new: Add custom PEP517 build backend

8 files changed, 289 insertions, 222 deletions

diff --git a/MANIFEST.in b/MANIFEST.in
index 91460f387..b5c91eebc 100644
--- a/MANIFEST.in
+++ b/MANIFEST.in
@@ -1,4 +1,7 @@
 include COPYING
+include ChangeLog
+recursive-include pep517build *
 recursive-include po *
 recursive-include data *.1 *.in
 recursive-include test *
+prune */__pycache__
diff --git a/README.md b/README.md
index f3fe21bd6..75d5137de 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,6 @@
-# Welcome to Gajim
+[[_TOC_]]
+
+## Requirements
 
 ### Runtime Requirements
 
@@ -39,19 +41,67 @@
 - [gst-plugins-ugly](https://gitlab.freedesktop.org/gstreamer/gst-plugins-ugly)
 - [gst-libav](https://gitlab.freedesktop.org/gstreamer/gst-libav)
 
-### Install Requirements
+### Build Requirements
 
 - [setuptools](https://pypi.org/project/setuptools/) (>=65.0.0)
 - [gettext](https://savannah.gnu.org/projects/gettext/)
 
-### Running Tests
+To build Gajim a PEP517 build frontend like pip (https://pip.pypa.io/en/stable/) or build (https://pypa-build.readthedocs.io/en/stable/) must be used.
+
+The build frontend takes care of installing all python build requirements. Beware `gettext` is not a python library and cannot be installed by the build frontend.
+
+## Building
+
+### Building the metadata files (Unix only)
+
+```bash
+./pep517build/build_metadata.py -o dist/metadata
+```
+
+### Building the wheel
+
+This is only necessary if you need the wheel, otherwise you can skip to the Installing section.
+
+#### Using `build`
+
+```bash
+python -m build -w
+```
+
+#### Using `pip`
+
+```bash
+pip wheel --no-deps --use-pep517 -w dist .
+```
+
+## Installing
+
+### Installing with `pip`
+
+```bash
+pip install .
+```
+
+### Installing the wheel
+
+```bash
+pip install dist/name_of_wheel.whl
+```
+
+### Installing the metadata files (Unix only)
+
+```bash
+./pep517build/install_metadata.py dist/metadata --prefix=/usr
+```
+
+## Tests
 
 - `python -m unittest discover -s test`
 - `python -m unittest ./test/dialogs/gui_file.py` (for testing GUI files)
 
-### Installation Procedure
+## Packages and install instructions
 
-#### Packages
+### Packages
 
 - [Arch Linux](https://www.archlinux.org/packages/community/any/gajim/)
 - [Debian](https://packages.debian.org/stable/gajim)
@@ -59,24 +109,20 @@
 - [Ubuntu](https://packages.ubuntu.com/gajim)
 - [FreeBSD](https://www.freshports.org/net-im/gajim/)
 
-#### Flatpak
+### Flatpak
 
 see [README](./flatpak/README.md)
 
-#### Snapshots
+### Snapshots
 
 - [Daily Linux](https://www.gajim.org/downloads/snap/)
 - [Daily Windows](https://gajim.org/downloads/snap/win)
 
-#### Linux
-
-    pip install .
-
-#### Mac
+### Mac
 
 see [Wiki](https://dev.gajim.org/gajim/gajim/-/wikis/help/Gajim-on-macOS)
 
-#### Developing
+## Developing
 
 To create a virtualenv you can execute
 
@@ -89,17 +135,17 @@ Afterwards activate the virtual environment with
     source .venv/bin/activate
     ./launch.py
 
-#### Windows
+### Windows
 
 see [README](./win/README.md)
 
