Implement Read the docs. (#181)

* Implement Read the docs.

* New docs URL.

* Legacy documentation message.

Author: trexfeathers

.readthedocs.yml

@@ -0,0 +1,16 @@
+version: 2
+
+build:
+    image: latest
+
+conda:
+    environment: requirements/cf-units.yml
+
+sphinx:
+    configuration: doc/source/conf.py
+    fail_on_warning: false
+
+python:
+    install:
+        - method: setuptools
+          path: .

README.md

@@ -1,4 +1,4 @@
-# [cf-units](https://scitools.org.uk/cf-units/docs/latest/)
+# [cf-units](https://cf-units.readthedocs.io/en/latest/)
 
 #### Units of measure as defined by the Climate and Forecast (CF) metadata conventions.
 
@@ -43,7 +43,7 @@ conventions.
 Provision of a wrapper class to support Unidata/UCAR UDUNITS-2 library, and the
 cftime calendar functionality.
 
-Documentation can be found at <https://scitools.org.uk/cf-units/docs/latest/>.
+Documentation can be found at <https://cf-units.readthedocs.io/en/latest/>.
 
 ### Example
 

doc/source/conf.py

@@ -4,21 +4,7 @@
 # See COPYING and COPYING.LESSER in the root of the repository for full
 # licensing details.
 
-# -*- coding: utf-8 -*-
-#
-# cf_units documentation build configuration file, created by
-# sphinx-quickstart on Thu Jan 21 12:03:35 2016.
-#
-# This file is execfile()d with the current directory set to its
-# containing dir.
-#
-# Note that not all possible configuration values are present in this
-# autogenerated file.
-#
-# All configuration values have a default; values that are commented out
-# serve to show the default.
-
-import cf_units
+from importlib import metadata
 
 extensions = [
     "sphinx.ext.autodoc",
@@ -35,18 +21,13 @@
 project = "cf-units"
 copyright = "Copyright cf-units contributors"
 
-
-current_version = cf_units.__version__
+current_version = metadata.version("cf_units")
 version = current_version.split("+")[0]
 release = current_version
 
-
 # -- Options for HTML output ----------------------------------------------
 
 html_theme = "alabaster"
 
-html_static_path = ["_static"]
-
-
 # Example configuration for intersphinx: refer to the Python standard library.
 intersphinx_mapping = {"http://docs.python.org/": None}

doc/source/index.rst

@@ -14,6 +14,9 @@ Contents:
     unit
     utilities
 
+cf-units is part of SciTools, for more information see https://scitools.org.uk/.
+For **cf-units 2.0** and earlier documentation please see the
+`legacy documentation <https://scitools.org.uk/cf-units/docs/v2.0/>`_.
 
 
 Indices and tables

requirements/py37.yml

@@ -25,3 +25,7 @@ dependencies:
 # dev dependencies
   - pip
   - pre-commit
+
+# docs dependencies
+  - setuptools_scm
+  - sphinx

requirements/py38.yml

@@ -25,3 +25,7 @@ dependencies:
 # dev dependencies
   - pip
   - pre-commit
+
+# docs dependencies
+  - setuptools_scm
+  - sphinx

requirements/py39.yml

@@ -25,3 +25,7 @@ dependencies:
 # dev dependencies
   - pip
   - pre-commit
+
+# docs dependencies
+  - setuptools_scm
+  - sphinx

setup.cfg

@@ -49,6 +49,9 @@ python_requires =
 zip_safe = False
 
 [options.extras_require]
+docs =
+    setuptools_scm
+    sphinx
 test =
     codecov
     cython
@@ -58,6 +61,7 @@ test =
     pytest-cov
 all =
     pre-commit
+    %(docs)s
     %(test)s
 
 [flake8]