packaging: isolate invocation of WiX to own function

Like we did for Inno, we want to split out the building
of Mercurial from invoking the packaging tool so that we
can introduce an alternate build mechanism.

As part of this refactor, there are inconsequential changes
to file layouts. Before, some shared files such as the
WiX binaries and merge modules would be installed under
build/. Now, they are installed under build/wix-*. This
is to keep implementation simpler. But it also helps keep
build state more isolated.

Differential Revision: https://phab.mercurial-scm.org/D8474

contrib/packaging/hgpackaging/wix.py

@@ -1,499 +1,526 b''
 # wix.py - WiX installer functionality
 #
 # Copyright 2019 Gregory Szorc <[e-mail]>
 #
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2 or any later version.
 
 # no-check-code because Python 3 native.
 
 import collections
 import os
 import pathlib
 import re
 import shutil
 import subprocess
 import typing
 import uuid
 import xml.dom.minidom
 
 from .downloads import download_entry
 from .py2exe import (
     build_py2exe,
     stage_install,
 )
 from .util import (
     extract_zip_to_directory,
     normalize_windows_version,
     process_install_rules,
     sign_with_signtool,
 )
 
 
 EXTRA_PACKAGES = {
     'dulwich',
     'distutils',
     'keyring',
     'pygments',
     'win32ctypes',
 }
 
 
 EXTRA_INSTALL_RULES = [
     ('contrib/packaging/wix/COPYING.rtf', 'COPYING.rtf'),
     ('contrib/win32/mercurial.ini', 'defaultrc/mercurial.rc'),
 ]
 
 STAGING_REMOVE_FILES = [
     # We use the RTF variant.
     'copying.txt',
 ]
 
 SHORTCUTS = {
     # hg.1.html'
     'hg.file.5d3e441c_28d9_5542_afd0_cdd4234f12d5': {
         'Name': 'Mercurial Command Reference',
     },
     # hgignore.5.html
     'hg.file.5757d8e0_f207_5e10_a2ec_3ba0a062f431': {
         'Name': 'Mercurial Ignore Files',
     },
     # hgrc.5.html
     'hg.file.92e605fd_1d1a_5dc6_9fc0_5d2998eb8f5e': {
         'Name': 'Mercurial Configuration Files',
     },
 }
 
 
 def find_version(source_dir: pathlib.Path):
     version_py = source_dir / 'mercurial' / '__version__.py'
 
     with version_py.open('r', encoding='utf-8') as fh:
         source = fh.read().strip()
 
     m = re.search('version = b"(.*)"', source)
     return m.group(1)
 
 
 def ensure_vc90_merge_modules(build_dir):
     x86 = (
         download_entry(
             'vc9-crt-x86-msm',
             build_dir,
             local_name='microsoft.vcxx.crt.x86_msm.msm',
         )[0],
         download_entry(
             'vc9-crt-x86-msm-policy',
             build_dir,
             local_name='policy.x.xx.microsoft.vcxx.crt.x86_msm.msm',
         )[0],
     )
 
     x64 = (
         download_entry(
             'vc9-crt-x64-msm',
             build_dir,
             local_name='microsoft.vcxx.crt.x64_msm.msm',
         )[0],
         download_entry(
             'vc9-crt-x64-msm-policy',
             build_dir,
             local_name='policy.x.xx.microsoft.vcxx.crt.x64_msm.msm',
         )[0],
     )
     return {
         'x86': x86,
         'x64': x64,
     }
 
 
 def run_candle(wix, cwd, wxs, source_dir, defines=None):
     args = [
         str(wix / 'candle.exe'),
         '-nologo',
         str(wxs),
         '-dSourceDir=%s' % source_dir,
     ]
 
     if defines:
         args.extend('-d%s=%s' % define for define in sorted(defines.items()))
 
     subprocess.run(args, cwd=str(cwd), check=True)
 
 
 def make_post_build_signing_fn(
     name,
     subject_name=None,
     cert_path=None,
     cert_password=None,
     timestamp_url=None,
 ):
     """Create a callable that will use signtool to sign hg.exe."""
 
     def post_build_sign(source_dir, build_dir, dist_dir, version):
         description = '%s %s' % (name, version)
 
         sign_with_signtool(
             dist_dir / 'hg.exe',
             description,
             subject_name=subject_name,
             cert_path=cert_path,
             cert_password=cert_password,
             timestamp_url=timestamp_url,
         )
 
     return post_build_sign
 
 
 def make_files_xml(staging_dir: pathlib.Path, is_x64) -> str:
     """Create XML string listing every file to be installed."""
 
