Errors when installing onnx with pip in Ubuntu 20.04 - python-3.x

Question

I'm trying to install onnx in a fresh Ubuntu 20.04 install, but I'm running into the error bellow. It seems that I need the protobuf compiler, although I haven't found any documentation that says that I need that package installed.
$ sudo python3 -m pip install 'onnx>=1.1.2'
Collecting onnx>=1.1.2
Using cached onnx-1.6.0.tar.gz (3.1 MB)
Requirement already satisfied: numpy in /usr/local/lib/python3.8/dist-packages (from onnx>=1.1.2) (1.18.3)
Requirement already satisfied: protobuf in /usr/lib/python3/dist-packages (from onnx>=1.1.2) (3.6.1)
Requirement already satisfied: six in /usr/lib/python3/dist-packages (from onnx>=1.1.2) (1.14.0)
Requirement already satisfied: typing-extensions>=3.6.2.1 in /usr/local/lib/python3.8/dist-packages (from onnx>=1.1.2) (3.7.4.2)
Building wheels for collected packages: onnx
Building wheel for onnx (setup.py) ... error
ERROR: Command errored out with exit status 1:
command: /usr/bin/python3 -u -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'/tmp/pip-install-akurq0e8/onnx/setup.py'"'"'; __file__='"'"'/tmp/pip-install-akurq0e8/onnx/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' bdist_wheel -d /tmp/pip-wheel-zmzgb0kg
cwd: /tmp/pip-install-akurq0e8/onnx/
Complete output (64 lines):
fatal: not a git repository (or any of the parent directories): .git
running bdist_wheel
running build
running build_py
running create_version
running cmake_build
-- The C compiler identification is GNU 9.3.0
-- The CXX compiler identification is GNU 9.3.0
-- Check for working C compiler: /usr/bin/cc
-- Check for working C compiler: /usr/bin/cc -- works
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Detecting C compile features
-- Detecting C compile features - done
-- Check for working CXX compiler: /usr/bin/c++
-- Check for working CXX compiler: /usr/bin/c++ -- works
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Detecting CXX compile features
-- Detecting CXX compile features - done
Generated: /tmp/pip-install-akurq0e8/onnx/.setuptools-cmake-build/onnx/onnx-ml.proto
CMake Error at CMakeLists.txt:248 (message):
Protobuf compiler not found
Call Stack (most recent call first):
CMakeLists.txt:279 (relative_protobuf_generate_cpp)
-- Configuring incomplete, errors occurred!
See also "/tmp/pip-install-akurq0e8/onnx/.setuptools-cmake-build/CMakeFiles/CMakeOutput.log".
Traceback (most recent call last):
File "<string>", line 1, in <module>
File "/tmp/pip-install-akurq0e8/onnx/setup.py", line 315, in <module>
setuptools.setup(
File "/usr/lib/python3/dist-packages/setuptools/__init__.py", line 144, in setup
return distutils.core.setup(**attrs)
File "/usr/lib/python3.8/distutils/core.py", line 148, in setup
dist.run_commands()
File "/usr/lib/python3.8/distutils/dist.py", line 966, in run_commands
self.run_command(cmd)
File "/usr/lib/python3.8/distutils/dist.py", line 985, in run_command
cmd_obj.run()
File "/usr/lib/python3/dist-packages/wheel/bdist_wheel.py", line 223, in run
self.run_command('build')
File "/usr/lib/python3.8/distutils/cmd.py", line 313, in run_command
self.distribution.run_command(command)
File "/usr/lib/python3.8/distutils/dist.py", line 985, in run_command
cmd_obj.run()
File "/usr/lib/python3.8/distutils/command/build.py", line 135, in run
self.run_command(cmd_name)
File "/usr/lib/python3.8/distutils/cmd.py", line 313, in run_command
self.distribution.run_command(command)
File "/usr/lib/python3.8/distutils/dist.py", line 985, in run_command
cmd_obj.run()
File "/tmp/pip-install-akurq0e8/onnx/setup.py", line 209, in run
self.run_command('cmake_build')
File "/usr/lib/python3.8/distutils/cmd.py", line 313, in run_command
self.distribution.run_command(command)
File "/usr/lib/python3.8/distutils/dist.py", line 985, in run_command
cmd_obj.run()
File "/tmp/pip-install-akurq0e8/onnx/setup.py", line 195, in run
subprocess.check_call(cmake_args)
File "/usr/lib/python3.8/subprocess.py", line 364, in check_call
raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command '['/usr/bin/cmake', '-DPYTHON_INCLUDE_DIR=/usr/include/python3.8', '-DPYTHON_EXECUTABLE=/usr/bin/python3', '-DBUILD_ONNX_PYTHON=ON', '-DCMAKE_EXPORT_COMPILE_COMMANDS=ON', '-DONNX_NAMESPACE=onnx', '-DPY_EXT_SUFFIX=.cpython-38-x86_64-linux-gnu.so', '-DCMAKE_BUILD_TYPE=Release', '-DONNX_ML=1', '/tmp/pip-install-akurq0e8/onnx']' returned non-zero exit status 1.
