fix for #7184 spaces changed in s3 direct download

doc/release-notes/7184-spaces-in-filenames.md

@@ -0,0 +1,7 @@
+## Notes for Tool Developers and Integrators
+
+### Filenames
+
+Dataverse Installations using S3 storage will no longer replace spaces in file names with the + character. If your tool or integration has any special handling around this character change, you can remove it.
+
+(review this note if this is in the same release as the fix for #7188)

src/main/java/edu/harvard/iq/dataverse/dataaccess/S3AccessIO.java

@@ -838,7 +838,8 @@ public String generateTemporaryS3Url() throws IOException {
             // Most browsers are happy with just "filename="+URLEncoder.encode(this.getDataFile().getDisplayName(), "UTF-8") 
             // in the header. But Firefox appears to require that "UTF8" is 
             // specified explicitly, as below:
-            responseHeaders.setContentDisposition("attachment; filename*=UTF-8''"+URLEncoder.encode(this.getDataFile().getDisplayName(), "UTF-8"));
+            responseHeaders.setContentDisposition("attachment; filename*=UTF-8''" + URLEncoder.encode(this.getDataFile().getDisplayName(), "UTF-8")
+                    .replaceAll("\\+", "%20"));
             // - without it, download will work, but Firefox will leave the special
             // characters in the file name encoded. For example, the file name 
             // will look like "1976%E2%80%932016.txt" instead of "1976–2016.txt",