Use platform neutral line separator(s)

To at least try to support things like windows it's better
if we can make an attempt to use the platform neutral
characters for line separator(s) where appropriate.

Change-Id: Icc533ed4d4c94f461b7f19600b74146221f17b18

taskflow/engines/worker_based/worker.py

@@ -141,8 +141,13 @@ class Worker(object):
             pass
         tpl_params['platform'] = platform.platform()
         tpl_params['thread_id'] = tu.get_ident()
-        return BANNER_TEMPLATE.substitute(BANNER_TEMPLATE.defaults,
+        banner = BANNER_TEMPLATE.substitute(BANNER_TEMPLATE.defaults,
-                                          **tpl_params)
+                                            **tpl_params)
+        # NOTE(harlowja): this is needed since the template in this file
+        # will always have newlines that end with '\n' (even on different
+        # platforms due to the way this source file is encoded) so we have
+        # to do this little dance to make it platform neutral...
+        return misc.fix_newlines(banner)
 
     def run(self, display_banner=True, banner_writer=None):
         """Runs the worker."""

taskflow/exceptions.py

@@ -14,6 +14,7 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+import os
 import traceback
 
 import six
@@ -46,14 +47,19 @@ class TaskFlowException(Exception):
         """Pretty formats a taskflow exception + any connected causes."""
         if indent < 0:
             raise ValueError("indent must be greater than or equal to zero")
-        return "\n".join(self._pformat(self, [], 0,
+        return os.linesep.join(self._pformat(self, [], 0,
-                                       indent=indent, indent_text=indent_text))
+                                             indent=indent,
+                                             indent_text=indent_text))
 
     @classmethod
     def _pformat(cls, excp, lines, current_indent, indent=2, indent_text=" "):
         line_prefix = indent_text * current_indent
         for line in traceback.format_exception_only(type(excp), excp):
             # We'll add our own newlines on at the end of formatting.
+            #
+            # NOTE(harlowja): the reason we don't search for os.linesep is
+            # that the traceback module seems to only use '\n' (for some
+            # reason).
             if line.endswith("\n"):
                 line = line[0:-1]
             lines.append(line_prefix + line)

taskflow/listeners/claims.py

@@ -17,6 +17,7 @@
 from __future__ import absolute_import
 
 import logging
+import os
 
 import six
 
@@ -70,7 +71,8 @@ class CheckingClaimListener(base.Listener):
             engine.suspend()
         except exceptions.TaskFlowException as e:
             LOG.warn("Failed suspending engine '%s', (previously owned by"
-                     " '%s'):\n%s", engine, self._owner, e.pformat())
+                     " '%s'):%s%s", engine, self._owner, os.linesep,
+                     e.pformat())
 
     def _flow_receiver(self, state, details):
         self._claim_checker(state, details)

taskflow/listeners/logging.py

@@ -17,6 +17,7 @@
 from __future__ import absolute_import
 
 import logging as logging_base
+import os
 import sys
 
 from taskflow.listeners import base
@@ -148,7 +149,7 @@ class DynamicLoggingListener(base.Listener):
             # exc_info that can be used but we *should* have a string
             # version that we can use instead...
             exc_info = None
-            exc_details = "\n%s" % fail.pformat(traceback=True)
+            exc_details = "%s%s" % (os.linesep, fail.pformat(traceback=True))
         return (exc_info, exc_details)
 
     def _flow_receiver(self, state, details):

taskflow/types/failure.py

@@ -15,6 +15,7 @@
 #    under the License.
 
 import copy
+import os
 import sys
 import traceback
 
@@ -280,10 +281,13 @@ class Failure(object):
             else:
                 traceback_str = None
             if traceback_str:
-                buf.write('\nTraceback (most recent call last):\n')
+                buf.write(os.linesep)
+                buf.write('Traceback (most recent call last):')
+                buf.write(os.linesep)
                 buf.write(traceback_str)
             else:
-                buf.write('\nTraceback not available.')
+                buf.write(os.linesep)
+                buf.write('Traceback not available.')
         return buf.getvalue()
 
     def __iter__(self):

taskflow/types/graph.py

@@ -15,6 +15,7 @@
 #    under the License.
 
 import collections
+import os
 
 import networkx as nx
 import six
@@ -78,7 +79,7 @@ class DiGraph(nx.DiGraph):
                 buf.write(" --> %s" % (cycle[i]))
             buf.write(" --> %s" % (cycle[0]))
             lines.append("  %s" % buf.getvalue())
-        return "\n".join(lines)
+        return os.linesep.join(lines)
 
     def export_to_dot(self):
         """Exports the graph to a dot format (requires pydot library)."""

