Correctly detect attachments content type

1 files changed, 26 insertions, 10 deletions

diff --git a/juick-common/src/main/java/com/juick/server/util/HttpUtils.java b/juick-common/src/main/java/com/juick/server/util/HttpUtils.java
index dbdbc062..9f356aa5 100644
--- a/juick-common/src/main/java/com/juick/server/util/HttpUtils.java
+++ b/juick-common/src/main/java/com/juick/server/util/HttpUtils.java
@@ -22,6 +22,9 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.web.multipart.MultipartFile;
 
+import javax.imageio.ImageIO;
+import javax.imageio.ImageReader;
+import javax.imageio.stream.ImageInputStream;
 import java.io.BufferedInputStream;
 import java.io.IOException;
 import java.io.InputStream;
@@ -30,6 +33,7 @@ import java.net.URL;
 import java.net.URLConnection;
 import java.nio.file.Files;
 import java.nio.file.Paths;
+import java.util.Iterator;
 import java.util.UUID;
 
 /**
@@ -41,9 +45,15 @@ public class HttpUtils {
 
     public static URI receiveMultiPartFile(MultipartFile attach, String tmpDir) throws IOException {
         if (attach != null && !attach.isEmpty()) {
-            InputStream attachmentStream = new BufferedInputStream(attach.getInputStream());
-            String guessedContentType = URLConnection.guessContentTypeFromStream(attachmentStream);
-            String attachmentType = attachmentTypeFromContentType(guessedContentType);
+            ImageInputStream iis = ImageIO.createImageInputStream(attach.getInputStream());
+            Iterator<ImageReader> readers = ImageIO.getImageReaders(iis);
+
+            String format = StringUtils.EMPTY;
+            while (readers.hasNext()) {
+                ImageReader read = readers.next();
+                format = read.getFormatName();
+            }
+            String attachmentType = attachmentTypeFromFormat(format);
             if (attachmentType.equals("jpg") || attachmentType.equals("png")) {
                 String attachmentFName = DigestUtils.md5Hex(UUID.randomUUID().toString()) + "." + attachmentType;
                 try {
@@ -59,17 +69,25 @@ public class HttpUtils {
         return URI.create(StringUtils.EMPTY);
     }
 
-    private static String attachmentTypeFromContentType(String mime) throws IOException {
-        if (mime != null && mime.equals("image/jpeg")) {
+    private static String attachmentTypeFromFormat(String format) throws IOException {
+        if (format != null && format.equals("JPEG")) {
             return "jpg";
-        } else if (mime != null && mime.equals("image/png")) {
+        } else if (format != null && format.equals("png")) {
             return "png";
         } else {
-            throw new IOException("Wrong file type: " + mime);
+            throw new IOException("Wrong file type: " + format);
         }
     }
 
     public static URI downloadImage(URL url, String tmpDir) throws IOException {
+        ImageInputStream iis = ImageIO.createImageInputStream(url.openStream());
+        Iterator<ImageReader> readers = ImageIO.getImageReaders(iis);
+
+        String format = StringUtils.EMPTY;
+        while (readers.hasNext()) {
+            ImageReader read = readers.next();
+            format = read.getFormatName();
+        }
         URLConnection urlConn;
         try {
             urlConn = url.openConnection();
@@ -79,9 +97,7 @@ public class HttpUtils {
         }
 
         try (InputStream is = new BufferedInputStream(urlConn.getInputStream())) {
-            String mime = URLConnection.guessContentTypeFromStream(is);
-
-            String attachmentType = attachmentTypeFromContentType(mime);
+            String attachmentType = attachmentTypeFromFormat(format);
 
             String attachmentFName = DigestUtils.md5Hex(UUID.randomUUID().toString()) + "." + attachmentType;
             Files.copy(is, Paths.get(tmpDir, attachmentFName));