From 45de1ae50e0dce96e95606bb4d0f8de3d6ced847 Mon Sep 17 00:00:00 2001
From: Alexander Bonkowski <57258530+ab5424@users.noreply.github.com>
Date: Thu, 2 May 2024 14:36:03 +0200
Subject: [PATCH] Make BeautifulSoup optional (#3774)

Signed-off-by: Alexander Bonkowski <57258530+ab5424@users.noreply.github.com>
---
 dev_scripts/update_pt_data.py | 8 +++++++-
 pymatgen/io/vasp/help.py      | 8 +++++++-
 requirements-optional.txt     | 1 +
 requirements.txt              | 1 -
 4 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/dev_scripts/update_pt_data.py b/dev_scripts/update_pt_data.py
index 8799adef19b..58bdc301f99 100644
--- a/dev_scripts/update_pt_data.py
+++ b/dev_scripts/update_pt_data.py
@@ -11,12 +11,17 @@
 from itertools import product
 
 import requests
-from bs4 import BeautifulSoup
+from monty.dev import requires
 from monty.serialization import dumpfn, loadfn
 from ruamel import yaml
 
 from pymatgen.core import Element, get_el_sp
 
+try:
+    from bs4 import BeautifulSoup
+except ImportError:
+    BeautifulSoup = None
+
 ptable_yaml_path = "periodic_table.yaml"
 
 
@@ -231,6 +236,7 @@ def gen_iupac_ordering():
         periodic_table[el]["IUPAC ordering"] = iupac_ordering_dict[get_el_sp(el)]
 
 
+@requires(BeautifulSoup, "BeautifulSoup must be installed to use this method.")
 def add_electron_affinities():
     """Update the periodic table data file with electron affinities."""
 
diff --git a/pymatgen/io/vasp/help.py b/pymatgen/io/vasp/help.py
index f057cb09b81..92c54913caf 100644
--- a/pymatgen/io/vasp/help.py
+++ b/pymatgen/io/vasp/help.py
@@ -5,12 +5,18 @@
 import re
 
 import requests
-from bs4 import BeautifulSoup
+from monty.dev import requires
+
+try:
+    from bs4 import BeautifulSoup
+except ImportError:
+    BeautifulSoup = None
 
 
 class VaspDoc:
     """A VASP documentation helper."""
 
+    @requires(BeautifulSoup, "BeautifulSoup must be installed to fetch from the VASP wiki.")
     def __init__(self) -> None:
         """Init for VaspDoc."""
         self.url_template = "http://www.vasp.at/wiki/index.php/%s"
diff --git a/requirements-optional.txt b/requirements-optional.txt
index b5a29956285..2c5019a6523 100644
--- a/requirements-optional.txt
+++ b/requirements-optional.txt
@@ -1,4 +1,5 @@
 ase>=3.22.1
+beautifulsoup4==4.12.2
 BoltzTraP2>=22.3.2
 chemview>=0.6
 f90nml>=1.4.3
diff --git a/requirements.txt b/requirements.txt
index 2794ea355e0..384479945c4 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -11,7 +11,6 @@ spglib==2.1.0
 pandas==2.1.1
 networkx==3.1
 plotly==5.17.0
-beautifulsoup4==4.12.2
 uncertainties==3.1.7
 Cython==3.0.2
 pybtex==0.24.0