From c6b6ef1572e35299b84e54b9eb1c09ca286a82c3 Mon Sep 17 00:00:00 2001
From: Nicholas Landry <nicholas.landry.91@gmail.com>
Date: Mon, 9 Jan 2023 12:50:15 -0500
Subject: [PATCH] Added the ability to list datasets (#266)

* Added the ability to list datasets

* fix requirements
---
 requirements/default.txt  |  2 +-
 xgi/readwrite/xgi_data.py | 19 +++++++++++++------
 2 files changed, 14 insertions(+), 7 deletions(-)

diff --git a/requirements/default.txt b/requirements/default.txt
index 6e66614b1..0ed826c10 100644
--- a/requirements/default.txt
+++ b/requirements/default.txt
@@ -1,6 +1,6 @@
 numpy>=1.19
 scipy>=1.5
 pandas>=1.0
-networkx>=2.0
+networkx>=2.0,<3.0
 requests>=2.0
 matplotlib>=3.3
\ No newline at end of file
diff --git a/xgi/readwrite/xgi_data.py b/xgi/readwrite/xgi_data.py
index 907b97725..d0ecf8838 100644
--- a/xgi/readwrite/xgi_data.py
+++ b/xgi/readwrite/xgi_data.py
@@ -12,7 +12,7 @@
 
 
 def load_xgi_data(
-    dataset,
+    dataset=None,
     cache=True,
     read=False,
     path="",
@@ -24,9 +24,10 @@ def load_xgi_data(
 
     Parameters
     ----------
-    dataset : str
+    dataset : str, default: None
         Dataset name. Valid options are the top-level tags of the
-        index.json file in the xgi-data repository.
+        index.json file in the xgi-data repository. If None, prints
+        the list of available datasets.
     cache : bool, optional
         Whether to cache the input data
     read : bool, optional
@@ -94,14 +95,15 @@ def download_xgi_data(dataset, path=""):
     jsonfile.close()
 
 
-def _request_from_xgi_data(dataset):
+def _request_from_xgi_data(dataset=None):
     """Request a dataset from xgi-data.
 
     Parameters
     ----------
-    dataset : str
+    dataset : str, default: None
         Dataset name. Valid options are the top-level tags of the
-        index.json file in the xgi-data repository.
+        index.json file in the xgi-data repository. If None, prints
+        the list of available datasets.
 
     Returns
     -------
@@ -123,6 +125,11 @@ def _request_from_xgi_data(dataset):
 
     if r.ok:
         index_data = r.json()
+
+        if dataset is None:
+            print("Available datasets are the following:")
+            print(*index_data, sep="\n")
+            return
     else:
         raise XGIError(f"Error: HTTP response {r.status_code}")