----------------------------------------
ERROR: Failed building wheel for onnx
Running setup.py clean for onnx
Failed to build onnx
Installing collected packages: onnx
Running setup.py install for onnx ... error
ERROR: Command errored out with exit status 1:
command: /usr/bin/python3 -u -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'/tmp/pip-install-akurq0e8/onnx/setup.py'"'"'; __file__='"'"'/tmp/pip-install-akurq0e8/onnx/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' install --record /tmp/pip-record-txzgh5wg/install-record.txt --single-version-externally-managed --compile --install-headers /usr/local/include/python3.8/onnx
cwd: /tmp/pip-install-akurq0e8/onnx/
Complete output (52 lines):
fatal: not a git repository (or any of the parent directories): .git
running install
running build
running build_py
running create_version
running cmake_build
Generated: /tmp/pip-install-akurq0e8/onnx/.setuptools-cmake-build/onnx/onnx-ml.proto
CMake Error at CMakeLists.txt:248 (message):
Protobuf compiler not found
Call Stack (most recent call first):
CMakeLists.txt:279 (relative_protobuf_generate_cpp)
-- Configuring incomplete, errors occurred!
See also "/tmp/pip-install-akurq0e8/onnx/.setuptools-cmake-build/CMakeFiles/CMakeOutput.log".
Traceback (most recent call last):
File "<string>", line 1, in <module>
File "/tmp/pip-install-akurq0e8/onnx/setup.py", line 315, in <module>
setuptools.setup(
File "/usr/lib/python3/dist-packages/setuptools/__init__.py", line 144, in setup
return distutils.core.setup(**attrs)
File "/usr/lib/python3.8/distutils/core.py", line 148, in setup
dist.run_commands()
File "/usr/lib/python3.8/distutils/dist.py", line 966, in run_commands
self.run_command(cmd)
File "/usr/lib/python3.8/distutils/dist.py", line 985, in run_command
cmd_obj.run()
File "/usr/lib/python3/dist-packages/setuptools/command/install.py", line 61, in run
return orig.install.run(self)
File "/usr/lib/python3.8/distutils/command/install.py", line 589, in run
self.run_command('build')
File "/usr/lib/python3.8/distutils/cmd.py", line 313, in run_command
self.distribution.run_command(command)
File "/usr/lib/python3.8/distutils/dist.py", line 985, in run_command
cmd_obj.run()
File "/usr/lib/python3.8/distutils/command/build.py", line 135, in run
self.run_command(cmd_name)
File "/usr/lib/python3.8/distutils/cmd.py", line 313, in run_command
self.distribution.run_command(command)
File "/usr/lib/python3.8/distutils/dist.py", line 985, in run_command
cmd_obj.run()
File "/tmp/pip-install-akurq0e8/onnx/setup.py", line 209, in run
self.run_command('cmake_build')
File "/usr/lib/python3.8/distutils/cmd.py", line 313, in run_command
self.distribution.run_command(command)
File "/usr/lib/python3.8/distutils/dist.py", line 985, in run_command
cmd_obj.run()
File "/tmp/pip-install-akurq0e8/onnx/setup.py", line 195, in run
subprocess.check_call(cmake_args)
File "/usr/lib/python3.8/subprocess.py", line 364, in check_call
raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command '['/usr/bin/cmake', '-DPYTHON_INCLUDE_DIR=/usr/include/python3.8', '-DPYTHON_EXECUTABLE=/usr/bin/python3', '-DBUILD_ONNX_PYTHON=ON', '-DCMAKE_EXPORT_COMPILE_COMMANDS=ON', '-DONNX_NAMESPACE=onnx', '-DPY_EXT_SUFFIX=.cpython-38-x86_64-linux-gnu.so', '-DCMAKE_BUILD_TYPE=Release', '-DONNX_ML=1', '/tmp/pip-install-akurq0e8/onnx']' returned non-zero exit status 1.
