Build Horovod with temporarily installed CMake if necessary

Dockerfile.test.cpu

@@ -36,6 +36,7 @@ RUN add-apt-repository ppa:ubuntu-toolchain-r/test
 RUN apt-get update -qq && apt-get install -y --no-install-recommends \
         wget \
         ca-certificates \
+        cmake \
         openssh-client \
         openssh-server \
         git \
@@ -57,9 +58,6 @@ RUN wget --progress=dot:mega https://bootstrap.pypa.io/get-pip.py && python get-
 # https://github.com/pytorch/pytorch/issues/72045
 RUN pip install --no-cache-dir -U --force pip~=21.0.0 setuptools requests pytest mock pytest-forked parameterized
 
-# Install recent CMake.
-RUN pip install --no-cache-dir -U cmake~=3.13.0
-
 # Add launch helper scripts
 RUN echo "env SPARK_HOME=/spark SPARK_DRIVER_MEM=512m PYSPARK_PYTHON=/usr/bin/python${PYTHON_VERSION} PYSPARK_DRIVER_PYTHON=/usr/bin/python${PYTHON_VERSION} \"\$@\"" > /spark_env.sh
 RUN echo /spark_env.sh pytest -v --capture=no --continue-on-collection-errors --junit-xml=/artifacts/junit.\$1.\${HOROVOD_RANK:-\${OMPI_COMM_WORLD_RANK:-\${PMI_RANK}}}.\$2.xml \${@:2} > /pytest.sh

Dockerfile.test.gpu

@@ -38,6 +38,7 @@ RUN CUDNN_MAJOR=$(cut -d '.' -f 1 <<< "${CUDNN_VERSION}"); \
     apt-get update -qq && apt-get install -y --allow-downgrades --allow-change-held-packages --no-install-recommends \
         wget \
         ca-certificates \
+        cmake \
         openssh-client \
         openssh-server \
         git \
@@ -62,9 +63,6 @@ RUN wget --progress=dot:mega https://bootstrap.pypa.io/get-pip.py && python get-
 # https://github.com/pytorch/pytorch/issues/72045
 RUN pip install --no-cache-dir -U --force pip~=21.0.0 "setuptools<60.1.0" requests pytest mock pytest-forked parameterized
 
-# Install recent CMake.
-RUN pip install --no-cache-dir -U cmake~=3.13.0
-
 # Add launch helper scripts
 RUN echo "env SPARK_HOME=/spark SPARK_DRIVER_MEM=512m PYSPARK_PYTHON=/usr/bin/python${PYTHON_VERSION} PYSPARK_DRIVER_PYTHON=/usr/bin/python${PYTHON_VERSION} \"\$@\"" > /spark_env.sh
 RUN echo /spark_env.sh pytest -v --capture=no --continue-on-collection-errors --junit-xml=/artifacts/junit.\$1.\${HOROVOD_RANK:-\${OMPI_COMM_WORLD_RANK:-\${PMI_RANK}}}.\$2.xml \${@:2} > /pytest.sh

docker-compose.test.yml

@@ -59,6 +59,7 @@ services:
       args:
         # Tensorflow 1.15.5 is only available for Python 3.7
         # Python 3.7 is only available on Ubuntu 18.04
+        # On Ubuntu 18.04 our setup.py will pull in a recent CMake and use that only to build Horovod
         UBUNTU_VERSION: 18.04
         PYTHON_VERSION: 3.7
         # there is no tensorflow-cpu>1.15.0, so we use tensorflow==1.15.5

docker/horovod-cpu/Dockerfile

@@ -17,9 +17,9 @@ SHELL ["/bin/bash", "-euo", "pipefail", "-c"]
 
 RUN apt-get update && apt-get install -y --allow-downgrades --allow-change-held-packages --no-install-recommends \
         build-essential \
+        cmake \
         g++-7 \
         git \
-        gpg \
         curl \
         vim \
         wget \
@@ -56,9 +56,6 @@ RUN curl -O https://bootstrap.pypa.io/get-pip.py && \
     python get-pip.py && \
     rm get-pip.py
 
-# Install recent CMake.
-RUN pip install --no-cache-dir -U cmake~=3.13.0
-
 # Install PyTorch, TensorFlow, Keras and MXNet
 RUN pip install --no-cache-dir torch==${PYTORCH_VERSION} torchvision==${TORCHVISION_VERSION}
 RUN pip install --no-cache-dir pytorch_lightning==${PYTORCH_LIGHTNING_VERSION}

docker/horovod-ray/Dockerfile

@@ -15,17 +15,14 @@ SHELL ["/bin/bash", "-euo", "pipefail", "-c"]
 
 RUN sudo apt-get update && DEBIAN_FRONTEND="noninteractive" sudo apt-get install -y \
         build-essential \
+        cmake \
         wget \
         git \
-        gpg \
         curl \
         rsync \
         vim \
     && sudo apt-get clean && sudo rm -rf /var/lib/apt/lists/*
 
-# Install recent CMake.
-RUN pip install --no-cache-dir -U cmake~=3.13.0
-
 # Install PyTorch
 RUN pip install --no-cache-dir \
     torch==${PYTORCH_VERSION} \

docker/horovod/Dockerfile

@@ -23,9 +23,9 @@ SHELL ["/bin/bash", "-euo", "pipefail", "-c"]
 
