileFromCache();
           if (fileFromCache.isPresent()) {
             FileUtils.copyFile(fileFromCache.get(), outputFile);
             setStatus(Status.COMPLETE);
             return;
           }
         } catch (Exception e) {
           log.warn(
-            "Cannot get the file from the cache, will be downloaded a new one ", e.getCause());
+            "Cannot get the file from the cache, will be downloaded a new one ",
+            e.getCause());
         }
       }
 
@@ -175,14 +197,15 @@ private void downloadFile(boolean noResume) throws InterruptedException {
       randomAccessOutputFile = new RandomAccessFile(outputFile, "rw");
       randomAccessOutputFile.seek(initialSize);
 
-      final HttpURLConnection connection = new HttpConnectionManager(downloadUrl)
-        .makeConnection((c) -> setDownloaded(0));
+      final HttpURLConnection connection = new HttpConnectionManager(
+        downloadUrl).makeConnection((c) -> setDownloaded(0));
       final int resp = connection.getResponseCode();
 
       if (resp < 200 || resp >= 300) {
         IOUtils.closeQuietly(randomAccessOutputFile);
         Files.deleteIfExists(outputFile.toPath());
-        throw new IOException("Received invalid http status code from server: " + resp);
+        throw new IOException(
+          "Received invalid http status code from server: " + resp);
       }
 
       // Check for valid content length.
@@ -218,6 +241,9 @@ private void downloadFile(boolean noResume) throws InterruptedException {
       IOUtils.closeQuietly(randomAccessOutputFile);
       fileDownloaderCache.fillCache(outputFile);
       setStatus(Status.COMPLETE);
+      log.info("Downloaded Successfully {}, file MD5: {}", downloadUrl,
+               this.getDownloadedContentMD5());
+
     } catch (InterruptedException e) {
       setStatus(Status.CANCELLED);
       // lets InterruptedException go up to the caller