----------------------------------------
ERROR: Command errored out with exit status 1: /usr/bin/python3 -u -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'/tmp/pip-install-akurq0e8/onnx/setup.py'"'"'; __file__='"'"'/tmp/pip-install-akurq0e8/onnx/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' install --record /tmp/pip-record-txzgh5wg/install-record.txt --single-version-externally-managed --compile --install-headers /usr/local/include/python3.8/onnx Check the logs for full command output.
Then I tried installing the protobuf compiler (sudo apt install protobuf-compiler) and now I get this other error, which seems to indicate that some script in the installation process requires a python binary. Since this is Ubuntu 20.04, no python 2.7 is installed and no python binary exists.
sudo pip3 install 'onnx>=1.1.2'
Collecting onnx>=1.1.2
Using cached onnx-1.6.0.tar.gz (3.1 MB)
Requirement already satisfied: numpy in /usr/local/lib/python3.8/dist-packages (from onnx>=1.1.2) (1.18.3)
Requirement already satisfied: protobuf in /usr/lib/python3/dist-packages (from onnx>=1.1.2) (3.6.1)
Requirement already satisfied: six in /usr/lib/python3/dist-packages (from onnx>=1.1.2) (1.14.0)
Requirement already satisfied: typing-extensions>=3.6.2.1 in /usr/local/lib/python3.8/dist-packages (from onnx>=1.1.2) (3.7.4.2)
Building wheels for collected packages: onnx
Building wheel for onnx (setup.py) ... error
ERROR: Command errored out with exit status 1:
command: /usr/bin/python3 -u -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'/tmp/pip-install-t7al85w7/onnx/setup.py'"'"'; __file__='"'"'/tmp/pip-install-t7al85w7/onnx/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' bdist_wheel -d /tmp/pip-wheel-30aavuu6
cwd: /tmp/pip-install-t7al85w7/onnx/
Complete output (135 lines):
fatal: not a git repository (or any of the parent directories): .git
running bdist_wheel
running build
running build_py
running create_version
running cmake_build
-- The C compiler identification is GNU 9.3.0
-- The CXX compiler identification is GNU 9.3.0
-- Check for working C compiler: /usr/bin/cc
-- Check for working C compiler: /usr/bin/cc -- works
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Detecting C compile features
-- Detecting C compile features - done
-- Check for working CXX compiler: /usr/bin/c++
-- Check for working CXX compiler: /usr/bin/c++ -- works
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- Found Protobuf: /usr/lib/x86_64-linux-gnu/libprotobuf.so;-lpthread (found version "3.6.1")
Generated: /tmp/pip-install-t7al85w7/onnx/.setuptools-cmake-build/onnx/onnx-ml.proto
Generated: /tmp/pip-install-t7al85w7/onnx/.setuptools-cmake-build/onnx/onnx-operators-ml.proto
CMake Warning at CMakeLists.txt:394 (find_package):
By not providing "Findpybind11.cmake" in CMAKE_MODULE_PATH this project has
asked CMake to find a package configuration file provided by "pybind11",
but CMake did not find one.
Could not find a package configuration file provided by "pybind11"
(requested version 2.2) with any of the following names:
pybind11Config.cmake
pybind11-config.cmake
Add the installation prefix of "pybind11" to CMAKE_PREFIX_PATH or set
"pybind11_DIR" to a directory containing one of the above files. If
"pybind11" provides a separate development package or SDK, be sure it has
been installed.
