Added: extra dependencies for data (#209)

Author: signebedi

requirements/data.txt

@@ -0,0 +1,3 @@
+openpyxl<4.0.0
+pandas<3.0.0
+xlrd<3.0.0

setup.py

@@ -18,12 +18,17 @@ def read_version():
 with open("README.md", "r", encoding="utf-8") as fh:
     long_description = fh.read()
 
-requirements_file = os.getenv('REQUIREMENTS', 'requirements/base.txt')
+requirements_file = "requirements/base.txt"
 
 # Read requirements/base.txt for install_requires
 with open(requirements_file, encoding="utf-8") as f:
     install_requires = f.read().splitlines()
-    
+
+data_extras_file = "requirements/data.txt"
+
+with open(data_extras_file, encoding="utf-8") as f:
+    install_extras_data = f.read().splitlines()
+
 setup(
     name='libreforms_fastapi',
     version=version,
@@ -46,4 +51,7 @@ def read_version():
             'libreformsctl=libreforms_fastapi.cli.__init__:cli',
         ],
     },
+    extras_require={
+        "data": install_extras_data,
+    },
 )