get readthedocs working again

.readthedocs.yaml

@@ -0,0 +1,17 @@
+# SPDX-FileCopyrightText: 2024 Jeff Epler
+#
+# SPDX-License-Identifier: GPL-3.0-only
+
+version: 2
+
+build:
+  os: ubuntu-lts-latest
+  tools:
+    python: "3"
+
+sphinx:
+  configuration: docs/conf.py
+
+python:
+  install:
+    - requirements: requirements-dev.txt

docs/conf.py

@@ -17,6 +17,13 @@ import sys
 
 sys.path.insert(0, os.path.abspath('.'))
 
+# Define the canonical URL if you are using a custom domain on Read the Docs
+html_baseurl = os.environ.get("READTHEDOCS_CANONICAL_URL", "")
+
+html_context = {}
+# Tell Jinja2 templates the build is running on Read the Docs
+if os.environ.get("READTHEDOCS", "") == "True":
+    html_context["READTHEDOCS"] = True
 
 # -- Project information -----------------------------------------------------