     # We derive GUIDs from a deterministic file path identifier.
     # We shoehorn the name into something that looks like a URL because
     # the UUID namespaces are supposed to work that way (even though
     # the input data probably is never validated).
 
     doc = xml.dom.minidom.parseString(
         '<?xml version="1.0" encoding="utf-8"?>'
         '<Wix xmlns="http://schemas.microsoft.com/wix/2006/wi">'
         '</Wix>'
     )
 
     # Assemble the install layout by directory. This makes it easier to
     # emit XML, since each directory has separate entities.
     manifest = collections.defaultdict(dict)
 
     for root, dirs, files in os.walk(staging_dir):
         dirs.sort()
 
         root = pathlib.Path(root)
         rel_dir = root.relative_to(staging_dir)
 
         for i in range(len(rel_dir.parts)):
             parent = '/'.join(rel_dir.parts[0 : i + 1])
             manifest.setdefault(parent, {})
 
         for f in sorted(files):
             full = root / f
             manifest[str(rel_dir).replace('\\', '/')][full.name] = full
 
     component_groups = collections.defaultdict(list)
 
     # Now emit a <Fragment> for each directory.
     # Each directory is composed of a <DirectoryRef> pointing to its parent
     # and defines child <Directory>'s and a <Component> with all the files.
     for dir_name, entries in sorted(manifest.items()):
         # The directory id is derived from the path. But the root directory
         # is special.
         if dir_name == '.':
             parent_directory_id = 'INSTALLDIR'
         else:
             parent_directory_id = 'hg.dir.%s' % dir_name.replace('/', '.')
 
         fragment = doc.createElement('Fragment')
         directory_ref = doc.createElement('DirectoryRef')
         directory_ref.setAttribute('Id', parent_directory_id)
 
         # Add <Directory> entries for immediate children directories.
         for possible_child in sorted(manifest.keys()):
             if (
                 dir_name == '.'
                 and '/' not in possible_child
                 and possible_child != '.'
             ):
                 child_directory_id = 'hg.dir.%s' % possible_child
                 name = possible_child
             else:
                 if not possible_child.startswith('%s/' % dir_name):
                     continue
                 name = possible_child[len(dir_name) + 1 :]
                 if '/' in name:
                     continue
 
                 child_directory_id = 'hg.dir.%s' % possible_child.replace(
                     '/', '.'
                 )
 
             directory = doc.createElement('Directory')
             directory.setAttribute('Id', child_directory_id)
             directory.setAttribute('Name', name)
             directory_ref.appendChild(directory)
 
         # Add <Component>s for files in this directory.
         for rel, source_path in sorted(entries.items()):
             if dir_name == '.':
                 full_rel = rel
             else:
                 full_rel = '%s/%s' % (dir_name, rel)
 
             component_unique_id = (
                 'https://www.mercurial-scm.org/wix-installer/0/component/%s'
                 % full_rel
             )
             component_guid = uuid.uuid5(uuid.NAMESPACE_URL, component_unique_id)
             component_id = 'hg.component.%s' % str(component_guid).replace(
                 '-', '_'
             )
 
             component = doc.createElement('Component')
 
             component.setAttribute('Id', component_id)
             component.setAttribute('Guid', str(component_guid).upper())
             component.setAttribute('Win64', 'yes' if is_x64 else 'no')
 
             # Assign this component to a top-level group.
             if dir_name == '.':
                 component_groups['ROOT'].append(component_id)
             elif '/' in dir_name:
                 component_groups[dir_name[0 : dir_name.index('/')]].append(
                     component_id
                 )
             else:
                 component_groups[dir_name].append(component_id)
 
             unique_id = (
                 'https://www.mercurial-scm.org/wix-installer/0/%s' % full_rel
             )
             file_guid = uuid.uuid5(uuid.NAMESPACE_URL, unique_id)
 
             # IDs have length limits. So use GUID to derive them.
             file_guid_normalized = str(file_guid).replace('-', '_')
             file_id = 'hg.file.%s' % file_guid_normalized
 
             file_element = doc.createElement('File')
             file_element.setAttribute('Id', file_id)
             file_element.setAttribute('Source', str(source_path))
             file_element.setAttribute('KeyPath', 'yes')
             file_element.setAttribute('ReadOnly', 'yes')
 
             component.appendChild(file_element)
             directory_ref.appendChild(component)
 
         fragment.appendChild(directory_ref)
         doc.documentElement.appendChild(fragment)
 
     for group, component_ids in sorted(component_groups.items()):
         fragment = doc.createElement('Fragment')
         component_group = doc.createElement('ComponentGroup')
         component_group.setAttribute('Id', 'hg.group.%s' % group)
 
         for component_id in component_ids:
             component_ref = doc.createElement('ComponentRef')
             component_ref.setAttribute('Id', component_id)
             component_group.appendChild(component_ref)
 
         fragment.appendChild(component_group)
         doc.documentElement.appendChild(fragment)
 