 RUN apt-get update && apt-get install -y --allow-downgrades --allow-change-held-packages --no-install-recommends \
         build-essential \
+        cmake \
         g++-7 \
         git \
-        gpg \
         curl \
         vim \
         wget \
@@ -68,9 +68,6 @@ RUN curl -O https://bootstrap.pypa.io/get-pip.py && \
     rm get-pip.py && \
     pip install --no-cache-dir -U --force pip~=21.0.0
 
-# Install recent CMake.
-RUN pip install --no-cache-dir -U cmake~=3.13.0
-
 # Install PyTorch, TensorFlow, Keras and MXNet
 RUN pip install --no-cache-dir \
     torch==${PYTORCH_VERSION} \

docs/install.rst

@@ -17,8 +17,9 @@ For best performance on GPU:
 
 - `NCCL 2 <https://developer.nvidia.com/nccl>`__
 
-If Horovod in unable to find the CMake binary, you may need to set ``HOROVOD_CMAKE`` in your environment before
-installing.
+If Horovod cannot find CMake 3.13 or newer, the build script will attempt to pull in a recent CMake binary and run it
+from a temporary location.  To select a specific binary you can also set ``HOROVOD_CMAKE`` in your environment before
+installing Horovod.
 
 Horovod does not support Windows.
 
@@ -246,7 +247,7 @@ Possible values are given in curly brackets: {}.
 * ``HOROVOD_GPU_BROADCAST`` - {NCCL, MPI}. Framework to use for GPU tensor broadcast.
 * ``HOROVOD_ALLOW_MIXED_GPU_IMPL`` - {1}. Allow Horovod to install with NCCL allreduce and MPI GPU allgather / broadcast.  Not recommended due to a possible deadlock.
 * ``HOROVOD_CPU_OPERATIONS`` - {MPI, GLOO, CCL}. Framework to use for CPU tensor allreduce, allgather, and broadcast.
-* ``HOROVOD_CMAKE`` - path to the CMake binary used to build Gloo (not required when using MPI).
+* ``HOROVOD_CMAKE`` - path to the CMake binary used to build Horovod.
 * ``HOROVOD_WITH_TENSORFLOW`` - {1}. Require Horovod to install with TensorFlow support enabled.
 * ``HOROVOD_WITHOUT_TENSORFLOW`` - {1}. Skip installing TensorFlow support.
 * ``HOROVOD_WITH_PYTORCH`` - {1}. Require Horovod to install with PyTorch support enabled.

setup.py

@@ -15,14 +15,19 @@
 # limitations under the License.
 # ==============================================================================
 
+import atexit
+import io
 import os
+import re
 import shutil
 import subprocess
 import sys
+import tempfile
 import textwrap
 
 from setuptools import setup, Extension, find_packages
 from setuptools.command.build_ext import build_ext
+from distutils.version import LooseVersion
 
 from horovod import __version__
 
@@ -60,7 +65,34 @@ def is_build_action():
         return True
 
 def get_cmake_bin():
-    return os.environ.get('HOROVOD_CMAKE', 'cmake')
+    if 'HOROVOD_CMAKE' in os.environ:
+        return os.environ['HOROVOD_CMAKE']
+
+    cmake_bin = 'cmake'
+    try:
+        out = subprocess.check_output([cmake_bin, '--version'])
+    except OSError:
+        cmake_installed_version = LooseVersion("0.0")
+    else:
+        cmake_installed_version = LooseVersion(re.search(r'version\s*([\d.]+)', out.decode()).group(1))
+
+    if cmake_installed_version < LooseVersion("3.13.0"):
+        print("Could not find a recent CMake to build Horovod. "
+              "Attempting to install CMake 3.13 to a temporary location via pip.", flush=True)
+        cmake_temp_dir = tempfile.TemporaryDirectory(prefix="horovod-cmake-tmp")
+        atexit.register(cmake_temp_dir.cleanup)
+        try:
+            _ = subprocess.check_output(["pip", "install", "--target", cmake_temp_dir.name, "cmake~=3.13.0"])
+        except Exception:
+            raise RuntimeError("Failed to install temporary CMake. "
+                               "Please update your CMake to 3.13+ or set HOROVOD_CMAKE appropriately.")
+        cmake_bin = os.path.join(cmake_temp_dir.name, "bin", "run_cmake")
+        with io.open(cmake_bin, "w") as f_run_cmake:
+            f_run_cmake.write(
+                f"#!/bin/sh\nPYTHONPATH={cmake_temp_dir.name} {os.path.join(cmake_temp_dir.name, 'bin', 'cmake')} \"$@\"")
+        os.chmod(cmake_bin, 0o755)
+
+    return cmake_bin
 
 
 class custom_build_ext(build_ext):
@@ -103,7 +135,7 @@ def build_extensions(self):
         if self.verbose:
             print(f"Running CMake in {cmake_build_dir}:")
             for command in config_and_build_commands:
-	            print(" ".join(command))
+                print(" ".join(command))
             sys.stdout.flush()
 
         # Config and build the extension