-### Miscellaneous
+## Miscellaneous
 
-#### Debugging
+### Debugging
 
 Execute gajim with `--verbose`
 
-#### Links
+### Links
 
 - [FAQ](https://dev.gajim.org/gajim/gajim/wikis/help/gajimfaq)
 - [Wiki](https://dev.gajim.org/gajim/gajim/wikis/home)
diff --git a/pep517build/__init__.py b/pep517build/__init__.py
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/pep517build/__init__.py
diff --git a/pep517build/backend.py b/pep517build/backend.py
new file mode 100644
index 000000000..1592ccb57
--- /dev/null
+++ b/pep517build/backend.py
@@ -0,0 +1,89 @@
+from __future__ import annotations
+
+from typing import Any
+
+import logging
+import subprocess
+from pathlib import Path
+
+import setuptools.build_meta as _orig
+
+logging.basicConfig(level='INFO', format='%(message)s')
+
+ALLOWED_CONFIG_SETTINGS = {'target'}
+MAN_FILES = [
+    Path('data/gajim.1'),
+    Path('data/gajim-remote.1')
+]
+META_FILES = [
+    (Path('data/org.gajim.Gajim.desktop.in'), '--desktop'),
+    (Path('data/org.gajim.Gajim.appdata.xml.in'), '--xml')
+]
+ICONS = [
+    Path('gajim/data/icons/hicolor/scalable/apps/org.gajim.Gajim.svg'),
+    Path('gajim/data/icons/hicolor/scalable/apps/org.gajim.Gajim-symbolic.svg'),
+]
+
+
+def build_translations() -> None:
+    # Compile translation files and place them into "gajim/data/locale"
+
+    source_dir = Path.cwd()
+    translation_dir = source_dir / 'po'
+    locale_dir = source_dir / 'gajim' / 'data' / 'locale'
+
+    langs = sorted([lang.stem for lang in translation_dir.glob('*.po')])
+
+    for lang in langs:
+        po_file = source_dir / 'po' / f'{lang}.po'
+        mo_file = locale_dir / lang / 'LC_MESSAGES' / 'gajim.mo'
+        mo_file.parent.mkdir(parents=True, exist_ok=True)
+
+        logging.info('Compile %s >> %s', po_file, mo_file)
+
+        subprocess.run(['msgfmt',
+                        str(po_file),
+                        '-o',
+                        str(mo_file)],
+                       check=True)
+
+
+def _check_config_settings(config_settings: dict[str, str]) -> None:
+    settings = set(config_settings.keys()) - ALLOWED_CONFIG_SETTINGS
+    if settings:
+        raise ValueError('Unknown config setting %s' % settings)
+
+
+def get_requires_for_build_sdist(*args: Any, **kwargs: Any) -> str:
+    return _orig.get_requires_for_build_sdist(*args, **kwargs)
+
+
+def build_sdist(*args: Any, **kwargs: Any) -> str:
+    return _orig.build_sdist(*args, **kwargs)
+
+
+def get_requires_for_build_wheel(*args: Any, **kwargs: Any) -> str:
+    return _orig.get_requires_for_build_wheel(*args, **kwargs)
+
+
+def prepare_metadata_for_build_wheel(*args: Any, **kwargs: Any) -> str:
+    return _orig.prepare_metadata_for_build_wheel(*args, **kwargs)
+
+
+def build_wheel(wheel_directory: str,
+                config_settings: dict[str, str] | None = None,
+                metadata_directory: str | None = None
+                ) -> str:
+
+    if config_settings is not None:
+        _check_config_settings(config_settings)
+
+    build_translations()
+
+    basename = _orig.build_wheel(
+        wheel_directory,
+        config_settings=config_settings,
+        metadata_directory=metadata_directory,
+    )
+
+    return basename
diff --git a/pep517build/build_metadata.py b/pep517build/build_metadata.py
new file mode 100755
index 000000000..7e7d53f4b
--- /dev/null
+++ b/pep517build/build_metadata.py
@@ -0,0 +1,85 @@
+#!/usr/bin/env python3
+
+from __future__ import annotations
+
+import argparse
+import gzip
+import logging
+import shutil
+import subprocess
+from pathlib import Path
+
+logging.basicConfig(level='INFO', format='%(message)s')
+
+DEFAULT_METADATA_PATH = Path('dist/metadata')
+
+MAN_FILES = [
+    Path('data/gajim.1'),
+    Path('data/gajim-remote.1')
+]
+META_FILES = [
+    (Path('data/org.gajim.Gajim.desktop.in'), '--desktop'),
+    (Path('data/org.gajim.Gajim.appdata.xml.in'), '--xml')