     # Add <Shortcut> to files that have it defined.
     for file_id, metadata in sorted(SHORTCUTS.items()):
         els = doc.getElementsByTagName('File')
         els = [el for el in els if el.getAttribute('Id') == file_id]
 
         if not els:
             raise Exception('could not find File[Id=%s]' % file_id)
 
         for el in els:
             shortcut = doc.createElement('Shortcut')
             shortcut.setAttribute('Id', 'hg.shortcut.%s' % file_id)
             shortcut.setAttribute('Directory', 'ProgramMenuDir')
             shortcut.setAttribute('Icon', 'hgIcon.ico')
             shortcut.setAttribute('IconIndex', '0')
             shortcut.setAttribute('Advertise', 'yes')
             for k, v in sorted(metadata.items()):
                 shortcut.setAttribute(k, v)
 
             el.appendChild(shortcut)
 
     return doc.toprettyxml()
 
 
 def build_installer(
     source_dir: pathlib.Path,
     python_exe: pathlib.Path,
     msi_name='mercurial',
     version=None,
     post_build_fn=None,
     extra_packages_script=None,
     extra_wxs: typing.Optional[typing.Dict[str, str]] = None,
     extra_features: typing.Optional[typing.List[str]] = None,
 ):
     """Build a WiX MSI installer.
 
     ``source_dir`` is the path to the Mercurial source tree to use.
     ``arch`` is the target architecture. either ``x86`` or ``x64``.
     ``python_exe`` is the path to the Python executable to use/bundle.
     ``version`` is the Mercurial version string. If not defined,
     ``mercurial/__version__.py`` will be consulted.
     ``post_build_fn`` is a callable that will be called after building
     Mercurial but before invoking WiX. It can be used to e.g. facilitate
     signing. It is passed the paths to the Mercurial source, build, and
     dist directories and the resolved Mercurial version.
     ``extra_packages_script`` is a command to be run to inject extra packages
     into the py2exe binary. It should stage packages into the virtualenv and
     print a null byte followed by a newline-separated list of packages that
     should be included in the exe.
     ``extra_wxs`` is a dict of {wxs_name: working_dir_for_wxs_build}.
     ``extra_features`` is a list of additional named Features to include in
     the build. These must match Feature names in one of the wxs scripts.
     """
     arch = 'x64' if r'\x64' in os.environ.get('LIB', '') else 'x86'
 
     hg_build_dir = source_dir / 'build'
     dist_dir = source_dir / 'dist'
-    wix_dir = source_dir / 'contrib' / 'packaging' / 'wix'
 
     requirements_txt = (
         source_dir / 'contrib' / 'packaging' / 'requirements_win32.txt'
     )
 
     build_py2exe(
         source_dir,
         hg_build_dir,
         python_exe,
         'wix',
         requirements_txt,
         extra_packages=EXTRA_PACKAGES,
         extra_packages_script=extra_packages_script,
     )
 
     orig_version = version or find_version(source_dir)
     version = normalize_windows_version(orig_version)
     print('using version string: %s' % version)
     if version != orig_version:
         print('(normalized from: %s)' % orig_version)
 
     if post_build_fn:
         post_build_fn(source_dir, hg_build_dir, dist_dir, version)
 
     build_dir = hg_build_dir / ('wix-%s' % arch)
     staging_dir = build_dir / 'stage'
 
     build_dir.mkdir(exist_ok=True)
 
     # Purge the staging directory for every build so packaging is pristine.
     if staging_dir.exists():
         print('purging %s' % staging_dir)
         shutil.rmtree(staging_dir)
 
     stage_install(source_dir, staging_dir, lower_case=True)
 
     # We also install some extra files.
     process_install_rules(EXTRA_INSTALL_RULES, source_dir, staging_dir)
 
     # And remove some files we don't want.
     for f in STAGING_REMOVE_FILES:
         p = staging_dir / f
         if p.exists():
             print('removing %s' % p)
             p.unlink()
 
