Menotexport

Menotexport (Mendeley-Note-Export) extracts and exports highlights, notes and PDFs from your Mendeley database

What does this do?

Menotexport is a simple python solution to help extracts and exports annotations (highlighted texts, sticky notes and notes) you made in the build-in PDF reader of Mendeley, bulk-export PDFs with annotations, and bulk-export meta-data with annotations to .bib or .ris file.

Mendeley is a desktop and web program for managing and sharing research papers. It offers free desktop clients for Windows, OSX and Linux. But the software is not open source, and their support team has been real slow in responding to customers feature requests, some of which has been proposed by many for YEARS. This tool aims at solving the following:

1. Bulk export annotated PDFs.

Annotations (highlights and notes) made inside Mendeley are saved not directly onto the relevant PDFs, but to a separate database file. Therefore these annotations can not be viewered in other PDF readers other than Mendeley itself.

The native but awkward solution to export a PDF with its annotations is: in Mendeley, open that PDF in the Mendeley PDF reader, go to Files -> Export PDF with annotations. However to export all your collections, this has to be repeated manually for each individual PDF in your library. To make it worse, the annotations exported in this manner are NOT editable: they are saved as static texts, you can't even delete a sticky note.

This tool can bulk export all PDFs with annotations while keeping your Mendeley folder structure, and the annotations are readable and editable by other PDF softwares. PDFs with no annotations are simply copied to the target location, so you have the complete library structure.

2. Extract annotation texts.

To extract texts from the highlights, sticky notes and notes (in the right-hand side-bar) in a PDF, other than Copy-n-Paste one by one, some softwares offer an automated solution.

skim on OSX has the functionality to produce a summary of all annotations.

Some versions of Foxit Reader can do that (on windows, not on the Linux version, not sure about Mac).

Pro versions of Adobe Reader may have that too.

Most of the PDF readers in Linux do not have that functionality. (Please let me know if you find one).

This tool could extract the texts from the highlights and notes in the documents in Mendeley to a plain text file, and format the information in a sensible structure using markdown syntax.

3. Export libray to .bib file.

Exporting to .bib is natively supported in Mendeley, by going to Tools -> Options -> Bibtex. There you can specify exporting the whole library to a single file or in a per-folder manner. However, your whole annotations won't be included. This tool helps you pack-up as much information as possible to a .bib file, which might be helpful for people who want to migrate to another management tool without loosing too much efforts put into Mendeley.

Fields that are exported to a .bib entry (as long as they are present in your Mendeley document record):

- citationkey
- authors
- year
- title
- publication
- volume
- issue
- pages
- doi
- abstract
- arxivId
- chapter
- country
- city
- edition
- institution
- isbn
- issn
- month
- day
- publisher
- series
- type
- keywords
- read            # Read or not
- favourite       # Marked as Favourite or starred in Mendeley 
- tags            # Tags added to a document
- file            # Location of the attached PDF on local disk 
- folder          # Folder name in the Mendeley library

Some other features

1. Export preserves sub-folder structures

Thanks to user feedbacks I realized that Mendeley supports embedded folder structures. This feature is now properly addressed: the exported PDFs, and their corresponding "file" entries in the exported .bib (or .ris) file now reflect the folder structure in Mendeley library (empty folders are omitted, embedded folders are processed recursively).

You are allowed to create folders with the same name in Mendeley, so long as they appear in different parent folders. In case you did do so, they will be labelled differently in the GUI version: e.g. "folderA", "folder1/folderA" and "folder2/folderA" are used to distinguish these three "folderA"s.

2. New highlight colors in Mendeley

Mendeley 1.16.1 introduces 7 more highlight colors, these are replicated in the exported PDFs.

3. Extra utility to help improve accuracy in highlight extractions;

Two text extracting utilities (pdfminer and pdftotext) are used to extract highlighted texts from PDFs. The user can choose to install the relevant utility to enable the pdftotext functions (installation details see below) to create better outputs than the default pdfminer results. The cost is an extra dependency to satisfy (see below), and a slight drop in execution speed. However, this new feature is optional: if you don't care about highlight extraction or don't have pdftotext available on the system, it will fall back to the pdfminer-only solution.

