Merge pull request #3859 from catleeball/fd-writer

Added print_to_fd to utils.py

2 files changed, 84 insertions, 2 deletions

diff --git a/boto/s3/key.py b/boto/s3/key.py
index 35f04c9f..f9260258 100644
--- a/boto/s3/key.py
+++ b/boto/s3/key.py
@@ -46,7 +46,7 @@ import boto.utils
 from boto.utils import compute_md5, compute_hash
 from boto.utils import find_matching_headers
 from boto.utils import merge_headers_by_name
-
+from boto.utils import print_to_fd
 
 class Key(object):
     """
@@ -1553,7 +1553,7 @@ class Key(object):
             cb(data_len, cb_size)
         try:
             for key_bytes in self:
-                print(key_bytes, file=fp, end='')
+                print_to_fd(six.ensure_binary(key_bytes), file=fp, end=b'')
                 data_len += len(key_bytes)
                 for alg in digesters:
                     digesters[alg].update(key_bytes)
diff --git a/boto/utils.py b/boto/utils.py
index 531a72d3..35637772 100644
--- a/boto/utils.py
+++ b/boto/utils.py
@@ -44,11 +44,13 @@ import time
 import logging.handlers
 import boto
 import boto.provider
+import collections
 import tempfile
 import random
 import smtplib
 import datetime
 import re
+import io
 import email.mime.multipart
 import email.mime.base
 import email.mime.text
@@ -57,6 +59,7 @@ import email.encoders
 import gzip
 import threading
 import locale
+import sys
 from boto.compat import six, StringIO, urllib, encodebytes
 
 from contextlib import contextmanager
@@ -1098,3 +1101,82 @@ def parse_host(hostname):
     else:
         return hostname.split(':', 1)[0]
 
+def print_to_fd(*objects, **kwargs):
+    """A Python 2/3 compatible analogue to the print function.
+
+    This function writes text to a file descriptor as the
+    builtin print function would, favoring utf-8 encoding.
+    Arguments and return values are the same as documented in
+    the Python 2 print function.
+    """
+    def _get_args(**kwargs):
+        """Validates keyword arguments that would be used in Print
+        Valid keyword arguments, mirroring print(), are 'sep',
+        'end', and 'file'. These must be of types string, string,
+        and file / file interface respectively.
+        Returns the above kwargs of the above types.
+        """
+        expected_keywords = collections.OrderedDict([
+            ('sep', ' '),
+            ('end', '\n'),
+            ('file', sys.stdout)])
+
+        for key, value in kwargs.items():
+            if key not in expected_keywords:
+                error_msg = (
+                    '{} is not a valid keyword argument. '
+                    'Please use one of: {}')
+                raise KeyError(
+                    error_msg.format(
+                        key,
+                        ' '.join(expected_keywords.keys())))
+            else:
+                expected_keywords[key] = value
+
+        return expected_keywords.values()
+
+    def _get_byte_strings(*objects):
+        """Gets a `bytes` string for each item in list of printable objects."""
+        byte_objects = []
+        for item in objects:
+            if not isinstance(item, (six.binary_type, six.text_type)):
+                # If the item wasn't bytes or unicode, its __str__ method
+                # should return one of those types.
+                item = str(item)
+
+            if isinstance(item, six.binary_type):
+                byte_objects.append(item)
+            else:
+                # The item should be unicode. If it's not, ensure_binary()
+                # will throw a TypeError.
+                byte_objects.append(six.ensure_binary(item))
+        return byte_objects
+
+    sep, end, file = _get_args(**kwargs)
+    sep = six.ensure_binary(sep)
+    end = six.ensure_binary(end)
+    data = _get_byte_strings(*objects)
+    data = sep.join(data)
+    data += end
+    write_to_fd(file, data)
+
+
+def write_to_fd(fd, data):
+    """Write given data to given file descriptor, doing any conversions needed"""
+    if six.PY2:
+        fd.write(data)
+        return
+    # PY3 logic:
+    if isinstance(data, bytes):
+        if ((hasattr(fd, 'mode') and 'b' in fd.mode) or
+                isinstance(fd, io.BytesIO)):
+            fd.write(data)
+        elif hasattr(fd, 'buffer'):
+            fd.buffer.write(data)
+        else:
+            fd.write(six.ensure_text(data))
+    elif 'b' in fd.mode:
+        fd.write(six.ensure_binary(data))
+    else:
+        fd.write(data)
+