Python pybind

.github/workflows/build.yaml

@@ -53,6 +53,7 @@ jobs:
               -DWITH_LUA=OFF
               -DWITH_OPENMP=OFF
               -DWITH_PLUGINS=OFF
+              -DWITH_PYBIND=OFF
               -DWITH_SRC=OFF
               -DWITH_TESTS=OFF
               -DWITH_TOOLS=OFF
@@ -90,6 +91,11 @@ jobs:
       - name: Build
         run: cmake --build build ${{ env.CMAKE_BUILD_OPTS }}
 
+      # WITH_PYBIND is silently disabled when pybind11 is missing
+      - name: Verify the Python bindings were built
+        if: matrix.distro == 'fedora'
+        run: test -f build/python/binding/_core*.so
+
       - name: Upload Build Artifacts
         uses: actions/upload-artifact@v7
         with:

.github/workflows/ci.yaml

@@ -110,6 +110,15 @@ jobs:
       ref: ${{ needs.setup.outputs.ref }}
       ref_name: ${{ needs.setup.outputs.ref_name }}
 
+  packaging-python:
+    name: Build Python Wheels
+    needs: [setup]
+    secrets: inherit
+    uses: ./.github/workflows/packaging-python.yaml
+    with:
+      container_image: ${{ needs.setup.outputs.container_image }}
+      ref: ${{ needs.setup.outputs.ref }}
+
   packaging-nix:
     name: Bundle Artifacts with Nix
     needs: [setup, nix]
@@ -162,6 +171,7 @@ jobs:
       - test
       - packaging-container
       - packaging-nix
+      - packaging-python
       - deploy
       - deploy-nix
     runs-on: ubuntu-latest

.github/workflows/packaging-python.yaml

@@ -0,0 +1,144 @@
+# SPDX-FileCopyrightText: 2026 Institute for Automation of Complex Power Systems, RWTH Aachen University
+# SPDX-License-Identifier: Apache-2.0
+
+name: Packaging (Python)
+
+on:
+  workflow_call:
+    inputs:
+      container_image:
+        required: true
+        type: string
+      ref:
+        description: 'Revision under test'
+        required: true
+        type: string
+  workflow_dispatch:
+
+permissions:
+  contents: read
+  packages: write
+
+jobs:
+  sdist:
+    name: Source distribution
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v7
+        with:
+          ref: ${{ inputs.ref || github.sha }}
+          allow-unsafe-pr-checkout: true
+          submodules: recursive
+
+      - name: Set up Python
+        uses: actions/setup-python@v6
+        with:
+          python-version: '3.13'
+
+      - name: Build source distribution
+        run: pipx run build --sdist --outdir dist/
+
+      - name: Archive source distribution
+        uses: actions/upload-artifact@v7
+        with:
+          name: python-sdist
+          path: dist/
+
+  image:
+    name: Prepare Wheel Build Image
+    runs-on: ubuntu-latest
+    outputs:
+      image: ${{ steps.image.outputs.image }}
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v7
+        with:
+          ref: ${{ inputs.ref || github.sha }}
+          allow-unsafe-pr-checkout: true
+          submodules: recursive
+
+      - name: Login to Registry
+        uses: docker/login-action@v4
+        with:
+          registry: ghcr.io
+          username: ${{ github.actor }}
+          password: ${{ github.token }}
+
+      - name: Set up Buildx
+        uses: docker/setup-buildx-action@v4
+
+      # Tagged by recipe, so the image is built once and pulled afterwards
+      - name: Compute image name
+        id: image
+        env:
+          CONTAINER_IMAGE: ${{ inputs.container_image }}
+          REPOSITORY: ${{ github.repository }}
+        run: |
+          HASH=$(cat packaging/docker/Dockerfile.manylinux packaging/deps.sh \
+            $(find packaging/patches -type f | sort) | sha256sum | cut -c1-16)
+          echo "image=${CONTAINER_IMAGE:-ghcr.io/${REPOSITORY,,}}/manylinux:${HASH}" >> "$GITHUB_OUTPUT"
+          echo "latest=${CONTAINER_IMAGE:-ghcr.io/${REPOSITORY,,}}/manylinux:latest" >> "$GITHUB_OUTPUT"
+
+      - name: Check for an existing image
+        id: existing
+        env:
+          IMAGE: ${{ steps.image.outputs.image }}
+        run: |
+          if docker buildx imagetools inspect "${IMAGE}" >/dev/null 2>&1; then
+            echo "found=true" >> "$GITHUB_OUTPUT"
+          else
+            echo "found=false" >> "$GITHUB_OUTPUT"
+          fi
+
+      - name: Build and Push Image
+        if: steps.existing.outputs.found == 'false'
+        uses: docker/build-push-action@v7
+        with:
+          context: .
+          file: packaging/docker/Dockerfile.manylinux
+          push: true
+          cache-from: type=gha,scope=manylinux
+          cache-to: ${{ github.event_name != 'pull_request_target' && 'type=gha,mode=max,scope=manylinux' || '' }}
+          tags: |
+            ${{ steps.image.outputs.image }}
+            ${{ github.event_name == 'push' && steps.image.outputs.latest || '' }}
+
+  wheels:
+    name: Wheel (${{ matrix.python }}, ${{ matrix.variant }})
+    needs: [image]
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        python: [cp310, cp311, cp312, cp313, cp314]
+        variant: [apache, gpl]
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v7
+        with:
+          ref: ${{ inputs.ref || github.sha }}
+          allow-unsafe-pr-checkout: true
+          submodules: recursive
+
+      - name: Login to Registry
+        uses: docker/login-action@v4
+        with:
+          registry: ghcr.io
+          username: ${{ github.actor }}
+          password: ${{ github.token }}
+
+      - name: Build wheel
+        uses: pypa/cibuildwheel@v4.2.0
+        env:
+          CIBW_BUILD: ${{ matrix.python }}-manylinux_x86_64
+          CIBW_MANYLINUX_X86_64_IMAGE: ${{ needs.image.outputs.image }}
+          CIBW_ENVIRONMENT_PASS_LINUX: SKBUILD_CMAKE_DEFINE VILLAS_WHEEL_VARIANT
+          SKBUILD_CMAKE_DEFINE: ${{ matrix.variant == 'gpl' && 'WITHOUT_GPL=OFF' || '' }}
+          VILLAS_WHEEL_VARIANT: ${{ matrix.variant }}
+
+      - name: Archive wheel
+        uses: actions/upload-artifact@v7
+        with:
+          name: python-wheel-${{ matrix.variant }}-${{ matrix.python }}
+          path: wheelhouse/