+]
+ICONS = [
+    Path('gajim/data/icons/hicolor/scalable/apps/org.gajim.Gajim.svg'),
+    Path('gajim/data/icons/hicolor/scalable/apps/org.gajim.Gajim-symbolic.svg'),
+]
+
+
+def build_man(target_path: Path) -> None:
+    # Build man files in target path
+
+    for man_path in MAN_FILES:
+        data = man_path.read_bytes()
+        man_file_name = man_path.name
+
+        man_out_path = target_path / f'{man_file_name}.gz'
+        logging.info('Compress %s >> %s', man_file_name, man_out_path)
+
+        with gzip.open(man_out_path, 'wb') as f_out:
+            f_out.write(data)
+
+
+
+def build_intl(target_path: Path) -> None:
+    # Merge translation files into desktop and metadata files
+
+    for file_path, option in META_FILES:
+        out_path = target_path / file_path.name
+        out_path = out_path.with_suffix('')
+
+        logging.info('Compile %s >> %s', file_path, out_path)
+
+        subprocess.run(['msgfmt',
+                        option,
+                        '-d',
+                        'po',
+                        '--template',
+                        str(file_path),
+                        '-o',
+                        str(out_path)],
+                        check=True)
+
+
+def build_app_icons(target_path: Path) -> None:
+    for file_path in ICONS:
+        out_path = target_path / file_path.name
+
+        logging.info('Copy %s >> %s', file_path, out_path)
+        shutil.copy2(file_path, out_path)
+
+
+if __name__ == '__main__':
+    parser = argparse.ArgumentParser(description='Build metadata files')
+    parser.add_argument('-o',
+                        '--output-dir',
+                        type=Path,
+                        default=DEFAULT_METADATA_PATH)
+    args = parser.parse_args()
+
+    args.output_dir.mkdir(parents=True, exist_ok=True)
+
+    build_man(args.output_dir)
+    build_intl(args.output_dir)
+    build_app_icons(args.output_dir)
diff --git a/pep517build/install_metadata.py b/pep517build/install_metadata.py
new file mode 100755
index 000000000..17a5a2104
--- /dev/null
+++ b/pep517build/install_metadata.py
@@ -0,0 +1,43 @@
+#!/usr/bin/env python3
+
+from __future__ import annotations
+
+import argparse
+import logging
+import shutil
+from pathlib import Path
+
+logging.basicConfig(level='INFO', format='%(message)s')
+
+DEFAULT_METADATA_PATH = Path('dist/metadata')
+
+FILES = {
+    'gajim-remote.1.gz': 'share/man/man1',
+    'gajim.1.gz': 'share/man/man1',
+    'org.gajim.Gajim.desktop': 'share/applications',
+    'org.gajim.Gajim-symbolic.svg': 'share/icons/hicolor/scalable/apps',
+    'org.gajim.Gajim.svg': 'share/icons/hicolor/scalable/apps',
+    'org.gajim.Gajim.appdata.xml': 'share/metainfo',
+}
+
+if __name__ == '__main__':
+    parser = argparse.ArgumentParser(description='Install metadata files')
+    parser.add_argument('input',
+                        type=Path,
+                        default=DEFAULT_METADATA_PATH,
+                        help='Path to the metadata folder, '
+                             'default: dist/metadata')
+    parser.add_argument('--prefix',
+                        type=Path,
+                        required=True,
+                        help='The path prefix, for example "/usr"')
+
+    args = parser.parse_args()
+
+    for file, path in FILES.items():
+        src = args.input / file
+        dest_dir = args.prefix / path
+        logging.info('Copy %s to %s', src, dest_dir)
+        if not dest_dir.exists():
+            dest_dir.mkdir(parents=True)
+        shutil.copy(src, dest_dir / file)
diff --git a/pyproject.toml b/pyproject.toml
index 09daf3287..1b1dfebb1 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -2,7 +2,8 @@
 requires = [
   "setuptools >= 65.0.0",
 ]
-build-backend = "setuptools.build_meta"
+build-backend = "backend"
+backend-path = ["pep517build"]
 
