Add python_configure.bzl to provide python headers.
diff --git a/py/BUILD b/py/BUILD new file mode 100644 index 0000000..e69de29 --- /dev/null +++ b/py/BUILD
diff --git a/py/BUILD.tpl b/py/BUILD.tpl new file mode 100644 index 0000000..8bd1374 --- /dev/null +++ b/py/BUILD.tpl
@@ -0,0 +1,68 @@ +licenses(["restricted"]) + +package(default_visibility = ["//visibility:public"]) + +# Point both runtimes to the same python binary to ensure we always +# use the python binary specified by ./configure.py script. +load("@bazel_tools//tools/python:toolchain.bzl", "py_runtime_pair") + +py_runtime( + name = "py2_runtime", + interpreter_path = "%{PYTHON_BIN_PATH}", + python_version = "PY2", +) + +py_runtime( + name = "py3_runtime", + interpreter_path = "%{PYTHON_BIN_PATH}", + python_version = "PY3", +) + +py_runtime_pair( + name = "py_runtime_pair", + py2_runtime = ":py2_runtime", + py3_runtime = ":py3_runtime", +) + +toolchain( + name = "py_toolchain", + toolchain = ":py_runtime_pair", + toolchain_type = "@bazel_tools//tools/python:toolchain_type", +) + +# To build Python C/C++ extension on Windows, we need to link to python import library pythonXY.lib +# See https://docs.python.org/3/extending/windows.html +cc_import( + name = "python_lib", + interface_library = select({ + ":windows": ":python_import_lib", + # A placeholder for Unix platforms which makes --no_build happy. + "//conditions:default": "not-existing.lib", + }), + system_provided = 1, +) + +cc_library( + name = "python_headers", + hdrs = [":python_include"], + deps = select({ + ":windows": [":python_lib"], + "//conditions:default": [], + }), + includes = ["python_include"], +) + +cc_library( + name = "numpy_headers", + hdrs = [":numpy_include"], + includes = ["numpy_include"], +) + +config_setting( + name = "windows", + values = {"cpu": "x64_windows"}, + visibility = ["//visibility:public"], +) + +%{PYTHON_INCLUDE_GENRULE} +%{PYTHON_IMPORT_LIB_GENRULE}
diff --git a/python_configure.bzl b/python_configure.bzl new file mode 100644 index 0000000..ac41ef8 --- /dev/null +++ b/python_configure.bzl
@@ -0,0 +1,335 @@ +"""Repository rule for Python autoconfiguration. + +`python_configure` depends on the following environment variables: + + * `PYTHON_BIN_PATH`: location of python binary. + * `PYTHON_LIB_PATH`: Location of python libraries. +""" + +_BAZEL_SH = "BAZEL_SH" +_PYTHON_BIN_PATH = "PYTHON_BIN_PATH" +_PYTHON_LIB_PATH = "PYTHON_LIB_PATH" + +def _tpl(repository_ctx, tpl, substitutions = {}, out = None): + if not out: + out = tpl + repository_ctx.template( + out, + Label("//py:%s.tpl" % tpl), + substitutions, + ) + +def _fail(msg): + """Output failure message when auto configuration fails.""" + red = "\033[0;31m" + no_color = "\033[0m" + fail("%sPython Configuration Error:%s %s\n" % (red, no_color, msg)) + +def _is_windows(repository_ctx): + """Returns true if the host operating system is windows.""" + os_name = repository_ctx.os.name.lower() + if os_name.find("windows") != -1: + return True + return False + +def _execute( + repository_ctx, + cmdline, + error_msg = None, + error_details = None, + empty_stdout_fine = False): + """Executes an arbitrary shell command. + + Args: + repository_ctx: the repository_ctx object + cmdline: list of strings, the command to execute + error_msg: string, a summary of the error if the command fails + error_details: string, details about the error or steps to fix it + empty_stdout_fine: bool, if True, an empty stdout result is fine, otherwise + it's an error + Return: + the result of repository_ctx.execute(cmdline) + """ + result = repository_ctx.execute(cmdline) + if result.stderr or not (empty_stdout_fine or result.stdout): + _fail("\n".join([ + error_msg.strip() if error_msg else "Repository command failed", + result.stderr.strip(), + error_details if error_details else "", + ])) + return result + +def _read_dir(repository_ctx, src_dir): + """Returns a string with all files in a directory. + + Finds all files inside a directory, traversing subfolders and following + symlinks. The returned string contains the full path of all files + separated by line breaks. + """ + if _is_windows(repository_ctx): + src_dir = src_dir.replace("/", "\\") + find_result = _execute( + repository_ctx, + ["cmd.exe", "/c", "dir", src_dir, "/b", "/s", "/a-d"], + empty_stdout_fine = True, + ) + + # src_files will be used in genrule.outs where the paths must + # use forward slashes. + result = find_result.stdout.replace("\\", "/") + else: + find_result = _execute( + repository_ctx, + ["find", src_dir, "-follow", "-type", "f"], + empty_stdout_fine = True, + ) + result = find_result.stdout + return result + +def _genrule(src_dir, genrule_name, command, outs): + """Returns a string with a genrule. + + Genrule executes the given command and produces the given outputs. + """ + return ( + "genrule(\n" + + ' name = "' + + genrule_name + '",\n' + + " outs = [\n" + + outs + + "\n ],\n" + + ' cmd = """\n' + + command + + '\n """,\n' + + ")\n" + ) + +def _norm_path(path): + """Returns a path with '/' and remove the trailing slash.""" + path = path.replace("\\", "/") + if path[-1] == "/": + path = path[:-1] + return path + +def _symlink_genrule_for_dir( + repository_ctx, + src_dir, + dest_dir, + genrule_name, + src_files = [], + dest_files = []): + """Returns a genrule to symlink(or copy if on Windows) a set of files. + + If src_dir is passed, files will be read from the given directory; otherwise + we assume files are in src_files and dest_files + """ + if src_dir != None: + src_dir = _norm_path(src_dir) + dest_dir = _norm_path(dest_dir) + files = "\n".join(sorted(_read_dir(repository_ctx, src_dir).splitlines())) + + # Create a list with the src_dir stripped to use for outputs. + dest_files = files.replace(src_dir, "").splitlines() + src_files = files.splitlines() + command = [] + outs = [] + for i in range(len(dest_files)): + if dest_files[i] != "": + # If we have only one file to link we do not want to use the dest_dir, as + # $(@D) will include the full path to the file. + dest = "$(@D)/" + dest_dir + dest_files[i] if len(dest_files) != 1 else "$(@D)/" + dest_files[i] + + # Copy the headers to create a sandboxable setup. + cmd = "cp -f" + command.append(cmd + ' "%s" "%s"' % (src_files[i], dest)) + outs.append(' "' + dest_dir + dest_files[i] + '",') + genrule = _genrule( + src_dir, + genrule_name, + " && ".join(command), + "\n".join(outs), + ) + return genrule + +def _get_python_bin(repository_ctx): + """Gets the python bin path.""" + python_bin = repository_ctx.os.environ.get(_PYTHON_BIN_PATH) + if python_bin != None: + return python_bin + python_bin_path = repository_ctx.which("python") + if python_bin_path != None: + return str(python_bin_path) + _fail("Cannot find python in PATH, please make sure " + + "python is installed and add its directory in PATH, or --define " + + "%s='/something/else'.\nPATH=%s" % ( + _PYTHON_BIN_PATH, + repository_ctx.os.environ.get("PATH", ""), + )) + +def _get_bash_bin(repository_ctx): + """Gets the bash bin path.""" + bash_bin = repository_ctx.os.environ.get(_BAZEL_SH) + if bash_bin != None: + return bash_bin + else: + bash_bin_path = repository_ctx.which("bash") + if bash_bin_path != None: + return str(bash_bin_path) + else: + _fail("Cannot find bash in PATH, please make sure " + + "bash is installed and add its directory in PATH, or --define " + + "%s='/path/to/bash'.\nPATH=%s" % ( + _BAZEL_SH, + repository_ctx.os.environ.get("PATH", ""), + )) + +def _get_python_lib(repository_ctx, python_bin): + """Gets the python lib path.""" + python_lib = repository_ctx.os.environ.get(_PYTHON_LIB_PATH) + if python_lib != None: + return python_lib + print_lib = ("<<END\n" + + "from __future__ import print_function\n" + + "import site\n" + + "import os\n" + + "\n" + + "try:\n" + + " input = raw_input\n" + + "except NameError:\n" + + " pass\n" + + "\n" + + "python_paths = []\n" + + "if os.getenv('PYTHONPATH') is not None:\n" + + " python_paths = os.getenv('PYTHONPATH').split(':')\n" + + "try:\n" + + " library_paths = site.getsitepackages()\n" + + "except AttributeError:\n" + + " from distutils.sysconfig import get_python_lib\n" + + " library_paths = [get_python_lib()]\n" + + "all_paths = set(python_paths + library_paths)\n" + + "paths = []\n" + + "for path in all_paths:\n" + + " if