4. Zotero-ready output format

Use the "-z" flag (command-line version), or toggle the "For import to Zotero" option (GUI version) to re-format the exported .bib file, making it suitable to import into Zotero. Therefore to migrate over to Zotero, specify "Export PDFs", "Extract highlights", "Extract notes" and "Export to .bib" (by giving a "-pmnb" flag), process a folder or the entire Mendeley library, then point the "import" function of Zotero to the exported .bib file. Document entries with meta-data, notes (highlighted texts + notes), tags and the attached PDFs (if they exist) will be added.

5. Export to .ris format.

Export meta-data and annotations to .ris file. If -z flag is toggled, the output can be properly recognized by Zotero, and a migration to Zotero via the .ris approach can be achieved by a process with -pnmrz options.

NEW 6. Custom template formatting for exported annotations (not quite mature yet).

Annotations (notes+highlights) can be formatted in the way you like.

In the lib folder there is a file annotation_template.py which contains a working example template to format the output of the exported annotations.

To use custom template:

• in command line: add the -t option.
• in GUI: toggle the "use custom template (experimental)" button.

Currently, these variables are available in building a template:

• text : note content for a note, or highlighted texts for a highlight.
• page : page number of the note/highlight in the PDF file, not necessarily the same as printed out at the page margin.
• title: title of the document.
• tags : tag list.
• ctime: creation time.
• author : author(s) of the document.
• note_author: your name.
• citationkey: citation key.
• num : an integer id of the note/highlight, counting restarts in each document.

Put any of them in curly brackets to use them, e.g. {title}. NOTE not spaces in brackets. More instructions can be found in the template file.

For deeper modification of the output formatting, you can hack into this file: /lib/exportannotation.py.

Installation

1. Install via conda.

For command line or GUI usage on Linux (64bit), recommend installing using conda:

conda create -n menotexport python=2.7
source activate menotexport
conda install -c guangzhi menotexport

For the installation of conda (Anaconda or a lighter-weight version of Miniconda), see their official site.

2. Pre-build binary GUI for Windows

For Windows 7 and Windows 10 (64bit) (version 1.4, updated on 08-July-2017), download menotexport-gui-win7-win10.zip from Google Drive: https://drive.google.com/open?id=0B8wpnLHH0j1hTTM5cTE2TXg2b1k, unpack, then launch menotexport-gui.exe.

Version 1.4.4 (uploaded 10-Nov-2017, not fully tested yet, please provide feedbacks if this works correctly): https://drive.google.com/open?id=1rd-mOKspare4bkKWEMmm-2uwH04p-sIq.

3. Install the dependencies and use source code

If all above approaches fail, the last choise is:

• For command line or GUI usage on Linux or Mac or Win, download the zip and unzip to any folder. Make sure you have all the dependencies listed below and Python 2.7.

• NOTE that Windows user may need to manually update their sqlite3 dll. If you encounter the following error when connecting to the sqlite dataset:

Failed to recoganize the given database file.
file is encrypted or is not a database

Then download the latest version of sqlite3 from here, and copy the sqlite3.dll file to the DLLs folder in your python installation directory. Note that if you have your python environment set up using Anaconda, be sure to copy to the DLLs folder in the specific env folder.

Usage

NOTE: If you obtained this tool before 2016-04-15, I've made some changes that make it behave differently.

Command line

python menotexport.py [-h] [-p] [-m] [-n] [-b] [-r] [-s] [-z] [-f folder] dbfile outputdir

where

• -h: Show help messages.

• -p: Bulk export PDFs (including PDFs with annotations and those without annotations as well).

• -m: Extract markups (highlighted texts), also affects the outputs of the -b option.

• -n: Extract notes (sticky notes and side-bar notes), also affects the outputs of the -b option.

