Support parallel build using as Sphinx extension

oembedpy/adapters/sphinx.py

@@ -92,6 +92,22 @@ def resolve_any_xref(
         # because this does not have roles and directives that are refered by outside.
         return []
 
+    def merge_domaindata(self, docnames: list[str], otherdata) -> None:
+        """Merge domain data from parallel builds.
+
+        This method merges cached oEmbed content from parallel build environments.
+        The merge strategy prioritizes entries with longer expiration times to ensure
+        the most up-to-date and longest-lived cached content is retained.
+        """
+        other_caches = otherdata.get("caches", {})
+        for cache_key, content in other_caches.items():
+            if cache_key not in self.caches:
+                self.caches[cache_key] = content
+                continue
+            exist = self.caches[cache_key]
+            if content._expired > exist._expired:
+                self.caches[cache_key] = content
+
 
 class oembed(nodes.General, nodes.Element):  # noqa: D101,E501
     pass
@@ -138,6 +154,6 @@ def setup(app: Sphinx):  # noqa: D103
     app.add_domain(OembedDomain)
     return {
         "version": __version__,
-        "parallel_read_safe": False,
+        "parallel_read_safe": True,
         "parallel_write_safe": True,
     }

tests/roots/test-parallel/conf.py

@@ -0,0 +1,10 @@
+"""Configuration is cases for default behavior."""
+
+extensions = [
+    "oembedpy.adapters.sphinx",
+]
+
+# To skip toctree
+rst_prolog = """
+:orphan:
+"""

tests/roots/test-parallel/index.rst

@@ -0,0 +1,8 @@
+=============
+Test document
+=============
+
+.. toctree::
+
+   sub1
+   sub2

tests/roots/test-parallel/sub1.rst

@@ -0,0 +1,5 @@
+==============
+Sub document 1
+==============
+
+.. oembed:: https://mastodon.cloud/@attakei/109368512525772407

tests/roots/test-parallel/sub2.rst

@@ -0,0 +1,7 @@
+==============
+Sub document 2
+==============
+
+.. oembed:: https://www.youtube.com/watch?v=Oyh8nuaLASA
+   :maxwidth: 1200
+   :maxheight: 1200

tests/roots/test-parallel/sub3.rst

@@ -0,0 +1,3 @@
+==============
+Sub document 3
+==============

tests/roots/test-parallel/sub4.rst

@@ -0,0 +1,3 @@
+==============
+Sub document 4
+==============

tests/roots/test-parallel/sub5.rst

@@ -0,0 +1,3 @@
+==============
+Sub document 5
+==============

tests/test_adapters/test_sphinx.py

@@ -4,8 +4,12 @@
 
 import pytest
 from bs4 import BeautifulSoup
+from sphinx.environment import BuildEnvironment
 from sphinx.testing.util import SphinxTestApp
 
+from oembedpy.adapters import sphinx as T
+from oembedpy.types import Link
+
 
 @pytest.fixture(scope="module")
 def rootdir():
@@ -55,3 +59,54 @@ def test_caches(app: SphinxTestApp):  # noqa
 def test_use_caches(app: SphinxTestApp):  # noqa
     app.build()
     assert len(app.env.get_domain("oembedpy").caches) == 1  # type: ignore[attr-defined]
+
+
+@pytest.mark.webtest
+@pytest.mark.sphinx("html", testroot="parallel", parallel=2)
+def test_build_parallel(app: SphinxTestApp, status):  # noqa
+    app.build()
+
+
+class TestFor_OembedDomain__merge_domaindata:
+    CACHE_KEY = ("http://example.com", 1, 1)
+
+    @pytest.mark.sphinx("html", testroot="default")
+    def test_difference_items(self, app: SphinxTestApp):
+        domain1 = T.OembedDomain(BuildEnvironment(app))
+        domain1.caches[self.CACHE_KEY] = Link(type="link", version="1.0", _extra={})
+        domain2 = T.OembedDomain(BuildEnvironment(app))
+        domain2.caches[("http://example.com", 1, 2)] = Link(
+            type="link", version="1.0", _extra={}
+        )
+        domain1.merge_domaindata([], domain2.data)
+        assert len(domain1.caches) == 2
+
+    @pytest.mark.sphinx("html", testroot="default")
+    def test_keep_main_domain(self, app: SphinxTestApp):
+        domain1 = T.OembedDomain(BuildEnvironment(app))
+        domain1.caches[self.CACHE_KEY] = Link(
+            type="link", version="1.0", title="Hello", _extra={}
+        )
+        domain2 = T.OembedDomain(BuildEnvironment(app))
+        domain2.caches[self.CACHE_KEY] = Link(
+            type="link", version="1.0", title="World", _extra={}
+        )
+        print(domain1.caches)
+        domain1.merge_domaindata([], domain2.data)
+        assert len(domain1.caches) == 1
+        print(domain1.caches)
+        assert domain1.caches[self.CACHE_KEY].title == "Hello"
+
+    @pytest.mark.sphinx("html", testroot="default")
+    def test_keep_overrides(self, app: SphinxTestApp):
+        domain1 = T.OembedDomain(BuildEnvironment(app))
+        link1 = Link(type="link", version="1.0", title="Hello", _extra={})
+        link1._expired = 3600
+        domain1.caches[self.CACHE_KEY] = link1
+        domain2 = T.OembedDomain(BuildEnvironment(app))
+        link2 = Link(type="link", version="1.0", title="World", _extra={})
+        link2._expired = 3601
+        domain2.caches[self.CACHE_KEY] = link2
+        domain1.merge_domaindata([], domain2.data)
+        assert len(domain1.caches) == 1
+        assert domain1.caches[("http://example.com", 1, 1)].title == "World"