Add before_build option, that runs a shell command before 'pip wheel'

cibuildwheel/__main__.py

@@ -3,6 +3,24 @@ import argparse, os, subprocess, sys
 
 from cibuildwheel import linux, windows, macos
 
+def get_option_from_environment(option_name, platform=None):
+    '''
+    Returns an option from the environment, optionally scoped by the platform.
+
+    Example:
+      get_option_from_environment('CIBW_COLOR', platform='macos')
+
+      This will return the value of CIBW_COLOR_MACOS if it exists, otherwise the value of
+      CIBW_COLOR.
+    '''
+    if platform:
+        option = os.environ.get('%s_%s' % (option_name, platform.upper()))
+        if option is not None:
+            return option
+
+    return os.environ.get(option_name)
+
+
 def main():
     parser = argparse.ArgumentParser(
         description='Build wheels for all the platforms.',
@@ -29,10 +47,28 @@ def main():
 
     args = parser.parse_args()
 
+    if args.platform != 'auto':
+        platform = args.platform
+    else:
+        if os.environ.get('TRAVIS_OS_NAME') == 'linux':
+            platform = 'linux'
+        elif os.environ.get('TRAVIS_OS_NAME') == 'osx':
+            platform = 'macos'
+        elif 'APPVEYOR' in os.environ:
+            platform = 'windows'
+        else:
+            print('Unable to detect platform. cibuildwheel should run on your CI server, '
+                  'Travis CI and Appveyor are supported. You can run on your development '
+                  'machine using the --platform argument. Check --help output for more '
+                  'information.',
+                  file=sys.stderr)
+            exit(2)
+
     output_dir = args.output_dir
     test_command = os.environ.get('CIBW_TEST_COMMAND', None)
     test_requires = os.environ.get('CIBW_TEST_REQUIRES', '').split()
     project_dir = args.project_dir
+    before_build = get_option_from_environment('CIBW_BEFORE_BUILD', platform=platform)
 
     try:
         project_setup_py = os.path.join(project_dir, 'setup.py')
@@ -58,26 +94,10 @@ def main():
         package_name=package_name,
         output_dir=output_dir,
         test_command=test_command,
-        test_requires=test_requires
+        test_requires=test_requires,
+        before_build=before_build,
     )
 
-    if args.platform != 'auto':
-        platform = args.platform
-    else:
-        if os.environ.get('TRAVIS_OS_NAME') == 'linux':
-            platform = 'linux'
-        elif os.environ.get('TRAVIS_OS_NAME') == 'osx':
-            platform = 'macos'
-        elif 'APPVEYOR' in os.environ:
-            platform = 'windows'
-        else:
-            print('Unable to detect platform. cibuildwheel should run on your CI server, '
-                  'Travis CI and Appveyor are supported. You can run on your development '
-                  'machine using the --platform argument. Check --help output for more '
-                  'information.',
-                  file=sys.stderr)
-            exit(2)
-
     if platform == 'linux':
         linux.build(**build_args)
     elif platform == 'windows':

cibuildwheel/linux.py

@@ -1,5 +1,6 @@
 from __future__ import print_function
 import os, subprocess
+from .util import prepare_command
 
 try:
     from shlex import quote as shlex_quote
@@ -7,7 +8,7 @@ except ImportError:
     from pipes import quote as shlex_quote
 
 
-def build(project_dir, package_name, output_dir, test_command, test_requires):
+def build(project_dir, package_name, output_dir, test_command, test_requires, before_build):
     for docker_image in ['quay.io/pypa/manylinux1_x86_64', 'quay.io/pypa/manylinux1_i686']:
         bash_script = '''
             set -o errexit
@@ -15,6 +16,10 @@ def build(project_dir, package_name, output_dir, test_command, test_requires):
             cd /project
 
             for PYBIN in /opt/python/*/bin; do
+                if [ ! -z {before_build} ]; then
+                    PATH=$PYBIN:$PATH sh -c {before_build}
+                fi
+
                 "$PYBIN/pip" wheel . -w /tmp/linux_wheels
             done
 
@@ -42,7 +47,12 @@ def build(project_dir, package_name, output_dir, test_command, test_requires):
         '''.format(
             package_name=package_name,
             test_requires=' '.join(test_requires),
-            test_command=shlex_quote(test_command.format(project='/project') if test_command else ''),
+            test_command=shlex_quote(
+                test_command.format(project='/project') if test_command else ''
+            ),
+            before_build=shlex_quote(
+                prepare_command(before_build, python='python', pip='pip') if before_build else ''
+            ),
         )
 
         docker_process = subprocess.Popen([

cibuildwheel/macos.py

@@ -7,8 +7,10 @@ try:
 except ImportError:
     from pipes import quote as shlex_quote
 
+from .util import prepare_command
 
-def build(project_dir, package_name, output_dir, test_command, test_requires):
+
+def build(project_dir, package_name, output_dir, test_command, test_requires, before_build):
     PythonConfiguration = namedtuple('PythonConfiguration', ['version', 'url'])
     python_configurations = [
         PythonConfiguration(version='2.7', url='https://www.python.org/ftp/python/2.7.13/python-2.7.13-macosx10.6.pkg'),
@@ -47,6 +49,11 @@ def build(project_dir, package_name, output_dir, test_command, test_requires):
         shell([pip, 'install', 'wheel'], env=env)
         shell([pip, 'install', 'delocate'], env=env)
 
+        # run the before_build command
+        if before_build:
+            before_build_prepared = prepare_command(before_build, python=python, pip=pip)
+            shell(shlex.split(before_build_prepared), env=env)
+
         # build the wheel to temp dir
         temp_wheel_dir = '/tmp/tmpwheel%s' % config.version
         shell([pip, 'wheel', project_dir, '-w', temp_wheel_dir], env=env)

cibuildwheel/util.py

@@ -0,0 +1,11 @@
+
+def prepare_command(command, python, pip):
+    '''
+    Preprocesses a command by expanding variables like {python} or {pip}.
+
+    For example, used for the before_build option, where the user would
+    like to run a command like `python setup.py test`. If the command should run on
+    Python 3, the user could write `{python} setup.py test`. This command would expand
+    it out to python2 or python3 as appropriate.
+    '''
+    return command.format(python=python, pip=pip)

cibuildwheel/windows.py

@@ -2,8 +2,10 @@ from __future__ import print_function
 import os, tempfile, subprocess, urllib2
 from collections import namedtuple
 
+from .util import prepare_command
 
-def build(project_dir, package_name, output_dir, test_command, test_requires):
+
+def build(project_dir, package_name, output_dir, test_command, test_requires, before_build):
     # run_with_env is a cmd file that sets the right environment variables to
     run_with_env = os.path.join(tempfile.gettempdir(), 'appveyor_run_with_env.cmd')
     if not os.path.exists(run_with_env):
@@ -51,6 +53,11 @@ def build(project_dir, package_name, output_dir, test_command, test_requires):
               env=env)
         shell(['pip', 'install', 'wheel'], env=env)
 
+        # run the before_build command
+        if before_build:
+            before_build_prepared = prepare_command(before_build, python='python', pip='pip')
+            shell([before_build_prepared], env=env)
+
         # build the wheel
         shell(['pip', 'wheel', project_dir, '-w', output_dir], env=env)