-    wix_pkg, wix_entry = download_entry('wix', hg_build_dir)
-    wix_path = hg_build_dir / ('wix-%s' % wix_entry['version'])
+    return run_wix_packaging(
+        source_dir,
+        build_dir,
+        staging_dir,
+        arch,
+        version=version,
+        orig_version=orig_version,
+        msi_name=msi_name,
+        extra_wxs=extra_wxs,
+        extra_features=extra_features,
+    )
+
+
+def run_wix_packaging(
+    source_dir: pathlib.Path,
+    build_dir: pathlib.Path,
+    staging_dir: pathlib.Path,
+    arch: str,
+    version: str,
+    orig_version: str,
+    msi_name: typing.Optional[str] = "mercurial",
+    extra_wxs: typing.Optional[typing.Dict[str, str]] = None,
+    extra_features: typing.Optional[typing.List[str]] = None,
+):
+    """Invokes WiX to package up a built Mercurial."""
+
+    wix_dir = source_dir / 'contrib' / 'packaging' / 'wix'
+
+    wix_pkg, wix_entry = download_entry('wix', build_dir)
+    wix_path = build_dir / ('wix-%s' % wix_entry['version'])
 
     if not wix_path.exists():
         extract_zip_to_directory(wix_pkg, wix_path)
 
-    ensure_vc90_merge_modules(hg_build_dir)
+    ensure_vc90_merge_modules(build_dir)
 
     source_build_rel = pathlib.Path(os.path.relpath(source_dir, build_dir))
 
     defines = {'Platform': arch}
 
     # Derive a .wxs file with the staged files.
     manifest_wxs = build_dir / 'stage.wxs'
     with manifest_wxs.open('w', encoding='utf-8') as fh:
         fh.write(make_files_xml(staging_dir, is_x64=arch == 'x64'))
 
     run_candle(wix_path, build_dir, manifest_wxs, staging_dir, defines=defines)
 
     for source, rel_path in sorted((extra_wxs or {}).items()):
         run_candle(wix_path, build_dir, source, rel_path, defines=defines)
 
     source = wix_dir / 'mercurial.wxs'
     defines['Version'] = version
     defines['Comments'] = 'Installs Mercurial version %s' % version
-    defines['VCRedistSrcDir'] = str(hg_build_dir)
+    defines['VCRedistSrcDir'] = str(build_dir)
     if extra_features:
         assert all(';' not in f for f in extra_features)
         defines['MercurialExtraFeatures'] = ';'.join(extra_features)
 
     run_candle(wix_path, build_dir, source, source_build_rel, defines=defines)
 
     msi_path = (
         source_dir / 'dist' / ('%s-%s-%s.msi' % (msi_name, orig_version, arch))
     )
 
     args = [
         str(wix_path / 'light.exe'),
         '-nologo',
         '-ext',
         'WixUIExtension',
         '-sw1076',
         '-spdb',
         '-o',
         str(msi_path),
     ]
 
     for source, rel_path in sorted((extra_wxs or {}).items()):
         assert source.endswith('.wxs')
         source = os.path.basename(source)
         args.append(str(build_dir / ('%s.wixobj' % source[:-4])))
 
     args.extend(
         [str(build_dir / 'stage.wixobj'), str(build_dir / 'mercurial.wixobj'),]
     )
 
     subprocess.run(args, cwd=str(source_dir), check=True)
 
     print('%s created' % msi_path)
 
     return {
         'msi_path': msi_path,
     }
 
 
 def build_signed_installer(
     source_dir: pathlib.Path,
     python_exe: pathlib.Path,
     name: str,
     version=None,
     subject_name=None,
     cert_path=None,
     cert_password=None,
     timestamp_url=None,
     extra_packages_script=None,
     extra_wxs=None,
     extra_features=None,
 ):
     """Build an installer with signed executables."""
 
     post_build_fn = make_post_build_signing_fn(
         name,
         subject_name=subject_name,
         cert_path=cert_path,
         cert_password=cert_password,
         timestamp_url=timestamp_url,
     )
 
     info = build_installer(
         source_dir,
         python_exe=python_exe,
         msi_name=name.lower(),
         version=version,
         post_build_fn=post_build_fn,
         extra_packages_script=extra_packages_script,
         extra_wxs=extra_wxs,
         extra_features=extra_features,
     )
 
     description = '%s %s' % (name, version)
 
     sign_with_signtool(
         info['msi_path'],
         description,
         subject_name=subject_name,
         cert_path=cert_path,
         cert_password=cert_password,
         timestamp_url=timestamp_url,
     )