Make configure script runnable from external workspace. (tensorflow#17172)

To run from external workspace, you should now be able to invoke
script like the following. This will generate some TensorFlow specfic
bazel options and import them into your project's .bazelrc.

$(bazel info output_base)/external/org_tensorflow/configure.py --workspace=$(PWD)

Author: Michael Case

configure

@@ -8,7 +8,8 @@ if [ -z "$PYTHON_BIN_PATH" ]; then
 fi
 
 # Set all env variables
-"$PYTHON_BIN_PATH" configure.py
+CONFIGURE_DIR=$(dirname "$0")
+"$PYTHON_BIN_PATH" "${CONFIGURE_DIR}/configure.py" "$@"
 
 echo "Configuration finished"
 

configure.py

@@ -18,6 +18,7 @@
 from __future__ import division
 from __future__ import print_function
 
+import argparse
 import errno
 import os
 import platform
@@ -32,10 +33,6 @@
   from distutils.spawn import find_executable as which
 # pylint: enable=g-import-not-at-top
 
-_TF_BAZELRC = os.path.join(os.path.dirname(os.path.abspath(__file__)),
-                           '.tf_configure.bazelrc')
-_TF_WORKSPACE = os.path.join(os.path.dirname(os.path.abspath(__file__)),
-                             'WORKSPACE')
 _DEFAULT_CUDA_VERSION = '9.0'
 _DEFAULT_CUDNN_VERSION = '7'
 _DEFAULT_CUDA_COMPUTE_CAPABILITIES = '3.5,5.2'
@@ -51,6 +48,11 @@
 
 _DEFAULT_PROMPT_ASK_ATTEMPTS = 10
 
+_TF_WORKSPACE_ROOT = os.path.abspath(os.path.dirname(__file__))
+_TF_BAZELRC_FILENAME = '.tf_configure.bazelrc'
+_TF_BAZELRC = os.path.join(_TF_WORKSPACE_ROOT, _TF_BAZELRC_FILENAME)
+_TF_WORKSPACE = os.path.join(_TF_WORKSPACE_ROOT, 'WORKSPACE')
+
 
 class UserInputError(Exception):
   pass
@@ -119,22 +121,6 @@ def sed_in_place(filename, old, new):
     f.write(newdata)
 
 
-def remove_line_with(filename, token):
-  """Remove lines that contain token from file.
-
-  Args:
-    filename: string for filename.
-    token: string token to check if to remove a line from file or not.
-  """
-  with open(filename, 'r') as f:
-    filedata = f.read()
-
-  with open(filename, 'w') as f:
-    for line in filedata.strip().split('\n'):
-      if token not in line:
-        f.write(line + '\n')
-
-
 def write_to_bazelrc(line):
   with open(_TF_BAZELRC, 'a') as f:
     f.write(line + '\n')
@@ -245,33 +231,35 @@ def setup_python(environ_cp):
   environ_cp['PYTHON_BIN_PATH'] = python_bin_path
 
   # Write tools/python_bin_path.sh
-  with open('tools/python_bin_path.sh', 'w') as f:
+  with open(os.path.join(
+      _TF_WORKSPACE_ROOT, 'tools', 'python_bin_path.sh'), 'w') as f:
     f.write('export PYTHON_BIN_PATH="%s"' % python_bin_path)
 
 
-def reset_tf_configure_bazelrc():
+def reset_tf_configure_bazelrc(workspace_path):
   """Reset file that contains customized config settings."""
   open(_TF_BAZELRC, 'w').close()
+  bazelrc_path = os.path.join(workspace_path, '.bazelrc')
 
-  home = os.path.expanduser('~')
-  if not os.path.exists('.bazelrc'):
-    if os.path.exists(os.path.join(home, '.bazelrc')):
-      with open('.bazelrc', 'a') as f:
-        f.write('import %s/.bazelrc\n' % home.replace('\\', '/'))
-    else:
-      open('.bazelrc', 'w').close()
-
-  remove_line_with('.bazelrc', 'tf_configure')
-  with open('.bazelrc', 'a') as f:
-    f.write('import %workspace%/.tf_configure.bazelrc\n')
+  data = []
+  if os.path.exists(bazelrc_path):
+    with open(bazelrc_path, 'r') as f:
+      data = f.read().splitlines()
+  with open(bazelrc_path, 'w') as f:
+    for l in data:
+      if _TF_BAZELRC_FILENAME in l:
+        continue
+      f.write('%s\n' % l)
+    f.write('import %s\n' % _TF_BAZELRC)
 
 
 def cleanup_makefile():
   """Delete any leftover BUILD files from the Makefile build.
 
   These files could interfere with Bazel parsing.
   """
-  makefile_download_dir = 'tensorflow/contrib/makefile/downloads'
+  makefile_download_dir = os.path.join(
+      _TF_WORKSPACE_ROOT, 'tensorflow', 'contrib', 'makefile', 'downloads')
   if os.path.isdir(makefile_download_dir):
     for root, _, filenames in os.walk(makefile_download_dir):
       for f in filenames:
@@ -1373,13 +1361,20 @@ def config_info_line(name, help_text):
 
 
 def main():
+  parser = argparse.ArgumentParser()
+  parser.add_argument("--workspace",
+                      type=str,
+                      default=_TF_WORKSPACE_ROOT,
+                      help="The absolute path to your active Bazel workspace.")
+  args = parser.parse_args()
+
   # Make a copy of os.environ to be clear when functions and getting and setting
   # environment variables.
   environ_cp = dict(os.environ)
 
   check_bazel_version('0.5.4')
 
-  reset_tf_configure_bazelrc()
+  reset_tf_configure_bazelrc(args.workspace)
   cleanup_makefile()
   setup_python(environ_cp)