 [project]
 name = "gajim"
@@ -56,25 +57,18 @@ gajim-remote = "gajim.gajim_remote:main"
 [project.gui-scripts]
 gajim = "gajim.gajim:main"
 
-[tool.setuptools]
-include-package-data = true
-
 [tool.setuptools.packages.find]
 include = ["gajim*"]
-# Necessary so gajim.data is recogniced as namespace package and all files
-# under it are included as package-data
-namespaces = true
 
 [tool.setuptools.package-data]
-"gajim.data" = [
-  "icons/**/index.theme",
-]
+gajim = ["py.typed"]
+"gajim.data" = ["**/*"]
 
 [tool.setuptools.dynamic]
 version = {attr = "gajim.__version__"}
 
 [tool.codespell]
-skip = "*__pycache__*,build,test,*.egg-info,.git,*.po,*.nsi,*.spec"
+skip = "*__pycache__*,build,dist,test,*.egg-info,.git,*.po,*.nsi,*.spec"
 ignore-words-list = "claus,pres,ser,trough"
 
 [tool.pyright]
@@ -113,6 +107,7 @@ include = [
     "mac/*",
     "scripts/*",
     "win/*",
+    "pep517build/*",
     "gajim/common/application.py",
     "gajim/common/call_manager.py",
     "gajim/common/cert_store.py",
diff --git a/setup.py b/setup.py
deleted file mode 100755
index 0cb78c633..000000000
--- a/setup.py
+++ /dev/null
@@ -1,194 +0,0 @@
-#!/usr/bin/env python3
-
-from __future__ import annotations
-
-from typing import cast
-
-import logging
-import os
-import sys
-
-if sys.version_info < (3, 10):
-    sys.exit('Gajim needs Python 3.10+')
-
-import subprocess
-from pathlib import Path
-
-from setuptools import setup
-from setuptools.command.build_py import build_py as _build
-from setuptools.command.install import install as _install
-
-DataFilesT = list[tuple[str, list[str]]]
-
-
-MAN_FILES = [
-    'gajim.1',
-    'gajim-remote.1'
-]
-META_FILES = [
-    ('data/org.gajim.Gajim.desktop', 'share/applications', '--desktop'),
-    ('data/org.gajim.Gajim.appdata.xml', 'share/metainfo', '--xml')]
-
-
-TRANS_DIR = Path('po')
-TRANS_TEMPLATE = TRANS_DIR / 'gajim.pot'
-REPO_DIR = Path(__file__).resolve().parent
-BUILD_DIR = REPO_DIR / 'build'
-
-ALL_LINGUAS = sorted([lang.stem for lang in TRANS_DIR.glob('*.po')])
-
-
-logging.basicConfig(level='INFO', format='%(levelname)s: %(message)s')
-log = logging.getLogger()
-
-
-def newer(source: Path, target: Path) -> bool:
-    if not source.exists():
-        raise ValueError('file "%s" does not exist' % source.resolve())
-    if not target.exists():
-        return True
-
-    from stat import ST_MTIME
-    mtime1 = source.stat()[ST_MTIME]
-    mtime2 = target.stat()[ST_MTIME]
-
-    return mtime1 > mtime2
-
-
-def build_translation() -> None:
-    for lang in ALL_LINGUAS:
-        po_file = TRANS_DIR / f'{lang}.po'
-        mo_file = BUILD_DIR / 'mo' / lang / 'LC_MESSAGES' / 'gajim.mo'
-        mo_dir = mo_file.parent
-        if not (mo_dir.is_dir() or mo_dir.is_symlink()):
-            mo_dir.mkdir(parents=True)
-
-        if newer(po_file, mo_file):
-            subprocess.run(['msgfmt',
-                            str(po_file),
-                            '-o',
-                            str(mo_file)],
-                           cwd=REPO_DIR,
-                           check=True)
-
-            log.info('Compiling %s >> %s', po_file, mo_file)
-
-
-def install_trans(data_files: DataFilesT) -> None:
-    for lang in ALL_LINGUAS:
-        mo_file = str(BUILD_DIR / 'mo' / lang / 'LC_MESSAGES' / 'gajim.mo')
