Add option to pass file SHA-1 hash for upload integrity (#502)

* Add option to pass file SHA-1 hash for upload integrity

Added a sha1 attribute to FileUploadParams to enable sending the
expected hash of the file for verification that the file was not
corrupted in transit.

Fixes #328

* Add empty check for hash

src/main/java/com/box/sdk/BoxFolder.java

@@ -493,6 +493,10 @@ public BoxFile.Info uploadFile(FileUploadParams uploadParams) {
             fieldJSON.add("content_modified_at", BoxDateFormat.format(uploadParams.getModified()));
         }
 
+        if (uploadParams.getSHA1() != null && !uploadParams.getSHA1().isEmpty()) {
+            request.setContentSHA1(uploadParams.getSHA1());
+        }
+
         request.putField("attributes", fieldJSON.toString());
 
         if (uploadParams.getSize() > 0) {

src/main/java/com/box/sdk/FileUploadParams.java

@@ -13,6 +13,7 @@ public class FileUploadParams {
     private Date modified;
     private long size;
     private ProgressListener listener;
+    private String sha1;
 
     /**
      * Constructs a new FileUploadParams with default parameters.
@@ -126,4 +127,22 @@ public FileUploadParams setProgressListener(ProgressListener listener) {
         this.listener = listener;
         return this;
     }
+
+    /**
+     * Set the SHA-1 hash of the file to ensure it is not corrupted during the upload.
+     * @param sha1 the SHA-1 hash of the file.
+     * @return     this FileUploadParams for chaining.
+     */
+    public FileUploadParams setSHA1(String sha1) {
+        this.sha1 = sha1;
+        return this;
+    }
+
+    /**
+     * Gets the file's SHA-1 hash.
+     * @return the file hash.
+     */
+    public String getSHA1() {
+        return this.sha1;
+    }
 }

src/test/java/com/box/sdk/BoxFolderTest.java

@@ -763,6 +763,49 @@ public void uploadFileWithCreatedAndModifiedDatesSucceeds() {
         uploadedFile.delete();
     }
 
+    @Test
+    @Category(UnitTest.class)
+    public void testUploadFileWithSHA1SetsCorrectHeader() {
+
+        final String sha1 = "1f09d30c707d53f3d16c530dd73d70a6ce7596a9";
+
+        BoxAPIConnection api = new BoxAPIConnection("");
+        api.setRequestInterceptor(new RequestInterceptor() {
+            @Override
+            public BoxAPIResponse onRequest(BoxAPIRequest request) {
+                Assert.assertEquals(
+                        "https://upload.box.com/api/2.0/files/content",
+                        request.getUrl().toString());
+
+                List<BoxAPIRequest.RequestHeader> headers = request.getHeaders();
+
+                boolean foundHeader = false;
+
+                for (BoxAPIRequest.RequestHeader header : headers) {
+
+                    if (header.getKey() == "Content-MD5" && header.getValue() == sha1) {
+                        foundHeader = true;
+                    }
+                }
+
+                assertTrue(foundHeader);
+
+                return new BoxJSONResponse() {
+                    @Override
+                    public String getJSON() {
+                        return "{\"entries\":[{\"id\": \"0\"}]}";
+                    }
+                };
+            }
+        });
+
+        FileUploadParams uploadParams = new FileUploadParams();
+        uploadParams.setSHA1(sha1);
+
+        BoxFolder folder = new BoxFolder(api, "0");
+        folder.uploadFile(uploadParams);
+    }
+
     @Test
     @Category(IntegrationTest.class)
     public void updateFolderInfoSucceeds() {