A tiny Vim Snippet

Table of Contents

A tiny code snippet for Vim using UltiSnips plugin that can convert links to papers into APA citation in markdown.

The first snippet auto-completes alin and form a block of code with the link inside. The second snippet evaluates the link and returns the APA citation in markdown.

Usage

1. Copy the code below into your UltiSnips folder, which on my Mac is ~/.vim/UltiSnips/.
2. Open a markdown file, type alin and press tab. This will create a block of code with the link inside; press tab again to complete the link.

Caveat Emptor

I was only able to find an API for arxiv but not for other websites like openreview. This can break if the website changes its structure.

Code

snippet alin "create markdown links from paper links" w
alin $1 alin$0    
endsnippet

priority 1000
snippet 'alin(.*)alin' "evaluate link and return APA cite in markdown" wr
`!p
import requests
from bs4 import BeautifulSoup
import json
import warnings
warnings.filterwarnings("ignore")

def get_arxiv_metadata(arxiv_id):
    url = f'http://export.arxiv.org/api/query?id_list={arxiv_id}'
    response = requests.get(url)
    
    feed = BeautifulSoup(response.content)
    entry = feed.find('entry')

    print(entry)

    print(entry.find_all('author'))

    authors = [author.find('name').text for author in entry.find_all('author')]
    published_date = entry.find('published').text
    year = published_date.split('-')[0]
    return authors, year

def get_openreview_metadata(url):
    response = requests.get(url)
    soup = BeautifulSoup(response.content, 'html.parser')

    script_tag = soup.find('script', {'id': '__NEXT_DATA__'})
    if not script_tag:
        raise Exception('Data script tag not found')

    data_str = script_tag.string
    data_json = json.loads(data_str)
    
    authors = data_json['props']['pageProps']['forumNote']['content']['authors']
    if isinstance(authors, dict):
        authors = authors['value']
    
    try:
        year = data_json['props']['pageProps']['forumNote']['invitation']
    except KeyError:
        year = data_json['props']['pageProps']['forumNote']['invitations'][0]

    # year of the form neurips.cc/2021/...
    year = year.split('/')[1]
    return authors, year

def format_authors(authors):
    if len(authors) == 1:
        # use last names only
        return authors[0].split(' ')[-1]
    elif len(authors) == 2:
        return f"{authors[0].split(' ')[-1]} and {authors[1].split(' ')[-1]}"
    else:
        print(authors)
        return f"{authors[0].split(' ')[-1]} et al."

def generate_citation(arxiv_link, type = 'arxiv'):
    if type == 'arxiv':
        arxiv_link = arxiv_link.replace('/pdf/', '/abs/').replace('.pdf', '')
        arxiv_id = arxiv_link.split('/')[-1]
        authors, year = get_arxiv_metadata(arxiv_id)
        formatted_authors = format_authors(authors)
        citation = f"[{formatted_authors}, {year}]({arxiv_link})"
    
    elif type == 'openreview':
        # openreview_id = arxiv_link.split('/')[-1].split('?')[-1].split('=')[-1]
        # replace pdf with forum
        arxiv_link = arxiv_link.replace('/pdf?', '/forum?')
        
        authors, year =  get_openreview_metadata(arxiv_link)
        formatted_authors = format_authors(authors)
        citation = f"[{formatted_authors}, {year}]({arxiv_link})"
    return citation

arxiv_link = f"{match.group(1)}"
arxiv_link = arxiv_link.strip()

type = None
if 'arxiv' in arxiv_link:
    type = 'arxiv'
elif 'openreview' in arxiv_link:
    print('openreview')
    type = 'openreview'

snip.rv = generate_citation(arxiv_link, type)
`
endsnippet