• -b: Export to .bib file.

• -r: Export to .ris file.

• -s: Save extracted texts to a separate txt file for each PDF. Default to save all texts to a single file.

• -z: Re-format the exported .bib and/or .ris file to a format suitable to import into Zotero. Only works when -b and/or -r are toggled.

• -f: Select to process only a Mendeley folder. Note this is case sensitive and match has to be literal. If not given, process all folders in the Mendeley library.

• dbfile: Absolute path to the Mendeley database file. In Linux systems default location is ~/.local/share/data/Mendeley\ Ltd./Mendeley\ Desktop/your_email@www.mendeley.com.sqlite

• outputdir: folder to save outputs. The Mendeley library folder structure will be preserved by creating sub-directories using folder names under outputdir.

• If -s, texts for each PDF is saved to Anno_PDFTITLE.txt (if both -m and -n are given), or to Highlights_PDFTITLE.txt or Notes_PDFTITLE.txt (if either -m or -n is given).

• If not -s, save extracted texts from all PDFs to Mendeley_annotations.txt (if both -m and -n are given), or to Mendeley_highlights.txt or Mendeley_notes.txt (if either -m or -n is given).

• If not -s, also generate another txt Mendeley_annotations_by_tags.txt where information is grouped by tags.

• If -p and -n, your sticky notes will be placed in the exported PDFs at the same locations as in Mendeley. If the document has side-bar notes (those you created in the right-hand side-bar in Mendeley), it will be transfered to the exported PDF as a sticky note at the top-left corner of the 1st page. All sticky notes are editable and deletable, but the formatting (bold, itatlic or underline) are gone.

• If -b and -m, a field annote will be created in each entry in the .bib file, containing the highlighted texts in the PDF (use with caution, see below). Similarly -b with -n will include the notes in annote (even if the document doesn't have a PDF attached to it, you can still make notes in the side-bar). Giving -m and -n will include both.

• If -b and -p, a field file will be created in each entry (those that have attached PDFs) in the .bib file, containing the path to the exported PDF, in the exported location: outputdir/folder/PDF_FILE.pdf.

Example:

To bulk export, extract and save to separate txt files:

python menotexport.py -pmns <dbfile> <outputdir>

To bulk export all PDFs and extract all annotations in Mendeley folder "Tropical_Cyclones" and save extracted annotations to a single file:

python menotexport.py -pmn -f "Tropical_Cyclones" <dbfile> <outputdir>

To bulk export all PDFs, extract all annotations in all Mendeley folders, and save annotations + meta-data to .bib file in a suitable format to import into Zotero:

python menotexport.py -pmnbz <dbfile> <outputdir>

GUI

Launch menotexport-gui.py (or menotexport-gui.exe), select the Mendeley database file and an output folder. Select the actions to perform (see above), then start.