--
-- ******** Summary ********
-- CMake version : 3.16.3
-- CMake command : /usr/bin/cmake
-- System : Linux
-- C++ compiler : /usr/bin/c++
-- C++ compiler version : 9.3.0
-- CXX flags : -Wnon-virtual-dtor
-- Build type : Release
-- Compile definitions :
-- CMAKE_PREFIX_PATH :
-- CMAKE_INSTALL_PREFIX : /usr/local
-- CMAKE_MODULE_PATH :
--
-- ONNX version : 1.6.0
-- ONNX NAMESPACE : onnx
-- ONNX_BUILD_TESTS : OFF
-- ONNX_BUILD_BENCHMARKS : OFF
-- ONNX_USE_LITE_PROTO : OFF
-- ONNXIFI_DUMMY_BACKEND : OFF
-- ONNXIFI_ENABLE_EXT : OFF
--
-- Protobuf compiler : /usr/bin/protoc
-- Protobuf includes : /usr/include
-- Protobuf libraries : /usr/lib/x86_64-linux-gnu/libprotobuf.so;-lpthread
-- BUILD_ONNX_PYTHON : ON
-- Python version :
-- Python executable : /usr/bin/python3
-- Python includes : /usr/include/python3.8
-- Configuring done
-- Generating done
-- Build files have been written to: /tmp/pip-install-t7al85w7/onnx/.setuptools-cmake-build
Scanning dependencies of target gen_onnx_proto
Scanning dependencies of target onnxifi_loader
Scanning dependencies of target onnxifi_dummy
[ 1%] Building C object CMakeFiles/onnxifi_dummy.dir/onnx/onnxifi_dummy.c.o
[ 3%] Building C object CMakeFiles/onnxifi_loader.dir/onnx/onnxifi_loader.c.o
[ 4%] Running gen_proto.py on onnx/onnx.in.proto
/tmp/pip-install-t7al85w7/onnx/onnx/onnxifi_dummy.c: In function ‘onnxGetExtensionFunctionAddress’:
/tmp/pip-install-t7al85w7/onnx/onnx/onnxifi_dummy.c:173:21: warning: assignment to ‘onnxExtensionFunctionPointer’ {aka ‘int (*)(void)’} from incompatible pointer type ‘onnxStatus (*)(void *, const char *, onnxStatus (**)(void))’ {aka ‘int (*)(void *, const char *, int (**)(void))’} [-Wincompatible-pointer-types]
173 | *function = &onnxGetExtensionFunctionAddress;
| ^
/tmp/pip-install-t7al85w7/onnx/onnx/onnxifi_dummy.c:176:21: warning: assignment to ‘onnxExtensionFunctionPointer’ {aka ‘int (*)(void)’} from incompatible pointer type ‘onnxStatus (*)(void *, uint32_t, const onnxTensorDescriptorV1 *, uint32_t, const onnxTensorDescriptorV1 *, onnxMemoryFenceV1 *)’ {aka ‘int (*)(void *, unsigned int, const struct onnxTensorDescriptorV1 *, unsigned int, const struct onnxTensorDescriptorV1 *, struct onnxMemoryFenceV1 *)’} [-Wincompatible-pointer-types]
176 | *function = &onnxSetIOAndRunGraph;
| ^
Processing /tmp/pip-install-t7al85w7/onnx/onnx/onnx.in.proto
Writing /tmp/pip-install-t7al85w7/onnx/.setuptools-cmake-build/onnx/onnx-ml.proto
Writing /tmp/pip-install-t7al85w7/onnx/.setuptools-cmake-build/onnx/onnx-ml.proto3
generating /tmp/pip-install-t7al85w7/onnx/.setuptools-cmake-build/onnx/onnx_pb.py
[ 6%] Running C++ protocol buffer compiler on /tmp/pip-install-t7al85w7/onnx/.setuptools-cmake-build/onnx/onnx-ml.proto
[ 8%] Linking C static library libonnxifi_loader.a
/usr/bin/env: ‘python’: No such file or directory
--mypy_out: protoc-gen-mypy: Plugin failed with status code 127.
make[2]: *** [CMakeFiles/gen_onnx_proto.dir/build.make:62: onnx/onnx-ml.pb.cc] Error 1
make[1]: *** [CMakeFiles/Makefile2:250: CMakeFiles/gen_onnx_proto.dir/all] Error 2
make[1]: *** Waiting for unfinished jobs....
[ 9%] Linking C shared library libonnxifi_dummy.so
[ 9%] Built target onnxifi_loader
[ 9%] Built target onnxifi_dummy
make: *** [Makefile:130: all] Error 2
Traceback (most recent call last):
File "<string>", line 1, in <module>
File "/tmp/pip-install-t7al85w7/onnx/setup.py", line 315, in <module>
setuptools.setup(
File "/usr/lib/python3/dist-packages/setuptools/__init__.py", line 144, in setup
return distutils.core.setup(**attrs)
File "/usr/lib/python3.8/distutils/core.py", line 148, in setup
dist.run_commands()
File "/usr/lib/python3.8/distutils/dist.py", line 966, in run_commands
self.run_command(cmd)
File "/usr/lib/python3.8/distutils/dist.py", line 985, in run_command
cmd_obj.run()
File "/usr/lib/python3/dist-packages/wheel/bdist_wheel.py", line 223, in run
self.run_command('build')
File "/usr/lib/python3.8/distutils/cmd.py", line 313, in run_command
self.distribution.run_command(command)
File "/usr/lib/python3.8/distutils/dist.py", line 985, in run_command
cmd_obj.run()
File "/usr/lib/python3.8/distutils/command/build.py", line 135, in run
self.run_command(cmd_name)
File "/usr/lib/python3.8/distutils/cmd.py", line 313, in run_command
self.distribution.run_command(command)
File "/usr/lib/python3.8/distutils/dist.py", line 985, in run_command
cmd_obj.run()
File "/tmp/pip-install-t7al85w7/onnx/setup.py", line 209, in run
self.run_command('cmake_build')
File "/usr/lib/python3.8/distutils/cmd.py", line 313, in run_command
self.distribution.run_command(command)
File "/usr/lib/python3.8/distutils/dist.py", line 985, in run_command
cmd_obj.run()
File "/tmp/pip-install-t7al85w7/onnx/setup.py", line 203, in run
subprocess.check_call(build_args)
File "/usr/lib/python3.8/subprocess.py", line 364, in check_call
raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command '['/usr/bin/cmake', '--build', '.', '--', '-j', '12']' returned non-zero exit status 2.
----------------------------------------
ERROR: Failed building wheel for onnx
Running setup.py clean for onnx
Failed to build onnx
Installing collected packages: onnx
Running setup.py install for onnx ... error
ERROR: Command errored out with exit status 1:
command: /usr/bin/python3 -u -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'/tmp/pip-install-t7al85w7/onnx/setup.py'"'"'; __file__='"'"'/tmp/pip-install-t7al85w7/onnx/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' install --record /tmp/pip-record-b60n_z7m/install-record.txt --single-version-externally-managed --compile --install-headers /usr/local/include/python3.8/onnx
cwd: /tmp/pip-install-t7al85w7/onnx/
Complete output (107 lines):
fatal: not a git repository (or any of the parent directories): .git
running install
running build
running build_py
running create_version
running cmake_build
Generated: /tmp/pip-install-t7al85w7/onnx/.setuptools-cmake-build/onnx/onnx-ml.proto
Generated: /tmp/pip-install-t7al85w7/onnx/.setuptools-cmake-build/onnx/onnx-operators-ml.proto
CMake Warning at CMakeLists.txt:394 (find_package):
By not providing "Findpybind11.cmake" in CMAKE_MODULE_PATH this project has
asked CMake to find a package configuration file provided by "pybind11",
but CMake did not find one.
Could not find a package configuration file provided by "pybind11"
(requested version 2.2) with any of the following names:
pybind11Config.cmake
pybind11-config.cmake
Add the installation prefix of "pybind11" to CMAKE_PREFIX_PATH or set
"pybind11_DIR" to a directory containing one of the above files. If
"pybind11" provides a separate development package or SDK, be sure it has
been installed.
--
-- ******** Summary ********
-- CMake version : 3.16.3
-- CMake command : /usr/bin/cmake
-- System : Linux
-- C++ compiler : /usr/bin/c++
-- C++ compiler version : 9.3.0
-- CXX flags : -Wnon-virtual-dtor
-- Build type : Release
-- Compile definitions :
-- CMAKE_PREFIX_PATH :
-- CMAKE_INSTALL_PREFIX : /usr/local
-- CMAKE_MODULE_PATH :
--
-- ONNX version : 1.6.0
-- ONNX NAMESPACE : onnx
-- ONNX_BUILD_TESTS : OFF
-- ONNX_BUILD_BENCHMARKS : OFF
-- ONNX_USE_LITE_PROTO : OFF
-- ONNXIFI_DUMMY_BACKEND : OFF
-- ONNXIFI_ENABLE_EXT : OFF
--
-- Protobuf compiler : /usr/bin/protoc
-- Protobuf includes : /usr/include
-- Protobuf libraries : /usr/lib/x86_64-linux-gnu/libprotobuf.so;-lpthread
-- BUILD_ONNX_PYTHON : ON
-- Python version :
-- Python executable : /usr/bin/python3
-- Python includes : /usr/include/python3.8
-- Configuring done
-- Generating done
-- Build files have been written to: /tmp/pip-install-t7al85w7/onnx/.setuptools-cmake-build
[ 1%] Running C++ protocol buffer compiler on /tmp/pip-install-t7al85w7/onnx/.setuptools-cmake-build/onnx/onnx-ml.proto
[ 4%] Built target onnxifi_dummy
[ 8%] Built target onnxifi_loader
Scanning dependencies of target onnxifi_wrapper
/usr/bin/env: ‘python’: No such file or directory
--mypy_out: protoc-gen-mypy: Plugin failed with status code 127.
