### Check existing issues - [x] I've verified that this bug isn't described by any existing issues. ### Bug description When building a snap with a Python-based plugin on core26, the following error is raised: ``` Don't know which interpreter to use for base core26. Recommended resolution: Please contact the Snapcraft team. ``` This appears to be due to this function: https://github.com/canonical/snapcraft/blob/8bd9cc5222a10e07b11727313b2e1080770ed854/snapcraft/parts/plugins/python_common.py#L42 An assumption is made that all cores will contain a usable Python interpreter, and furthermore, the snap _must_ use this provided Python interpreter even if they prefer to stage their own. This behavior can't work on core26, as there isn't a Python interpreter to use. ### Steps to reproduce Attempt to build the attached project file. ### Environment Snapcraft 8.14 ### snapcraft.yaml <details> <summary>snapcraft.yaml</summary> ```yaml name: microceph base: core26 build-base: devel adopt-info: ceph grade: devel source-code: https://github.com/canonical/microceph.git license: AGPL-3.0 summary: Simple clustered Ceph deployment description: |- MicroCeph is snap-deployed Ceph with built-in clustering. confinement: strict package-repositories: - type: apt ppa: lmlogiudice/ceph-tentacle-resolute plugs: load-rbd: interface: kernel-module-load modules: - name: rbd load: on-boot slots: ceph-logs: interface: content content: logs source: read: - "$SNAP_COMMON/logs" ceph-conf: interface: content content: ceph-conf source: read: - "$SNAP_DATA/conf" environment: LD_LIBRARY_PATH: $SNAP/lib:$SNAP/lib/$CRAFT_ARCH_TRIPLET_BUILD_FOR:$SNAP/lib/$CRAFT_ARCH_TRIPLET_BUILD_FOR/ceph:$SNAP/lib:$SNAP/lib/$CRAFT_ARCH_TRIPLET_BUILD_FOR:$SNAP/lib/$CRAFT_ARCH_TRIPLET_BUILD_FOR/ceph:$SNAP/lib/ganesha:$SNAP/lib/$CRAFT_ARCH_TRIPLET_BUILD_FOR/ceph/compressor:$SNAP/lib/$CRAFT_ARCH_TRIPLET_BUILD_FOR/ceph/crypto:$SNAP/lib/$CRAFT_ARCH_TRIPLET_BUILD_FOR/ceph/erasure-code PYTHONPATH: $SNAP/lib/python3/dist-packages:$SNAP/lib/python3.13/site-packages layout: /usr/lib/$CRAFT_ARCH_TRIPLET_BUILD_FOR/ceph: symlink: $SNAP/lib/$CRAFT_ARCH_TRIPLET_BUILD_FOR/ceph /usr/lib/ganesha: symlink: $SNAP/lib/ganesha /usr/lib/$CRAFT_ARCH_TRIPLET_BUILD_FOR/rados-classes: symlink: $SNAP/lib/$CRAFT_ARCH_TRIPLET_BUILD_FOR/rados-classes /etc/ceph: bind: $SNAP_DATA/conf /etc/ganesha: bind: $SNAP_DATA/conf/ganesha /usr/share/ceph: bind: $SNAP/share/ceph /var/lib/ceph: bind: $SNAP_COMMON/data /var/log/ceph: bind: $SNAP_COMMON/logs /var/log/ganesha: bind: $SNAP_COMMON/logs/ganesha apps: # Service daemon: command: commands/daemon.start daemon: simple plugs: - block-devices - dm-crypt - hardware-observe - mount-observe - network - network-bind - microceph-support slots: - microceph mds: command: commands/mds.start daemon: simple install-mode: disable after: - daemon plugs: - network - network-bind - process-control mon: command: commands/mon.start daemon: simple install-mode: disable after: - daemon plugs: - hardware-observe - network - network-bind - process-control mgr: command: commands/mgr.start daemon: simple install-mode: disable after: - daemon plugs: - network - network-bind - process-control nfs: command: commands/nfs-ganesha.start daemon: simple install-mode: disable after: - daemon plugs: - network - network-bind - process-control osd: command: commands/osd.start reload-command: commands/osd.reload daemon: simple install-mode: disable stop-mode: sigterm-all stop-timeout: 5m after: - daemon plugs: - block-devices - dm-crypt - hardware-observe - network - network-bind - microceph-support - process-control rgw: command: commands/rgw.start daemon: simple install-mode: disable after: - daemon plugs: - hardware-observe - network - network-bind - process-control "rbd-mirror": command: commands/rbd-mirror.start daemon: simple install-mode: disable after: - daemon plugs: - network - network-bind - process-control "cephfs-mirror": command: commands/cephfs-mirror.start daemon: simple install-mode: disable after: - daemon plugs: - network - network-bind - process-control # Commands ceph: command: commands/ceph plugs: - network - home "radosgw-admin": command: commands/radosgw-admin plugs: - network microceph: command: commands/microceph plugs: - mount-observe - network - block-devices - dm-crypt - home rbd: command: commands/rbd plugs: - network - network-bind - microceph-support - dm-crypt rados: command: commands/rados plugs: - network ceph-bluestore-tool: command: commands/ceph-bluestore-tool plugs: - mount-observe - block-devices - hardware-observe ceph-authtool: command: commands/ceph-authtool plugs: - home parts: microceph-orch: plugin: python # build-snaps: # - astral-uv source: ./microceph-orch after: - microceph - ceph override-prime: | set -eux a=$(pwd) craftctl default mkdir -p share/ceph/mgr/microceph # Force copy to overwrite. cp -rf lib/python3.14/site-packages/microceph share/ceph/mgr/ ceph: plugin: nil source: patches/ override-prime: | craftctl default pkg_version=$( dpkg-deb -f \ $CRAFT_PART_SRC/../stage_packages/ceph-common*.deb Version) git_version=$( git -C $CRAFT_PROJECT_DIR describe \ --always \ --dirty \ --abbrev=10 | sed -s 's/^v//') printf "ceph-version: ${pkg_version}\nmicroceph-git: ${git_version}\n" > share/metadata.yaml override-stage: | set -eux craftctl default pkg_version=$( dpkg-deb -f \ $CRAFT_PART_SRC/../stage_packages/ceph-common*.deb \ Version | sed -rne 's/([0-9.]+)[-+].*$$/\1/p' | cut -c1-10) git_version=$( git -C $CRAFT_PROJECT_DIR describe \ --always \ --dirty \ --abbrev=10) # changed as the original string was longer than 32chars. craftctl set version=${pkg_version}+snap${git_version} # Apply patches to the staging environment to ensure # the microceph orchestrator is enabled. pushd $CRAFT_STAGE ls -l $CRAFT_PART_SRC/*.patch for quirk in `ls -1 $CRAFT_PART_SRC/*.patch` do echo "Applying patch $quirk from directory $(pwd)" patch -p1 < $quirk echo "Done applying patch $quirk" done popd stage-packages: - ceph-common - ceph-mds - ceph-mgr - ceph-mgr-dashboard - ceph-mon - ceph-osd - radosgw - rbd-mirror - cephfs-mirror # Utilities - coreutils - util-linux - uuid-runtime - python3-setuptools - python3-packaging - libatomic1 - python3-ceph-common # used by microceph-orch organize: usr/bin/: bin/ usr/sbin/: bin/ usr/lib/: lib/ usr/share/: share/ prime: - bin/ceph - bin/ceph-authtool - bin/ceph-bluestore-tool - bin/ceph-mds - bin/ceph-mgr - bin/ceph-mon - bin/ceph-osd - bin/ceph-conf - bin/monmaptool - bin/rbd - bin/rados - bin/radosgw - bin/radosgw-admin - bin/rbd-mirror - bin/cephfs-mirror - bin/truncate - bin/uuidgen - bin/findmnt - lib/*/ceph - lib/*/libaio.so* - lib/*/libasn1.so* - lib/*/libatomic.so* - lib/*/libboost_context.so* - lib/*/libboost_filesystem.so* - lib/*/libboost_iostreams.so* - lib/*/libboost_locale.so* - lib/*/libboost_program_options.so* - lib/*/libboost_python313.so* - lib/*/libboost_thread.so* - lib/*/libboost_url.so* - lib/*/libcephfs.so* - lib/*/libcephsqlite.so* - lib/*/libcurl-gnutls.so* - lib/*/libdaxctl.so* - lib/*/libfuse3.so* - lib/*/libibverbs.so* - lib/*/libicudata.so* - lib/*/libicui18n.so* - lib/*/libicuuc.so* - lib/*/liblber.so* - lib/*/libldap.so* - lib/*/liblua5.4.so* - lib/*/libnbd.so* - lib/*/libncurses.so* - lib/*/libndctl.so* - lib/*/libnghttp2.so* - lib/*/libnuma.so* - lib/*/liboath.so* - lib/*/libpmem.so* - lib/*/libpmemobj.so* - lib/*/libpsl.so* - lib/*/libpython3.13.so* - lib/*/librabbitmq.so* - lib/*/librados.so* - lib/*/libradosgw.so* - lib/*/libradosstriper.so.* - lib/*/librbd.so* - lib/*/librdmacm.so* - lib/*/libroken.so* - lib/*/librtmp.so* - lib/*/libsasl2.so* - lib/*/libsnappy.so* - lib/*/libssh.so* - lib/*/libwind.so* - lib/*/libxml2.so* - lib/python3 - lib/*/rados-classes - lib/*/libtcmalloc.so* - lib/*/libunwind.so* - lib/*/liblmdb.so* - share/ceph dqlite: source: https://github.com/canonical/dqlite source-type: git source-depth: 1 source-tag: v1.18.5 plugin: autotools autotools-configure-parameters: - --prefix= - --enable-build-raft stage-packages: - libuv1 - libsqlite3-0 - liblz4-1 build-packages: - make - libuv1-dev - liblz4-dev - libsqlite3-dev - pkg-config organize: usr/lib/: lib/ prime: - lib/libdqlite*so* - lib/libraft*so* - lib/*/libuv*so* microceph: source: microceph/ after: - dqlite build-snaps: - go plugin: nil override-pull: | craftctl default set -ex # Download the dependencies go get -d -v ./... override-build: | set -ex git_diff="$( git -C $CRAFT_PROJECT_DIR status -uno --porcelain )" if [ -n "$git_diff" ]; then echo "==================================================" echo "STOP the build: dirty worktree detected" echo "$git_diff" echo "==================================================" exit 1 fi # Setup build environment export CGO_CFLAGS="-I${CRAFT_STAGE}/include/ -I${CRAFT_STAGE}/usr/local/include/" export CGO_LDFLAGS="-L${CRAFT_STAGE}/lib/ -L${CRAFT_STAGE}/usr/local/lib/" export CGO_LDFLAGS_ALLOW="(-Wl,-wrap,pthread_create)|(-Wl,-z,now)" pkg_version=$( apt-cache policy ceph-common | awk '/Candidate:/{ print $2 }' ) git_version=$( git -C $CRAFT_PROJECT_DIR describe \ --always \ --dirty \ --abbrev=10) export MC_VERSION="ceph-version: $pkg_version; microceph-git: $git_version" # Build the binaries go build -trimpath -o "${CRAFT_PART_INSTALL}/bin/microceph" -ldflags "-X 'github.com/canonical/microceph/microceph/version.version=${MC_VERSION}'" ./cmd/microceph go build -trimpath -o "${CRAFT_PART_INSTALL}/bin/microcephd" -tags=libsqlite3 -ldflags "-X 'github.com/canonical/microceph/microceph/version.version=${MC_VERSION}'" ./cmd/microcephd # Strip binaries strip -s "${CRAFT_PART_INSTALL}/bin/microceph" strip -s "${CRAFT_PART_INSTALL}/bin/microcephd" prime: - bin/microceph - bin/microcephd nfs-ganesha: plugin: nil stage-packages: - nfs-ganesha - nfs-ganesha-ceph - nfs-ganesha-rados-grace organize: sbin/: bin/ usr/bin/: bin/ usr/sbin/: bin/ usr/lib/: lib/ prime: - bin/* - lib/*/ganesha - lib/*/libevent_core-*.so* - lib/*/libganesha_*.so* - lib/*/libnfsidmap.so* - lib/*/libntirpc.so* - lib/*/liburcu-bp.so* - lib/*/libwbclient.so* strip: after: - ceph - dqlite - microceph plugin: nil override-prime: | set -x # Strip libraries (excluding python3 scripts) find "${CRAFT_PRIME}"/lib -type f \ -not -path "${CRAFT_PRIME}/lib/python3*/*" \ -exec strip -s {} + wrappers: plugin: dump source: snapcraft/ ``` </details> ### Log output ```shell Don't know which interpreter to use for base core26. Recommended resolution: Please contact the Snapcraft team. ```