-        target = f'share/locale/{lang}/LC_MESSAGES'
-        data_files.append((target, [mo_file]))
-
-
-def build_man() -> None:
-    '''
-    Compress Gajim manual files
-    '''
-    newdir = BUILD_DIR / 'man'
-    if not (newdir.is_dir() or newdir.is_symlink()):
-        newdir.mkdir()
-
-    for man in MAN_FILES:
-        filename = Path('data') / man
-        man_file_gz = newdir / (man + '.gz')
-        if man_file_gz.exists():
-            if newer(filename, man_file_gz):
-                man_file_gz.unlink()
-            else:
-                continue
-
-        import gzip
-
-        # Binary io, so open is OK
-        with open(filename, 'rb') as f_in,\
-                gzip.open(man_file_gz, 'wb') as f_out:
-            f_out.writelines(f_in)
-            log.info('Compiling %s >> %s', filename, man_file_gz)
-
-
-def install_man(data_files: DataFilesT) -> None:
-    man_dir = BUILD_DIR / 'man'
-    target = 'share/man/man1'
-
-    for man in MAN_FILES:
-        man_file_gz = str(man_dir / (man + '.gz'))
-        data_files.append((target, [man_file_gz]))
-
-
-def build_intl() -> None:
-    '''
-    Merge translation files into desktop and mime files
-    '''
-    base = BUILD_DIR
-
-    for filename, _, option in META_FILES:
-        newfile = base / filename
-        newdir = newfile.parent
-        if not (newdir.is_dir() or newdir.is_symlink()):
-            newdir.mkdir()
-        merge(Path(filename + '.in'), newfile, option)
-
-
-def install_intl(data_files: DataFilesT) -> None:
-    for filename, target, _ in META_FILES:
-        data_files.append((target, [str(BUILD_DIR / filename)]))
-
-
-def merge(in_file: Path,
-          out_file: Path,
-          option: str,
-          po_dir: str = 'po') -> None:
-    '''
-    Run the msgfmt command.
-    '''
-    if in_file.exists():
-        cmd = (('msgfmt %(opt)s -d %(po_dir)s --template %(in_file)s '
-                '-o %(out_file)s') %
-               {'opt': option,
-                'po_dir': po_dir,
-                'in_file': in_file,
-                'out_file': out_file})
-        if os.system(cmd) != 0:
-            msg = ('ERROR: %s was not merged into the translation files!\n' %
-                   out_file)
-            raise SystemExit(msg)
-        log.info('Compiling %s >> %s', in_file, out_file)
-
-
-class Build(_build):
-    def run(self):
-        build_translation()
-        if sys.platform != 'win32':
-            build_man()
-            build_intl()
-        _build.run(self)
-
-
-class Install(_install):
-    def run(self):
-        data_files = cast(DataFilesT, self.distribution.data_files)  # pyright: ignore  # noqa: E501
-        install_trans(data_files)
-        if sys.platform != 'win32':
-            install_man(data_files)
-            install_intl(data_files)
-        _install.run(self)  # pyright: ignore
-
-
-# only install subdirectories of data
-data_files_app_icon = [
-    ('share/icons/hicolor/scalable/apps',
-     ['gajim/data/icons/hicolor/scalable/apps/org.gajim.Gajim.svg']),
-    ('share/icons/hicolor/scalable/apps',
-     ['gajim/data/icons/hicolor/scalable/apps/org.gajim.Gajim-symbolic.svg'])
-]
-
-data_files: DataFilesT = data_files_app_icon
-
-setup(
-    cmdclass={
-        'build_py': Build,
-        'install': Install,
-    },
-    data_files=data_files
-)