make[2]: *** [CMakeFiles/gen_onnx_proto.dir/build.make:62: onnx/onnx-ml.pb.cc] Error 1
make[1]: *** [CMakeFiles/Makefile2:250: CMakeFiles/gen_onnx_proto.dir/all] Error 2
make[1]: *** Waiting for unfinished jobs....
[ 9%] Building C object CMakeFiles/onnxifi_wrapper.dir/onnx/onnxifi_wrapper.c.o
[ 11%] Linking C shared module libonnxifi.so
[ 11%] Built target onnxifi_wrapper
make: *** [Makefile:130: all] Error 2
Traceback (most recent call last):
File "<string>", line 1, in <module>
File "/tmp/pip-install-t7al85w7/onnx/setup.py", line 315, in <module>
setuptools.setup(
File "/usr/lib/python3/dist-packages/setuptools/__init__.py", line 144, in setup
return distutils.core.setup(**attrs)
File "/usr/lib/python3.8/distutils/core.py", line 148, in setup
dist.run_commands()
File "/usr/lib/python3.8/distutils/dist.py", line 966, in run_commands
self.run_command(cmd)
File "/usr/lib/python3.8/distutils/dist.py", line 985, in run_command
cmd_obj.run()
File "/usr/lib/python3/dist-packages/setuptools/command/install.py", line 61, in run
return orig.install.run(self)
File "/usr/lib/python3.8/distutils/command/install.py", line 589, in run
self.run_command('build')
File "/usr/lib/python3.8/distutils/cmd.py", line 313, in run_command
self.distribution.run_command(command)
File "/usr/lib/python3.8/distutils/dist.py", line 985, in run_command
cmd_obj.run()
File "/usr/lib/python3.8/distutils/command/build.py", line 135, in run
self.run_command(cmd_name)
File "/usr/lib/python3.8/distutils/cmd.py", line 313, in run_command
self.distribution.run_command(command)
File "/usr/lib/python3.8/distutils/dist.py", line 985, in run_command
cmd_obj.run()
File "/tmp/pip-install-t7al85w7/onnx/setup.py", line 209, in run
self.run_command('cmake_build')
File "/usr/lib/python3.8/distutils/cmd.py", line 313, in run_command
self.distribution.run_command(command)
File "/usr/lib/python3.8/distutils/dist.py", line 985, in run_command
cmd_obj.run()
File "/tmp/pip-install-t7al85w7/onnx/setup.py", line 203, in run
subprocess.check_call(build_args)
File "/usr/lib/python3.8/subprocess.py", line 364, in check_call
raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command '['/usr/bin/cmake', '--build', '.', '--', '-j', '12']' returned non-zero exit status 2.
----------------------------------------
ERROR: Command errored out with exit status 1: /usr/bin/python3 -u -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'/tmp/pip-install-t7al85w7/onnx/setup.py'"'"'; __file__='"'"'/tmp/pip-install-t7al85w7/onnx/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' install --record /tmp/pip-record-b60n_z7m/install-record.txt --single-version-externally-managed --compile --install-headers /usr/local/include/python3.8/onnx Check the logs for full command output.
To circumvent this issue a symbolic link can be made so that the python command actually runs python3.

Answer 1

In summary, to install onnx successfully in Ubuntu 20.04, you'll need to:
1) Install protobuf-compiler: sudo apt install protobuf-compiler
2) Make a link from python3 to python: sudo ln -s /usr/bin/python3 /usr/bin/python
Note: Maybe I missed another dependency, I already installed a bunch of other packages while installing the OpenVINO dependencies.

Answer 2

Just validated the tips from tgonzaleza on Ubuntu 18.04.
After this fix, below error was displayed:
Could NOT find Protobuf (missing: Protobuf_INCLUDE_DIR)
Can be fixed with this:
sudo apt-get install libprotobuf-dev

Answer 3

In summary, to install onnx successfully in Ubuntu 20.04, you'll need to install this version of onnx
pip install onnx==1.4.1
goodluck