appstream: extract title and version

This PR extracts title and version from AppStream's name tag and
from the version property of the first release tag.

According to the AppStream docs:

> name: A human-readable name for this software component. For
> example, if the component ID was "libc", its name might be
> "GNU Standard C Library".

> Each release of the software component should have a <release/>
> tag describing it, but at least one release child must be present
> for the current release of the software. The release children
> should be sorted in a latest-to-oldest order to simplify reading
> the metadata file.

snapcraft/extractors/_metadata.py

@@ -28,6 +28,7 @@ def __init__(
         self,
         *,
         common_id: str = "",
+        title: str = "",
         summary: str = "",
         description: str = "",
         version: str = "",
@@ -39,6 +40,7 @@ def __init__(
 
         :param str: common_id: The common identifier across multiple packaging
             formats
+        :param str title: Extracted title
         :param str summary: Extracted summary
         :param str description: Extracted description
         :param str version: Extracted version
@@ -52,6 +54,8 @@ def __init__(
 
         if common_id:
             self._data["common_id"] = common_id
+        if title:
+            self._data["title"] = title
         if summary:
             self._data["summary"] = summary
         if description:
@@ -87,6 +91,15 @@ def get_common_id(self) -> str:
         common_id = self._data.get("common_id")
         return str(common_id) if common_id else None
 
+    def get_title(self) -> str:
+        """Return extracted title.
+
+        :returns: Extracted title
+        :rtype: str
+        """
+        title = self._data.get("title")
+        return str(title) if title else None
+
     def get_summary(self) -> str:
         """Return extracted summary.
 

snapcraft/extractors/appstream.py

@@ -82,6 +82,8 @@ def extract(relpath: str, *, workdir: str) -> ExtractedMetadata:
     common_id = _get_value_from_xml_element(dom, "id")
     summary = _get_value_from_xml_element(dom, "summary")
     description = _get_value_from_xml_element(dom, "description")
+    title = _get_value_from_xml_element(dom, "name")
+    version = _get_latest_release_from_nodes(dom.findall("releases/release"))
 
     desktop_file_paths = []
     desktop_file_ids = _get_desktop_file_ids_from_nodes(dom.findall("launchable"))
@@ -99,8 +101,10 @@ def extract(relpath: str, *, workdir: str) -> ExtractedMetadata:
 
     return ExtractedMetadata(
         common_id=common_id,
+        title=title,
         summary=summary,
         description=description,
+        version=version,
         icon=icon,
         desktop_file_paths=desktop_file_paths,
     )
@@ -136,6 +140,13 @@ def _get_value_from_xml_element(tree, key) -> Optional[str]:
         return None
 
 
+def _get_latest_release_from_nodes(nodes) -> Optional[str]:
+    for node in nodes:
+        if "version" in node.attrib:
+            return node.attrib["version"]
+    return None
+
+
 def _get_desktop_file_ids_from_nodes(nodes) -> List[str]:
     desktop_file_ids = []  # type: List[str]
     for node in nodes:

tests/unit/extractors/test_appstream.py

@@ -91,6 +91,16 @@ class AppstreamTestCase(unit.TestCase):
                     "expect": "test-id",
                 },
             ),
+            (
+                "title",
+                {
+                    "key": "name",
+                    "attributes": {},
+                    "param_name": "title",
+                    "value": "test-title",
+                    "expect": "test-title",
+                },
+            ),
         ],
         [
             ("metainfo", {"file_extension": "metainfo.xml"}),
@@ -457,6 +467,77 @@ def test_appstream_with_ul_in_p(self):
             ),
         )
 
+    def test_appstream_multilang_title(self):
+        file_name = "foliate.appdata.xml"
+        content = textwrap.dedent(
+            """\
+            <?xml version="1.0" encoding="UTF-8"?>
+            <component type="desktop">
+            <name>Foliate</name>
+            <name xml:lang="id_ID">Foliate_id</name>
+            <name xml:lang="pt_BR">Foliate_pt</name>
+            <name xml:lang="ru_RU">Foliate_ru</name>
+            <name xml:lang="nl_NL">Foliate_nl</name>
+            <name xml:lang="fr_FR">Foliate_fr</name>
+            <name xml:lang="cs_CS">Foliate_cs</name>
+            </component>
+        """
+        )
+
+        with open(file_name, "w") as f:
+            print(content, file=f)
+
+        metadata = appstream.extract(file_name, workdir=".")
+
+        self.expectThat(metadata.get_title(), Equals("Foliate"))
+
+    def test_appstream_release(self):
+        file_name = "foliate.appdata.xml"
+        content = textwrap.dedent(
+            """\
+            <?xml version="1.0" encoding="UTF-8"?>
+            <component type="desktop">
+            <releases>
+                <release version="1.5.3" date="2019-07-25">
+                <description>
+                    <ul>
+                    <li>Fixed Flatpak version not being able to open .mobi, .azw, and .azw3 files</li>
+                    <li>Improved Wiktionary lookup, now with links and example sentences</li>
+                    <li>Improved popover footnote extraction and formatting</li>
+                    <li>Added option to export annotations to BibTeX</li>
+                    </ul>
+                </description>
+                </release>
+                <release version="1.5.2" date="2019-07-19">
+                <description>
+                    <ul>
+                    <li>Fixed table of contents navigation not working with some books</li>
+                    <li>Fixed not being able to zoom images with Kindle books</li>
+                    <li>Fixed not being able to open books with .epub3 filename extension</li>
+                    <li>Fixed temporary directory not being cleaned after closing</li>
+                    </ul>
+                </description>
+                </release>
+                <release version="1.5.1" date="2019-07-17">
+                <description>
+                    <ul>
+                    <li>Fixed F9 shortcut not working</li>
+                    <li>Updated translations</li>
+                    </ul>
+                </description>
+                </release>
+            </releases>
+            </component>
+        """
+        )
+
+        with open(file_name, "w") as f:
+            print(content, file=f)
+
+        metadata = appstream.extract(file_name, workdir=".")
+
+        self.expectThat(metadata.get_version(), Equals("1.5.3"))
+
 
 class AppstreamUnhandledFileTestCase(unit.TestCase):
     def test_unhandled_file_test_case(self):