Usage of local.bitstream.redirectToURL

[kosarko]

@milanmajchrak @vidiecan
This field (local.bitstream.redirectToURL) was originally used to provide an alternative/faster way to provide files to users. The need for that was mostly replaced by using X-Sendfile (https://www.nginx.com/resources/wiki/start/topics/examples/x-accel/).

In

clarin-dspace/dspace-xmlui/src/main/java/org/dspace/app/xmlui/cocoon/BitstreamReader.java

Lines 443 to 446 in 8a6ba5c

	Metadatum[] mds = bitstream.getMetadataByMetadataString("local.bitstream.redirectToURL");
	if(mds != null && mds.length == 1){
	if(org.apache.commons.lang3.StringUtils.isNotBlank(mds[0].value)){
	this.redirectToURL = mds[0].value;

when a bitstream is accessed we check for this md field. If it is there then

clarin-dspace/dspace-xmlui/src/main/java/org/dspace/app/xmlui/cocoon/BitstreamReader.java

Lines 821 to 825 in 8a6ba5c

	}
	else if(org.apache.commons.lang3.StringUtils.isNotBlank(this.redirectToURL)){
	response.sendRedirect(this.redirectToURL);
	}else {
	if (byteRange != null) {

a redirect is sent (instead of dspace sending bytes read from storage).

In v7 this field is used differently (https://github.com/dataquest-dev/DSpace/wiki/Developing-backend#configure-big-file-limit); so:

• pingback Metadata changes #1045 (which tries to list these sort of changes)
• what does the data pump do with the existing values (this is bitstream metadata in v5)
• is it kept after the file has been uploaded? What happens if I upload multiple files this way; does the item keep only the latest path? From the wiki it seems this is now item level metadata?

[milanmajchrak]

2. The data pump just copy that metadata value from v5 to v7
3. Some refactoring is needed, after refactoring the big upload file will looks like this:

• bigfile input field will be moved to the Upload step (file path, file description; with upload button)
• bigfile Item's metadata won't be deleted after upload
• this input field will be allowed only for admin
• this approach allows the admin to upload more big files
• redirectToURL metadata is bitstream's level metadata, not item's

After update:

• The Item's redirectToUrl metadata is removed after every upload, that means you can upload whatever file you want
• The cfg property which determines whether the file is removed after upload, was set to false, meaning "do not delete that file."

[kosarko]

The data pump just copy that metadata value from v5 to v7

@milanmajchrak Can the pump drop the values and issue some sort of NOTICE? I mean if the functionality (the actual redirect) is no longer there why keep it?

[milanmajchrak]

The data pump just copy that metadata value from v5 to v7
@milanmajchrak Can the pump drop the values and issue some sort of NOTICE? I mean if the functionality (the actual redirect) is no longer there why keep it?

Of course, the pump can ignore updating specific metadata values and add a WARN message to the logs.

[kosarko]

yes, ignore these metadata...