Caveats and further notes

• NOTE that if your folders contain "/" in theirs names, it will trigger an error. Please remove "/" before using this tool.
• The bulk PDF export works with quite good accuracy, most highlights and notes are reproduced as they should be. NOTE that users have reported mis-alignments in highlighted texts when the exported PDF is opened in Qiqqa, I'm not sure it's more due to Qiqqa or this tool.
• Note extraction works with quite good accruacy.
• Highlight extraction accuracy is compromised, due to the inherent nature of the PDF format. Not all texts are correctly extracted, and the order they appear in the output may not be exactly the same as in the PDFs (top-down, left-right). The performance tends to get particularly chaotic when the highlights cover some non-roman characters (e.g. Greek letters or math symbols). DO proof read afterwards.
• Due to non-satisfactory performance in the highlights extraction, you probably want to exclude that from the exported .bib file entries. To do that, just don't toggle the -m option when using -b. The highlights will be replicated in the exported PDFs even if -m is not given.
• Highlighted texts from a single "block" of texts are treated as one record/entry. A "block" of texts is a continuous chunk of texts in the PDF, could be a whole paragraph, a single line separated from others, or a single isolated word.
• Citationkeys and tags are added to the extracted texts in the save .txt files to facilitate further information processes, both can be editted in Mendeley.
• If choose to save all annotations to a single file, the programme also re-structure the extracted texts and organize them by their tags before saving to a separate file. Pieces of texts from a PDF that isn't taged are given a tag of @None.
• This is not necessarily a bug but might be worth noting: if you choose to process all the Mendeley folders and export the PDFs, the duplicated files in different folders will be duplicated on the disk as well, therefore taking up multiples of disk spaces. Similarly the .bib file may contain duplicated entries, with different "folder" and "file" fields.
• Sometimes your edits inside Mendeley may not be saved immediately to the database file. In such cases just reboot Mendeley. No needed to reboot Menotexport (if you are using the GUI), as each time you press the "start" button it will issue a new connection to the database.
• Possible follow-ups one can do: re-format the extracted txts to PDFs, docs or sync into your Evernote account, will probably implement these in a later version.
• To batch upload to Evernote, check out this repo: txt2evernote.
• "Canonical documents", which are documents saved in Mendeley's "My Library" (kind of the root folder) but not belonging to any user created folder, are now properly processed, and the results are saved to a directory "Canonical-My Library".
• A note for myself: when building the windows exe, downgrade setuptools to 19.2, use pandas=0.16, don't use pyinstaller inside anaconda otherwise the result package will be 10x bigger, may need to install pyinstaller from its git.

Dependencies

Developed in python2.7. NOT compatible with python3+ (pdfminer doesn't support python3).

1. It requires the following python packages:

   • PyPDF2
   • sqlite3
   • pandas (0.16 or later)
   • pdfminer (NOTE: version 2014+ is needed, the one in the Ubuntu repository has been out of date at the time of writing. Please check to make sure. If you get an error of "ImportError: No module named pdfdocument", you probably got an older version.)
   • numpy
   • BeautifulSoup4

2. (Optional but recommended) For better performances in highlight extraction, it further requires the pdftotext software.

   • Linux: pdftotext comes with most popular Linux distros. In case you need to install it:

     sudo apt-get install poppler-utils
     

   • Windows: Download the poppler package from here, unpack to any folder, then add the path to the pdftotext.exe file (e.g. D:\Downloads\poppler-0.44_x86\poppler-0.44\bin) to your PATH environmental variable. How to do this is system version dependent, please google. NOTE that the pdftotext in the xpdf package for Windows does not work: it doesn't have coordinate-based portion extraction.

It further incorporates (with minor adjustments) the pdfannotation.py file from the Menextract2pdf project.

It further incorporates (with no adjustments) the pylatexenc module from the pylatexenc project.

Platform/OS

The software is tested on Linux and Windows 7, 10. Should also run on Mac.

Versions

• 1.4.4: Add custom annotation templation support (not mature yet). Fix auto-renaming function fixed.
• 1.4: Add export to .ris format. "Canonical documents", which are documents saved in Mendeley's "My Library" (kind of the root folder) but not belonging to any user created folder, are now properly processed, and the results are saved to a directory "Canonical-My Library".
• 1.3: Call pdftotext to work with pdfminer for better highlight extraction, if pdftotext not available, fall back to old approach. Some other improvements in highlight extraction. Add special formatting of the .bib file for Zotero import.
• 1.2: Works with subfolders. If a folder is chosen to process, also includes all subfolders. Replicates the 8 different highlight colors introduced in Mendeley 1.16.1 version, in the exported PDFs.
• 1.1: Added export of non-annotated PDFs and export to .bib.
• 1.0: Added GUI and Windows version
• 0.1: First release

Licence

The script is distributed under the GPLv3. The pdfannotations.py file is LGPLv3. pylatexenc is under MIT license.

Related projects

• Mendeley2Zotero
• Adios_Mendeley
• Menextract2pdf
• txt2evernote
• tagextract