Add suppport for overrides

Author: TheTripleV

sphinxext/opengraph/__init__.py

@@ -1,6 +1,7 @@
+from collections import OrderedDict
+from pathlib import Path
 from typing import Any, Dict
 from urllib.parse import urljoin
-from pathlib import Path
 
 import docutils.nodes as nodes
 from sphinx.application import Sphinx
@@ -24,13 +25,67 @@
     "tiff": "image/tiff",
 }
 
+# A selection from https://www.iana.org/assignments/media-types/media-types.xhtml#video
+VIDEO_MIME_TYPES = {
+    "3gpp": "video/3gpp",
+    "3gp2": "video/3gp2",
+    "3gpp2": "video/3gpp2",
+    "av1": "video/AV1",
+    "dv": "video/DV",
+    "h263": "video/H263",
+    "h264": "video/H264",
+    "h265": "video/H265",
+    "jpeg": "video/JPEG",
+    "jpeg2000": "video/jpeg2000",
+    "MPV": "video/MPV",
+    "ogg": "video/ogg",
+    "quicktime": "video/quicktime",
+    "raw": "video/raw",
+    "vc1": "video/vc1",
+    "vc2": "video/vc2",
+    "vp8": "video/VP8",
+    "mp4": "video/mp4",
+    "webm": "video/webm",
+    "m4v": "video/mp4",
+}
+
+# A selection from https://www.iana.org/assignments/media-types/media-types.xhtml#audio
+AUDIO_MIME_TYPES = {
+    "wave": "audio/x-wav",
+    "wav": "audio/x-wav",
+    "webm": "audio/webm",
+    "ogg": "audio/ogg",
+    "3gpp": "audio/3gpp",
+    "3gpp2": "audio/3gpp2",
+    "3gp2": "audio/3gp2",
+    "aac": "audio/aac",
+    "ac3": "audio/ac3",
+    "aptx": "audio/aptx",
+    "dv": "audio/DV",
+    "mpeg": "audio/mpeg",
+    "opus": "audio/opus",
+    "vorbis": "audio/vorbis",
+    "m3u": "audio/x-mpegurl",
+    "m3u8": "audio/x-mpegurl",
+    "mid": "audio/midi",
+    "midi": "audio/midi",
+    "mp2": "audio/mpeg",
+    "mp3": "audio/mpeg",
+    "m4a": "audio/mp4",
+    "aiff": "audio/x-aiff",
+}
+
 
 def make_tag(property: str, content: str) -> str:
     return f'<meta property="{property}" content="{content}" />\n  '
 
 
 def get_tags(
-    context: Dict[str, Any], doctree: nodes.document, config: Dict[str, Any]
+    app: Sphinx,
+    pagename: str,
+    context: Dict[str, Any],
+    doctree: nodes.document,
+    config: Dict[str, Any],
 ) -> str:
 
     # Set length of description
@@ -39,35 +94,31 @@ def get_tags(
     except ValueError:
         desc_len = DEFAULT_DESCRIPTION_LENGTH
 
+    meta = OrderedDict()
+
     # Get the title and parse any html in it
     title = get_title(context["title"], skip_html_tags=False)
     title_excluding_html = get_title(context["title"], skip_html_tags=True)
+    meta["og:title"] = title
 
     # Parse/walk doctree for metadata (tag/description)
     description = get_description(doctree, desc_len, [title, title_excluding_html])
-
-    tags = "\n  "
-
-    # title tag
-    tags += make_tag("og:title", title)
+    meta["og:description"] = description
 
     # type tag
-    tags += make_tag("og:type", config["ogp_type"])
+    meta["og:type"] = config["ogp_type"]
 
     # url tag
     # Get the URL of the specific page
     page_url = urljoin(
         config["ogp_site_url"], context["pagename"] + context["file_suffix"]
     )
-    tags += make_tag("og:url", page_url)
+    meta["og:url"] = page_url
 
     # site name tag
     site_name = config["ogp_site_name"]
     if site_name:
-        tags += make_tag("og:site_name", site_name)
-
-    # description tag
-    tags += make_tag("og:description", description)
+        meta["og:site_name"] = site_name
 
     # image tag
     # Get basic values from config
@@ -85,15 +136,40 @@ def get_tags(
             ogp_image_alt = first_image.get("alt", None)
 
     if image_url:
-        tags += make_tag("og:image", image_url)
+        meta["og:image"] = image_url
 
         # Add image alt text (either provided by config or from site_name)
         if isinstance(ogp_image_alt, str):
-            tags += make_tag("og:image:alt", ogp_image_alt)
+            meta["og:image:alt"] = ogp_image_alt
         elif ogp_image_alt is None and site_name:
-            tags += make_tag("og:image:alt", site_name)
+            meta["og:image:alt"] = site_name
         elif ogp_image_alt is None and title:
-            tags += make_tag("og:image:alt", title)
+            meta["og:image:alt"] = title
+
+    # apply overrides
+    meta.update(context.get("meta", {}))
+
+    # fix relative overrides
+    for prop in ["og:image", "og:audio", "og:video"]:
+        value = meta.get("prop", "")
+        if not (value.startswith("http://") or value.startswith("https://")):
+            meta[prop] = app.env.relfn2path(value, pagename)
+
+    # add mime types
+    def add_mime_type(prop: str, mime_types: dict):
+        if prop not in meta:
+            return
+        value = meta[prop]
+        ext = value.split(".")[-1].split("?")[0].split("#")[0].lower()
+        if ext in mime_types:
+            meta[prop + ":type"] = mime_types[ext]
+
+    add_mime_type("og:image", IMAGE_MIME_TYPES)
+    add_mime_type("og:video", VIDEO_MIME_TYPES)
+    add_mime_type("og:audio", AUDIO_MIME_TYPES)
+
+    # write tags
+    tags = "".join([make_tag(k, v) for k, v in meta.items()])
 
     # custom tags
     tags += "\n".join(config["ogp_custom_meta_tags"])
@@ -109,7 +185,7 @@ def html_page_context(
     doctree: nodes.document,
 ) -> None:
     if doctree:
-        context["metatags"] += get_tags(context, doctree, app.config)
+        context["metatags"] += get_tags(app, pagename, context, doctree, app.config)
 
 
 def setup(app: Sphinx) -> Dict[str, Any]: