Introduce Sphinx Versioning (#57)

* Sphinx Versioning

* Linking latest dir rather than copying

* Function signaturevariable name fixed

* source validaton for latest

* Try catch for git tags absence

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

* Lint and format issue solve

* lint fix

* Indentation fix

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

---------

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

Author: sankalps0549

README.md

@@ -68,6 +68,9 @@ python run.py build
 python run.py build-docs
 ```
 
+> ***Note:  When releasing a new version, update ``switcher.json`` in ``docs/source/_static/`` 
+   to include the new tag in the version dropdown for documentation.***
+
 Options:
 - `--skip-build` (`-s`): Skip building before generating docs
 
@@ -159,6 +162,7 @@ We welcome contributions! Please see our [Contributing Guide](https://github.com
 
 We use [Semantic Versioning](https://semver.org/). For available versions, see the [tags on this repository](https://github.com/Autodesk/moldflow-api/tags).
 
+
 ## License
 
 This project is licensed under the Apache License 2.0 - see the [LICENSE](https://github.com/Autodesk/moldflow-api/blob/main/LICENSE) file for details.

docs/source/_static/switcher.json

@@ -0,0 +1,38 @@
+[
+  {
+    "version": "v26.0.5",
+    "name": "v26.0.5 (latest)",
+    "url": "../v26.0.5/",
+    "is_latest": true
+  },
+  {
+    "version": "v26.0.4",
+    "name": "v26.0.4",
+    "url": "../v26.0.4/",
+    "is_latest": false
+  },
+  {
+    "version": "v26.0.3",
+    "name": "v26.0.3",
+    "url": "../v26.0.3/",
+    "is_latest": false
+  },
+  {
+    "version": "v26.0.2",
+    "name": "v26.0.2",
+    "url": "../v26.0.2/",
+    "is_latest": false
+  },
+  {
+    "version": "v26.0.1",
+    "name": "v26.0.1",
+    "url": "../v26.0.1/",
+    "is_latest": false
+  },
+  {
+    "version": "v26.0.0",
+    "name": "v26.0.0",
+    "url": "../v26.0.0/",
+    "is_latest": false
+  }
+]

docs/source/conf.py

@@ -8,6 +8,7 @@
 # https://www.sphinx-doc.org/en/master/usage/configuration.html
 import os
 import sys
+from pathlib import Path
 
 sys.path.insert(
     0, os.path.join(os.path.abspath(os.path.dirname(__file__)), '..', 'src', 'moldflow')
@@ -29,9 +30,15 @@
     'sphinx.ext.napoleon',  # Supports Google-style/Numpy-style docstrings
     'sphinx.ext.viewcode',
     'sphinx_autodoc_typehints',
+    'sphinx_multiversion',
 ]
 
 templates_path = ['_templates']
+smv_tag_whitelist = r'^v?\d+\.\d+\.\d+$'
+smv_branch_whitelist = r'^$'
+smv_remote_whitelist = r'^origin$'
+smv_latest_version = 'latest'
+
 exclude_patterns = []
 
 # -- Options for autodoc -----------------------------------------------------
@@ -53,9 +60,14 @@
 html_theme_options = {
     "back_to_top_button": False,
     "github_url": "https://github.com/Autodesk/moldflow-api",
-    "external_links": "",
+    "external_links": [
+        {"name": "Changelog", "url": "https://github.com/Autodesk/moldflow-api/releases"}
+    ],
     "footer_end": "",
     "footer_start": "copyright",
+    "navbar_start": ["navbar-logo", "version-switcher"],
+    "navbar_end": ["theme-switcher", "navbar-icon-links"],
+    "switcher": {"json_url": "_static/switcher.json", "version_match": smv_latest_version},
 }
 html_static_path = ['_static']
 html_title = "Moldflow API"
@@ -72,5 +84,34 @@ def skip_member(app, what, name, obj, skip, options):
     return skip
 
 
+def set_context_switcher(app, pagename, templatename, context, doctree):
+    """Set version_match in the switcher to show the correct version label."""
+
+    # Try output directory name (e.g., v26.0.2) - most reliable for sphinx-multiversion
+    version_name = None
+    if hasattr(app, "builder") and hasattr(app.builder, "outdir"):
+        outdir_name = Path(app.builder.outdir).name
+        if outdir_name and outdir_name != "html":
+            version_name = outdir_name
+
+    # Fallback to sphinx-multiversion context
+    if not version_name:
+        current = context.get("current_version")
+        if current:
+            version_name = getattr(current, "name", None) or (
+                current.get("name") if isinstance(current, dict) else None
+            )
+
+    # Final fallback
+    if not version_name:
+        version_name = smv_latest_version
+
+    # Update switcher config for this page
+    switcher = dict(app.config.html_theme_options.get("switcher", {}))
+    switcher["version_match"] = version_name
+    context["theme_switcher"] = switcher
+
+
 def setup(app):
     app.connect("autodoc-skip-member", skip_member)
+    app.connect("html-page-context", set_context_switcher)

docs/source/readme.rst

@@ -1255,7 +1255,12 @@ The project includes a ``run.py`` script with several useful commands:
 - ``python run.py test`` - Run tests
 - ``python run.py lint`` - Run code linting
 - ``python run.py format`` - Format code with black
-- ``python run.py build-docs`` - Build documentation
+- ``python run.py build-docs`` - Build versioned documentation (HTML uses git tags for the
+  navigation dropdown; run ``git fetch --tags`` locally before building)
+
+.. note::
+   When releasing a new version, update ``switcher.json`` in ``docs/source/_static/`` 
