cache cwd in config object, handle os.getcwd errors

Author: oesteban

nipype/utils/config.py

@@ -15,7 +15,6 @@
 import errno
 import atexit
 from warnings import warn
-from io import StringIO
 from distutils.version import LooseVersion
 import configparser
 import numpy as np
@@ -37,21 +36,19 @@
 
 NUMPY_MMAP = LooseVersion(np.__version__) >= LooseVersion('1.12.0')
 
-# Get home directory in platform-agnostic way
-homedir = os.path.expanduser('~')
-default_cfg = """
+DEFAULT_CONFIG_TPL = """\
 [logging]
 workflow_level = INFO
 utils_level = INFO
 interface_level = INFO
 log_to_file = false
-log_directory = %s
+log_directory = {log_dir}
 log_size = 16384000
 log_rotate = 4
 
 [execution]
 create_report = true
-crashdump_dir = %s
+crashdump_dir = {crashdump_dir}
 hash_method = timestamp
 job_finished_timeout = 5
 keep_inputs = false
@@ -79,7 +76,7 @@
 
 [check]
 interval = 1209600
-""" % (homedir, os.getcwd())
+""".format
 
 
 def mkdir_p(path):
@@ -97,15 +94,17 @@ class NipypeConfig(object):
 
     def __init__(self, *args, **kwargs):
         self._config = configparser.ConfigParser()
+        self._cwd = None
+
         config_dir = os.path.expanduser('~/.nipype')
-        config_file = os.path.join(config_dir, 'nipype.cfg')
         self.data_file = os.path.join(config_dir, 'nipype.json')
-        self._config.readfp(StringIO(default_cfg))
+
+        self.set_default_config()
         self._display = None
         self._resource_monitor = None
 
         if os.path.exists(config_dir):
-            self._config.read([config_file, 'nipype.cfg'])
+            self._config.read([os.path.join(config_dir, 'nipype.cfg'), 'nipype.cfg'])
 
         for option in CONFIG_DEPRECATIONS:
             for section in ['execution', 'logging', 'monitoring']:
@@ -115,8 +114,32 @@ def __init__(self, *args, **kwargs):
                         # Warn implicit in get
                         self.set(new_section, new_option, self.get(section, option))
 
+    @property
+    def cwd(self):
+        """Cache current working directory ASAP"""
+        # Run getcwd only once, preventing multiproc to finish
+        # with error having changed to the wrong path
+        if self._cwd is None:
+            try:
+                self._cwd = os.getcwd()
+            except OSError:
+                warn('Trying to run Nipype from a nonexistent directory "%s".',
+                     os.getenv('PWD', 'unknown'))
+                raise
+        return self._cwd
+
     def set_default_config(self):
-        self._config.readfp(StringIO(default_cfg))
+        """Read default settings template and set into config object"""
+        default_cfg = DEFAULT_CONFIG_TPL(
+            log_dir=os.path.expanduser('~'),  # Get $HOME in a platform-agnostic way
+            crashdump_dir=self.cwd  # Read cached cwd
+        )
+
+        try:
+            self._config.read_string(default_cfg)  # Python >= 3.2
+        except AttributeError:
+            from io import StringIO
+            self._config.readfp(StringIO(default_cfg))
 
     def enable_debug_mode(self):
         """Enables debug configuration"""