Add QT extension

extensions/desktop/command-chain/hooks-configure-fonts

@@ -1,5 +1,5 @@
 #!/bin/bash
 
-set -- "${SNAP}/gnome-platform/command-chain/hooks-configure-fonts" "$@"
+set -- "${SNAP}/qt-framework/command-chain/hooks-configure-fonts" "$@"
 # shellcheck source=/dev/null
 source "${SNAP}/snap/command-chain/run"

schema/snapcraft.json

@@ -914,6 +914,7 @@
                                     "gnome-3-34",
                                     "gnome-3-38",
                                     "kde-neon",
+                                    "qt-framework",
                                     "ros1-noetic",
                                     "ros2-foxy"
                                 ]

snapcraft/extensions/qt_framework.py

@@ -0,0 +1,217 @@
+# -*- Mode:Python; indent-tabs-mode:nil; tab-width:4 -*-
+#
+# Copyright 2022 Canonical Ltd.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License version 3 as
+# published by the Free Software Foundation.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+"""Generic QT Framework extension to support core22 and onwards."""
+import dataclasses
+import functools
+from typing import Any, Dict, List, Optional, Tuple
+
+from overrides import overrides
+
+from .extension import Extension, get_extensions_data_dir, prepend_to_env
+
+_SDK_SNAP = {"core22": "qt-framework-sdk"}
+
+
+@dataclasses.dataclass
+class ExtensionInfo:
+    """Content/SDK build information."""
+
+    cmake_args: list
+
+
+@dataclasses.dataclass
+class QTSnaps:
+    """A structure of QT related snaps."""
+
+    sdk: str
+    content: str
+    builtin: bool = True
+
+
+class QTFramework(Extension):
+    r"""The QT Framework extension.
+
+    This extension makes it easy to assemble QT based applications.
+
+    It configures each application with the following plugs:
+
+    \b
+    - Common Icon Themes.
+    - Common Sound Themes.
+    - The QT Frameworks runtime libraries and utilities.
+
+    For easier desktop integration, it also configures each application
+    entry with these additional plugs:
+
+    \b
+    - desktop (https://snapcraft.io/docs/desktop-interface)
+    - desktop-legacy (https://snapcraft.io/docs/desktop-legacy-interface)
+    - opengl (https://snapcraft.io/docs/opengl-interface)
+    - wayland (https://snapcraft.io/docs/wayland-interface)
+    - x11 (https://snapcraft.io/docs/x11-interface)
+    """
+
+    @staticmethod
+    @overrides
+    def get_supported_bases() -> Tuple[str, ...]:
+        return ("core22",)
+
+    @staticmethod
+    @overrides
+    def get_supported_confinement() -> Tuple[str, ...]:
+        return "strict", "devmode"
+
+    @staticmethod
+    @overrides
+    def is_experimental(base: Optional[str]) -> bool:
+        return False
+
+    @overrides
+    def get_app_snippet(self) -> Dict[str, Any]:
+        return {
+            "command-chain": ["snap/command-chain/desktop-launch"],
+            "plugs": ["desktop", "desktop-legacy", "opengl", "wayland", "x11"],
+        }
+
+    @functools.cached_property
+    def qt_snaps(self) -> QTSnaps:
+        """Return the QT related snaps to use to construct the environment."""
+        base = self.yaml_data["base"]
+        sdk_snap = _SDK_SNAP[base]
+
+        build_snaps: List[str] = []
+        for part in self.yaml_data["parts"].values():
+            build_snaps.extend(part.get("build-snaps", []))
+
+        builtin = True
+
+        for snap in build_snaps:
+            if sdk_snap == snap.split('/')[0]:
+                builtin = False
+                break
+
+        # The same except the trailing -sd
+        content = sdk_snap[:-4]
+
+        return QTSnaps(sdk=sdk_snap, content=content, builtin=builtin)
+
+    @functools.cached_property
+    def ext_info(self) -> ExtensionInfo:
+        """Return the extension info cmake_args, provider, content, build_snaps."""
+        prefix_root = f"/snap/{self.qt_snaps.sdk}/current/opt/"
+        cmake_args = [
+            f"-DCMAKE_FIND_ROOT_PATH=/snap/{self.qt_snaps.sdk}/current",
+            f"-DCMAKE_PREFIX_PATH={prefix_root}/qt6-5;{prefix_root}/qt6-4;{prefix_root}/qt6-2;{prefix_root}/qt5-15",
