I'm using Mendeley API to retrieve and also upload articles from/to my Mendeley library. Are these two possible with the Mendeley API?
- Download (ie, export) pdf and the annotations separately?
- Upload (ie, import) pdf + annotations?
Also, is the annotation format something standard? For example can I generate the annotations through a custom app and then import in Mendeley web app?
Annotations within a PDF are simply part of overall content. See object number 12 below the file.PDF where the only significant content is just that one comment.
So annotations are usually found near the end of file (but could be first object too). Often grouped together (separate from their pages), but not usually outside of the PDF.
They are exportable and importable in many cases from acrobat reader etc. See the righthand dialog box.
So if Mendeley is using Adobe Standard Annotations they travel inside the file.pdf
The import/export format that is easiest to use is FDF as it resembles PDF entries, and that same single exported entry is shown at middle bottom.
Note that annotations such as a small highlight, consume much more storage than one may expect and even deletions may be retained inside the PDF adding to the bloat.
To be used in a web context it is the Adobe Collaborative System server or (equivalent), that imports and exports usually via FDF replacements. You can do it manually but keeping multiple users metadata in sync is a complex task.