CMakeLists.txt

@@ -94,6 +94,8 @@ find_package(Criterion)
 find_package(OpalOrchestra)
 find_package(LibXml2)
 find_package(OpalAsyncApi)
+find_package(Python3 COMPONENTS Interpreter Development.Module)
+find_package(pybind11 CONFIG QUIET)
 
 # Check for tools
 find_program(PROTOBUFC_COMPILER NAMES protoc-c)
@@ -190,6 +192,7 @@ cmake_dependent_option(WITH_HOOKS               "Build with support for processi
 cmake_dependent_option(WITH_LUA                 "Build with Lua"                                        "${WITH_DEFAULTS}" "LUA_FOUND" OFF)
 cmake_dependent_option(WITH_OPENMP              "Build with support for OpenMP for parallel hooks"      "${WITH_DEFAULTS}" "OPENMP_FOUND" OFF)
 cmake_dependent_option(WITH_PLUGINS             "Build plugins"                                         "${WITH_DEFAULTS}" "TOPLEVEL_PROJECT" OFF)
+cmake_dependent_option(WITH_PYBIND              "Build Python bindings"                                 "${WITH_DEFAULTS}" "pybind11_FOUND; Python3_FOUND" OFF)
 cmake_dependent_option(WITH_SRC                 "Build executables"                                     "${WITH_DEFAULTS}" "TOPLEVEL_PROJECT" OFF)
 cmake_dependent_option(WITH_TESTS               "Run tests"                                             "${WITH_DEFAULTS}" "TOPLEVEL_PROJECT" OFF)
 cmake_dependent_option(WITH_TOOLS               "Build auxilary tools"                                  "${WITH_DEFAULTS}" "TOPLEVEL_PROJECT" OFF)
@@ -301,6 +304,7 @@ add_feature_info(HOOKS                  WITH_HOOKS                  "Build with
 add_feature_info(LUA                    WITH_LUA                    "Build with Lua support")
 add_feature_info(OPENMP                 WITH_OPENMP                 "Build with OpenMP support")
 add_feature_info(PLUGINS                WITH_PLUGINS                "Build plugins")
+add_feature_info(PYBIND                 WITH_PYBIND                 "Build Python bindings")
 add_feature_info(SRC                    WITH_SRC                    "Build executables")
 add_feature_info(TESTS                  WITH_TESTS                  "Run tests")
 add_feature_info(TOOLS                  WITH_TOOLS                  "Build auxilary tools")

flake.nix

@@ -66,7 +66,10 @@
       packagesWith = pkgs: rec {
         default = villas-node;
 