+   to include the new tag in the version dropdown.
 
 Contributing
 ============

requirements.txt

@@ -10,6 +10,7 @@ pydata-sphinx-theme==0.16.1
 pylint==3.3.4
 pytest==8.3.4
 sphinx==8.1.3
+sphinx-multiversion==0.2.4
 sphinx-autodoc-typehints==3.0.1
 twine==6.1.0
 PyGithub==2.7.0

run.py

@@ -62,10 +62,10 @@
 import shutil
 import glob
 from urllib.parse import urlparse
-
 import docopt
 from github import Github
 import polib
+from packaging.version import InvalidVersion, Version
 
 
 WINDOWS = platform.system() == 'Windows'
@@ -86,7 +86,9 @@
 LOCALE_DIR = os.path.join(MOLDFLOW_DIR, 'locale')
 DOCS_DIR = os.path.join(ROOT_DIR, 'docs')
 DOCS_SOURCE_DIR = os.path.join(DOCS_DIR, 'source')
+DOCS_STATIC_DIR = os.path.join(DOCS_SOURCE_DIR, '_static')
 DOCS_BUILD_DIR = os.path.join(DOCS_DIR, 'build')
+DOCS_HTML_DIR = os.path.join(DOCS_BUILD_DIR, 'html')
 COVERAGE_HTML_DIR = os.path.join(ROOT_DIR, 'htmlcov')
 DIST_DIR = os.path.join(ROOT_DIR, 'dist')
 
@@ -100,6 +102,7 @@
 VERSION_FILE = os.path.join(ROOT_DIR, VERSION_JSON)
 DIST_FILES = os.path.join(ROOT_DIR, 'dist', '*')
 PYTHON_FILES = [MOLDFLOW_DIR, DOCS_SOURCE_DIR, TEST_DIR, "run.py"]
+SWITCHER_JSON = os.path.join(DOCS_STATIC_DIR, 'switcher.json')
 
 
 def run_command(args, cwd=os.getcwd(), extra_env=None):
@@ -325,6 +328,51 @@ def build_mo():
         )
 
 
+def create_latest_alias(build_output: str) -> None:
+    """Create a 'latest' alias pointing to the newest version using symlinks when possible."""
+    version_dirs = [d for d in os.listdir(build_output) if d.startswith('v')]
+    if not version_dirs:
+        return
+
+    def version_key(v):
+        try:
+            return Version(v.lstrip('v'))
+        except InvalidVersion:
+            return Version("0.0.0")
+
+    sorted_versions = sorted(version_dirs, key=version_key, reverse=True)
+    latest_version = sorted_versions[0]
+    latest_src = os.path.join(build_output, latest_version)
+    latest_dest = os.path.join(build_output, 'latest')
+
+    # Verify source exists before proceeding
+    if not os.path.exists(latest_src):
+        logging.error("Source directory for 'latest' alias does not exist: %s", latest_src)
+        return
+
+    # Clean up any existing 'latest' entry first
+    if os.path.islink(latest_dest):
+        os.unlink(latest_dest)
+    elif os.path.isdir(latest_dest):
+        shutil.rmtree(latest_dest)
+    elif os.path.exists(latest_dest):
+        os.remove(latest_dest)
+
+    # Try creating a symbolic link first (most efficient)
+    logging.info("Creating 'latest' alias for %s", latest_version)
+    try:
+        os.symlink(latest_src, latest_dest, target_is_directory=True)
+        logging.info("Created symbolic link: latest -> %s", latest_version)
+    except (OSError, NotImplementedError) as err:
+        # Fall back to copying if symlinks aren't supported
+        logging.warning(
+            "Could not create symbolic link for 'latest' alias (%s); "
+            "falling back to copying documentation.",
+            err,
+        )
+        shutil.copytree(latest_src, latest_dest)
+
+
 def build_docs(target, skip_build):
     """Build Documentation"""
 
@@ -338,19 +386,44 @@ def build_docs(target, skip_build):
         shutil.rmtree(DOCS_BUILD_DIR)
 
     try:
-        run_command(
-            [
-                sys.executable,
-                '-m',
-                'sphinx',
-                'build',
-                '-M',
-                target,
-                DOCS_SOURCE_DIR,
-                DOCS_BUILD_DIR,
-            ],
-            ROOT_DIR,
-        )
+        if target == 'html':
+            build_output = os.path.join(DOCS_BUILD_DIR, 'html')
+            try:
+                # fmt: off
+                run_command(
+                    [
+                        sys.executable, '-m', 'sphinx_multiversion',
+                        DOCS_SOURCE_DIR, build_output
+                    ],
+                    ROOT_DIR,
+                )
+            except Exception as err:
+                logging.error(
+                    "Failed to build documentation with sphinx_multiversion.\n"
+                    "This can happen if no Git tags or branches match your version pattern.\n"
+                    "Try running 'git fetch --tags' and ensure version tags exist in the repo.\n"
+                    "Underlying error: %s",
+                    str(err),
+                )
+                # Re-raise so the outer handler can log the general failure as well.
+                raise
+            # fmt: on
+            create_latest_alias(build_output)
+        else:
+            # For other targets such as latex, pdf, etc.
+            run_command(
+                [
+                    sys.executable,
+                    '-m',
+                    'sphinx',
+                    'build',
+                    '-M',
+                    target,
+                    DOCS_SOURCE_DIR,
+                    DOCS_BUILD_DIR,
+                ],
+                ROOT_DIR,
+            )
         logging.info('Sphinx documentation built successfully.')
     except Exception as err:
         logging.error(