taskflow/types/table.py

@@ -15,6 +15,7 @@
 #    under the License.
 
 import itertools
+import os
 
 import six
 
@@ -39,6 +40,7 @@ class PleasantTable(object):
     COLUMN_SEPARATOR_CHAR = '|'
     HEADER_FOOTER_JOINING_CHAR = '+'
     HEADER_FOOTER_CHAR = '-'
+    LINE_SEP = os.linesep
 
     @staticmethod
     def _center_text(text, max_len, fill=' '):
@@ -87,7 +89,7 @@ class PleasantTable(object):
         # Build the main header.
         content_buf = six.StringIO()
         content_buf.write(header_footer_buf.getvalue())
-        content_buf.write("\n")
+        content_buf.write(self.LINE_SEP)
         content_buf.write(self.COLUMN_STARTING_CHAR)
         for i, header in enumerate(headers):
             if i + 1 == column_count:
@@ -99,12 +101,12 @@ class PleasantTable(object):
             else:
                 content_buf.write(headers[i])
                 content_buf.write(self.COLUMN_SEPARATOR_CHAR)
-        content_buf.write("\n")
+        content_buf.write(self.LINE_SEP)
         content_buf.write(header_footer_buf.getvalue())
         # Build the main content.
         row_count = len(self._rows)
         if row_count:
-            content_buf.write("\n")
+            content_buf.write(self.LINE_SEP)
             for i, row in enumerate(self._rows):
                 pieces = []
                 for j, column in enumerate(row):
@@ -122,7 +124,7 @@ class PleasantTable(object):
                         content_buf.write(self.COLUMN_STARTING_CHAR)
                         content_buf.write(blob)
                 if i + 1 != row_count:
-                    content_buf.write("\n")
+                    content_buf.write(self.LINE_SEP)
-            content_buf.write("\n")
+            content_buf.write(self.LINE_SEP)
             content_buf.write(header_footer_buf.getvalue())
         return content_buf.getvalue()

taskflow/types/tree.py

@@ -16,6 +16,8 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+import os
+
 import six
 
 
@@ -148,7 +150,7 @@ class Node(object):
         for i, line in enumerate(_inner_pformat(self, 0)):
             accumulator.write(line)
             if i < expected_lines:
-                accumulator.write('\n')
+                accumulator.write(os.linesep)
         return accumulator.getvalue()
 
     def child_count(self, only_direct=True):

taskflow/utils/misc.py

@@ -142,6 +142,11 @@ def clamp(value, minimum, maximum, on_clamped=None):
     return value
 
 
+def fix_newlines(text, replacement=os.linesep):
+    """Fixes text that *may* end with wrong nl by replacing with right nl."""
+    return replacement.join(text.splitlines())
+
+
 def binary_encode(text, encoding='utf-8'):
     """Converts a string of into a binary type using given encoding.
 

taskflow/utils/persistence_utils.py

@@ -15,6 +15,7 @@
 #    under the License.
 
 import contextlib
+import os
 
 from oslo.utils import timeutils
 from oslo.utils import uuidutils
@@ -139,7 +140,7 @@ def pformat_atom_detail(atom_detail, indent=0):
     lines.append("%s- failure = %s" % (" " * (indent + 1),
                                        bool(atom_detail.failure)))
     lines.extend(_format_meta(atom_detail.meta, indent=indent + 1))
-    return "\n".join(lines)
+    return os.linesep.join(lines)
 
 
 def pformat_flow_detail(flow_detail, indent=0):
@@ -149,7 +150,7 @@ def pformat_flow_detail(flow_detail, indent=0):
     lines.extend(_format_meta(flow_detail.meta, indent=indent + 1))
     for task_detail in flow_detail:
         lines.append(pformat_atom_detail(task_detail, indent=indent + 1))
-    return "\n".join(lines)
+    return os.linesep.join(lines)
 
 
 def pformat(book, indent=0):
@@ -167,4 +168,4 @@ def pformat(book, indent=0):
                         timeutils.isotime(book.updated_at)))
     for flow_detail in book:
         lines.append(pformat_flow_detail(flow_detail, indent=indent + 1))
-    return "\n".join(lines)
+    return os.linesep.join(lines)