os.path.isdir(path):\n" + + " paths.append(path)\n" + + "if len(paths) >=1:\n" + + " print(paths[0])\n" + + "END") + cmd = "%s - %s" % (python_bin, print_lib) + result = repository_ctx.execute([_get_bash_bin(repository_ctx), "-c", cmd]) + return result.stdout.strip("\n") + +def _check_python_lib(repository_ctx, python_lib): + """Checks the python lib path.""" + cmd = 'test -d "%s" -a -x "%s"' % (python_lib, python_lib) + result = repository_ctx.execute([_get_bash_bin(repository_ctx), "-c", cmd]) + if result.return_code == 1: + _fail("Invalid python library path: %s" % python_lib) + +def _check_python_bin(repository_ctx, python_bin): + """Checks the python bin path.""" + cmd = '[[ -x "%s" ]] && [[ ! -d "%s" ]]' % (python_bin, python_bin) + result = repository_ctx.execute([_get_bash_bin(repository_ctx), "-c", cmd]) + if result.return_code == 1: + _fail("--define %s='%s' is not executable. Is it the python binary?" % ( + _PYTHON_BIN_PATH, + python_bin, + )) + +def _get_python_include(repository_ctx, python_bin): + """Gets the python include path.""" + result = _execute( + repository_ctx, + [ + python_bin, + "-c", + "from __future__ import print_function;" + + "from distutils import sysconfig;" + + "print(sysconfig.get_python_inc())", + ], + error_msg = "Problem getting python include path.", + error_details = ("Is the Python binary path set up right? " + + "(See ./configure or " + _PYTHON_BIN_PATH + ".) " + + "Is distutils installed?"), + ) + return result.stdout.splitlines()[0] + +def _get_python_import_lib_name(repository_ctx, python_bin): + """Get Python import library name (pythonXY.lib) on Windows.""" + result = _execute( + repository_ctx, + [ + python_bin, + "-c", + "import sys;" + + 'print("python" + str(sys.version_info[0]) + ' + + ' str(sys.version_info[1]) + ".lib")', + ], + error_msg = "Problem getting python import library.", + error_details = ("Is the Python binary path set up right? " + + "(See ./configure or " + _PYTHON_BIN_PATH + ".) "), + ) + return result.stdout.splitlines()[0] + +def _create_local_python_repository(repository_ctx): + """Creates the repository containing files set up to build with Python.""" + python_bin = _get_python_bin(repository_ctx) + _check_python_bin(repository_ctx, python_bin) + python_lib = _get_python_lib(repository_ctx, python_bin) + _check_python_lib(repository_ctx, python_lib) + python_include = _get_python_include(repository_ctx, python_bin) + python_include_rule = _symlink_genrule_for_dir( + repository_ctx, + python_include, + "python_include", + "python_include", + ) + python_import_lib_genrule = "" + + # To build Python C/C++ extension on Windows, we need to link to python import library pythonXY.lib + # See https://docs.python.org/3/extending/windows.html + if _is_windows(repository_ctx): + python_include = _norm_path(python_include) + python_import_lib_name = _get_python_import_lib_name(repository_ctx, python_bin) + python_import_lib_src = python_include.rsplit("/", 1)[0] + "/libs/" + python_import_lib_name + python_import_lib_genrule = _symlink_genrule_for_dir( + repository_ctx, + None, + "", + "python_import_lib", + [python_import_lib_src], + [python_import_lib_name], + ) + _tpl(repository_ctx, "BUILD", { + "%{PYTHON_BIN_PATH}": python_bin, + "%{PYTHON_INCLUDE_GENRULE}": python_include_rule, + "%{PYTHON_IMPORT_LIB_GENRULE}": python_import_lib_genrule, + }) + +def _create_remote_python_repository(repository_ctx, remote_config_repo): + """Creates pointers to a remotely configured repo set up to build with Python. + """ + repository_ctx.template("BUILD", Label(remote_config_repo + ":BUILD"), {}) + +def _python_autoconf_impl(repository_ctx): + """Implementation of the python_autoconf repository rule.""" + _create_local_python_repository(repository_ctx) + +python_configure = repository_rule( + implementation = _python_autoconf_impl, + environ = [ + _BAZEL_SH, + _PYTHON_BIN_PATH, + _PYTHON_LIB_PATH, + ], +) +"""Detects and configures the local Python. + +Add the following to your WORKSPACE FILE: + +```python +python_configure(name = "local_config_python") +``` + +Args: + name: A unique name for this workspace rule. +"""