-        villas-node-python = pkgs.callPackage (nixDir + "/python.nix") { src = ./.; };
+        villas-node-python = pkgs.callPackage (nixDir + "/python.nix") {
+          src = ./.;
+          villas = villas-node-minimal;
+        };
 
         villas-node-minimal = pkgs.callPackage (nixDir + "/villas.nix") {
           src = ./.;

lib/hook_list.cpp

@@ -189,6 +189,9 @@ void HookList::dump(Logger logger, std::string subject) const {
   logger->debug("Hooks of {}:", subject);
 
   unsigned i = 0;
-  for (auto h : *this)
-    logger->debug("      {}: {}", i++, h->getFactory()->getName());
+  for (auto h : *this) {
+    auto *f = h->getFactory();
+
+    logger->debug("      {}: {}", i++, f ? f->getName() : "unnamed");
+  }
 }

lib/node.cpp

@@ -440,7 +440,7 @@ Node *NodeFactory::make(json_t *json, const uuid_t &id,
   std::string type;
   Node *n;
 
-  if (json_is_object(json))
+  if (!json_is_object(json))
     throw ConfigError(json, "node-config-node",
                       "Node configuration must be an object");
 

lib/node_capi.cpp

@@ -59,7 +59,7 @@ int node_restart(vnode *n) {
 
 int node_destroy(vnode *n) {
   auto *nc = (Node *)n;
-  nc->~Node();
+  delete nc;
   return 0;
 }
 

packaging/check-wheel.py

@@ -0,0 +1,75 @@
+"""
+SPDX-FileCopyrightText: 2026 Institute for Automation of Complex Power Systems, RWTH Aachen University
+SPDX-License-Identifier: Apache-2.0
+"""  # noqa: E501
+
+import json
+import os
+
+import villas.node as vn
+
+# Node-types disappear silently when a dependency is missing at configure time
+REQUIRED = {
+    "amqp",
+    "c37.118",
+    "can",
+    "comedi",
+    "exec",
+    "file",
+    "infiniband",
+    "influxdb",
+    "kafka",
+    "loopback",
+    "modbus",
+    "mqtt",
+    "nanomsg",
+    "ngsi",
+    "redis",
+    "rtp",
+    "shmem",
+    "signal.v2",
+    "socket",
+    "stats",
+    "temper",
+    "test_rtt",
+    "uldaq",
+    "webrtc",
+    "websocket",
+}
+
+GPL = {
+    "ethercat",
+    "iec60870-5-104",
+    "iec61850-8-1",
+    "iec61850-9-2",
+    "zeromq",
+}
+
+gpl = os.environ.get("VILLAS_WHEEL_VARIANT") == "gpl"
+
+types = set(vn.node_types())
+
+missing = sorted((REQUIRED | GPL if gpl else REQUIRED) - types)
+if missing:
+    raise SystemExit(f"node-types missing from the wheel: {missing}")
+
+if not gpl and GPL & types:
+    raise SystemExit(f"GPL node-types in an Apache-2.0 wheel: {sorted(GPL & types)}")
+
+config = {
+    "type": "signal.v2",
+    "limit": 1,
+    "rate": 100.0,
+    "in": {"signals": [{"name": "sine", "signal": "sine"}]},
+}
+
+node = vn.Node(json.dumps(config), "check")
+node.check()
+node.prepare()
+node.start()
+sample = node.read()[0]
+node.stop()
+
+print(
+    f"{len(types)} node-types, {len(vn.hook_types())} hooks, read {sample.length} value"
+)

packaging/docker/Dockerfile.fedora

@@ -28,7 +28,7 @@ RUN dnf -y install \
 	openssh-clients \
 	jq nmap-ncat \
 	iproute iproute-tc \
-	python python-devel python-pip \
+	python python-devel python-pip pybind11-devel \
 	gdb gdb-gdbserver \
 	cppcheck \
 	xmlto dblatex rubygem-asciidoctor \
@@ -85,8 +85,9 @@ RUN bash /deps/deps.sh
 RUN ln -s /usr/lib64/tc /usr/lib/tc
 
 # Install Python dev tools for CI
-COPY ./python /python
-RUN pip install /python[dev] && \
+COPY ./pyproject.toml ./LICENSE /python/
+COPY ./python /python/python
+RUN pip install --config-settings=wheel.cmake=false "/python[dev]" && \
 	rm -r /python
 
 # Expose ports for HTTP and WebSocket frontend