dev-python/dnspython: Make DNSSEC support optional (cryptography dep)

Thanks to Michael Orlitzky.

Closes: https://bugs.gentoo.org/844058
Signed-off-by: Michał Górny <mgorny@gentoo.org>

dev-python/dnspython/dnspython-2.2.1-r1.ebuild

@@ -0,0 +1,52 @@
+# Copyright 1999-2022 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=8
+
+DISTUTILS_USE_PEP517=poetry
+PYTHON_COMPAT=( python3_{8..11} pypy3 )
+
+inherit distutils-r1
+
+DESCRIPTION="DNS toolkit for Python"
+HOMEPAGE="
+	https://www.dnspython.org/
+	https://github.com/rthalley/dnspython/
+	https://pypi.org/project/dnspython/
+"
+SRC_URI="
+	https://github.com/rthalley/dnspython/archive/v${PV}.tar.gz
+		-> ${P}.tar.gz
+"
+
+LICENSE="ISC"
+SLOT="0"
+KEYWORDS="~alpha ~amd64 ~arm ~arm64 ~hppa ~ia64 ~loong ~mips ~ppc ~ppc64 ~riscv ~s390 ~sparc ~x86 ~amd64-linux ~x86-linux ~ppc-macos ~x64-macos ~x86-solaris"
+IUSE="dnssec examples"
+
+RDEPEND="
+	dnssec? (
+		dev-python/cryptography[${PYTHON_USEDEP}]
+	)
+	<dev-python/idna-4.0[${PYTHON_USEDEP}]
+"
+
+distutils_enable_tests pytest
+
+src_prepare() {
+	sed -i -e '/network_avail/s:True:False:' \
+		tests/*.py || die
+	distutils-r1_src_prepare
+}
+
+python_test() {
+	epytest -s
+}
+
+python_install_all() {
+	distutils-r1_python_install_all
+	if use examples; then
+		dodoc -r examples
+		docompress -x /usr/share/doc/${PF}/examples
+	fi
+}

dev-python/dnspython/metadata.xml

@@ -21,6 +21,12 @@ DNSPythonはPython言語用のDNSツールキットです。ほとんどのレ
 い、その戻り値を使います。低水準はゾーン、メッセージ、ネーム、レコードを直接操作
 します。
 	</longdescription>
+	<use>
+		<flag name="dnssec">
+			Use <pkg>dev-python/cryptography</pkg> to enable low-level
+			DNSSEC RSA, DSA, ECDSA and EdDSA signature validation.
+		</flag>
+	</use>
 	<stabilize-allarches/>
 	<upstream>
 		<remote-id type="pypi">dnspython</remote-id>