+            # f"-DQt6_DIR=/snap/{self.qt_snaps.sdk}/current/opt/qt6-2/lib/cmake/Qt6"
+            "-DZLIB_INCLUDE_DIR=/lib/x86_64-linux-gnu"
+            ]
+
+        return ExtensionInfo(cmake_args=cmake_args)
+
+    @overrides
+    def get_root_snippet(self) -> Dict[str, Any]:
+        platform_snap = self.qt_snaps.content
+        content_snap = self.qt_snaps.content + "-all"
+
+        return {
+            "assumes": ["snapd2.43"],  # for 'snapctl is-connected'
+            "compression": "lzo",
+            "plugs": {
+                "desktop": {"mount-host-font-cache": False},
+                "icon-themes": {
+                    "interface": "content",
+                    "target": "$SNAP/data-dir/icons",
+                    "default-provider": "gtk-common-themes",
+                },
+                "sound-themes": {
+                    "interface": "content",
+                    "target": "$SNAP/data-dir/sounds",
+                    "default-provider": "gtk-common-themes",
+                },
+                platform_snap: {
+                    "content": content_snap.split('/')[0],
+                    "interface": "content",
+                    "default-provider": platform_snap,
+                    "target": "$SNAP/qt-framework",
+                },
+            },
+            "environment": {"SNAP_DESKTOP_RUNTIME": "$SNAP/qt-framework"},
+            "hooks": {
+                "configure": {
+                    "plugs": ["desktop"],
+                    "command-chain": ["snap/command-chain/hooks-configure-fonts"],
+                }
+            },
+            "layout": {"/usr/share/X11": {"symlink": "$SNAP/qt-framework/usr/share/X11"}},
+        }
+
+    @overrides
+    def get_part_snippet(self, *, plugin_name: str) -> Dict[str, Any]:
+        sdk_snap = self.qt_snaps.sdk
+        cmake_args = self.ext_info.cmake_args
+
+        return {
+            "build-environment": [
+                {
+                    "PATH": prepend_to_env(
+                        "PATH", [f"/snap/{sdk_snap}/current/usr/bin"]
+                    ),
+                },
+                {
+                    "XDG_DATA_DIRS": prepend_to_env(
+                        "XDG_DATA_DIRS",
+                        [
+                            f"$CRAFT_STAGE/usr/share:/snap/{sdk_snap}/current/usr/share",
+                            "/usr/share",
+                        ],
+                    ),
+                },
+                {
+                    "SNAPCRAFT_CMAKE_ARGS": prepend_to_env(
+                        "SNAPCRAFT_CMAKE_ARGS", cmake_args
+                    ),
+                },
+            ],
+            "build-packages": [
+                "libgl1-mesa-dev",
+            ]
+        }
+
+    @overrides
+    def get_parts_snippet(self) -> Dict[str, Any]:
+        # We can change this to the lightweight command-chain when
+        # the content snap includes the desktop-launch from
+        # https://github.com/snapcore/snapcraft-desktop-integration
+        source = get_extensions_data_dir() / "desktop" / "command-chain"
+
+        if self.qt_snaps.builtin:
+            return {
+                "qt-framework/sdk": {
+                    "source": str(source),
+                    "plugin": "make",
+                    "make-parameters": [f"PLATFORM_PLUG={self.qt_snaps.content}"],
+                    "build-snaps": [self.qt_snaps.sdk],
+                },
+            }
+
+        return {
+            "qt-framework/sdk": {
+                "source": str(source),
+                "plugin": "make",
+                "make-parameters": [f"PLATFORM_PLUG={self.qt_snaps.content}"],
+            },
+        }

snapcraft/extensions/registry.py

@@ -22,6 +22,7 @@
 
 from .gnome import GNOME
 from .kde_neon import KDENeon
+from .qt_framework import QTFramework
 from .ros2_humble import ROS2HumbleExtension
 
 if TYPE_CHECKING:
@@ -33,6 +34,7 @@
     "gnome": GNOME,
     "ros2-humble": ROS2HumbleExtension,
     "kde-neon": KDENeon,
+    "qt-framework": QTFramework,
 }