private FSRL getFSRL(DomainFile file, Map<String, String> metadata) {
		String fsrlStr = metadata.get(IndexType.FSRL.metadataKey);
		try {
			return fsrlStr != null ? FSRL.fromString(fsrlStr).withMD5(null) : null;
		}
		catch (MalformedURLException e) {
			return null;
		}
	}
@param indexType IndexType enum
@param mappingFunc bifunc that returns value that will be used to lookup the file
@param indexedFiles map of index keyvalue to fileId (either string or list of strings)
Ghidra/Features/Base/src/main/java/ghidra/plugin/importer/ProjectIndexService.java