COMPAT: boto import issues

pandas/io/common.py

@@ -104,85 +104,6 @@ def __next__(self):
     BaseIterator.next = lambda self: self.__next__()
 
 
-try:
-    from boto.s3 import key
-
-    class BotoFileLikeReader(key.Key):
-        """boto Key modified to be more file-like
-
-        This modification of the boto Key will read through a supplied
-        S3 key once, then stop. The unmodified boto Key object will repeatedly
-        cycle through a file in S3: after reaching the end of the file,
-        boto will close the file. Then the next call to `read` or `next` will
-        re-open the file and start reading from the beginning.
-
-        Also adds a `readline` function which will split the returned
-        values by the `\n` character.
-        """
-
-        def __init__(self, *args, **kwargs):
-            encoding = kwargs.pop("encoding", None)  # Python 2 compat
-            super(BotoFileLikeReader, self).__init__(*args, **kwargs)
-            # Add a flag to mark the end of the read.
-            self.finished_read = False
-            self.buffer = ""
-            self.lines = []
-            if encoding is None and compat.PY3:
-                encoding = "utf-8"
-            self.encoding = encoding
-            self.lines = []
-
-        def next(self):
-            return self.readline()
-
-        __next__ = next
-
-        def read(self, *args, **kwargs):
-            if self.finished_read:
-                return b'' if compat.PY3 else ''
-            return super(BotoFileLikeReader, self).read(*args, **kwargs)
-
-        def close(self, *args, **kwargs):
-            self.finished_read = True
-            return super(BotoFileLikeReader, self).close(*args, **kwargs)
-
-        def seekable(self):
-            """Needed for reading by bz2"""
-            return False
-
-        def readline(self):
-            """Split the contents of the Key by '\n' characters."""
-            if self.lines:
-                retval = self.lines[0]
-                self.lines = self.lines[1:]
-                return retval
-            if self.finished_read:
-                if self.buffer:
-                    retval, self.buffer = self.buffer, ""
-                    return retval
-                else:
-                    raise StopIteration
-
-            if self.encoding:
-                self.buffer = "{}{}".format(
-                    self.buffer, self.read(8192).decode(self.encoding))
-            else:
-                self.buffer = "{}{}".format(self.buffer, self.read(8192))
-
-            split_buffer = self.buffer.split("\n")
-            self.lines.extend(split_buffer[:-1])
-            self.buffer = split_buffer[-1]
-
-            return self.readline()
-except ImportError:
-    # boto is only needed for reading from S3.
-    pass
-except TypeError:
-    # boto/boto3 issues
-    # GH11915
-    pass
-
-
 def _is_url(url):
     """Check to see if a URL has a valid protocol.
 
@@ -319,32 +240,10 @@ def get_filepath_or_buffer(filepath_or_buffer, encoding=None,
         return tuple(to_return)
 
     if _is_s3_url(filepath_or_buffer):
-        try:
-            import boto
-        except:
-            raise ImportError("boto is required to handle s3 files")
-        # Assuming AWS_ACCESS_KEY_ID, AWS_SECRET_ACCESS_KEY and AWS_S3_HOST
-        # are environment variables
-        parsed_url = parse_url(filepath_or_buffer)
-        s3_host = os.environ.get('AWS_S3_HOST', 's3.amazonaws.com')
-
-        try:
-            conn = boto.connect_s3(host=s3_host)
-        except boto.exception.NoAuthHandlerFound:
-            conn = boto.connect_s3(host=s3_host, anon=True)
-
-        b = conn.get_bucket(parsed_url.netloc, validate=False)
-        if compat.PY2 and (compression == 'gzip' or
-                           (compression == 'infer' and
-                            filepath_or_buffer.endswith(".gz"))):
-            k = boto.s3.key.Key(b, parsed_url.path)
-            filepath_or_buffer = BytesIO(k.get_contents_as_string(
-                encoding=encoding))
-        else:
-            k = BotoFileLikeReader(b, parsed_url.path, encoding=encoding)
-            k.open('r')  # Expose read errors immediately
-            filepath_or_buffer = k
-        return filepath_or_buffer, None, compression
+        from pandas.io.s3 import get_filepath_or_buffer
+        return get_filepath_or_buffer(filepath_or_buffer,
+                                      encoding=encoding,
+                                      compression=compression)
 
     # It is a pathlib.Path/py.path.local or string
     filepath_or_buffer = _stringify_path(filepath_or_buffer)

pandas/io/s3.py

@@ -0,0 +1,112 @@
+""" s3 support for remote file interactivity """
+
+import os
+from pandas import compat
+from pandas.compat import BytesIO
+
+try:
+    import boto
+    from boto.s3 import key
+except:
+    raise ImportError("boto is required to handle s3 files")
+
+if compat.PY3:
+    from urllib.parse import urlparse as parse_url
+else:
+    from urlparse import urlparse as parse_url
+
+
+class BotoFileLikeReader(key.Key):
+    """boto Key modified to be more file-like
+
+    This modification of the boto Key will read through a supplied
+    S3 key once, then stop. The unmodified boto Key object will repeatedly
+    cycle through a file in S3: after reaching the end of the file,
+    boto will close the file. Then the next call to `read` or `next` will
+    re-open the file and start reading from the beginning.
+
+    Also adds a `readline` function which will split the returned
+    values by the `\n` character.
+    """
+
+    def __init__(self, *args, **kwargs):
+        encoding = kwargs.pop("encoding", None)  # Python 2 compat
+        super(BotoFileLikeReader, self).__init__(*args, **kwargs)
+        # Add a flag to mark the end of the read.
+        self.finished_read = False
+        self.buffer = ""
+        self.lines = []
+        if encoding is None and compat.PY3:
+            encoding = "utf-8"
+        self.encoding = encoding
+        self.lines = []
+
+    def next(self):
+        return self.readline()
+
+    __next__ = next
+
+    def read(self, *args, **kwargs):
+        if self.finished_read:
+            return b'' if compat.PY3 else ''
+        return super(BotoFileLikeReader, self).read(*args, **kwargs)
+
+    def close(self, *args, **kwargs):
+        self.finished_read = True
+        return super(BotoFileLikeReader, self).close(*args, **kwargs)
+
+    def seekable(self):
+        """Needed for reading by bz2"""
+        return False
+
+    def readline(self):
+        """Split the contents of the Key by '\n' characters."""
+        if self.lines:
+            retval = self.lines[0]
+            self.lines = self.lines[1:]
+            return retval
+        if self.finished_read:
+            if self.buffer:
+                retval, self.buffer = self.buffer, ""
+                return retval
+            else:
+                raise StopIteration
+
+        if self.encoding:
+            self.buffer = "{}{}".format(
+                self.buffer, self.read(8192).decode(self.encoding))
+        else:
+            self.buffer = "{}{}".format(self.buffer, self.read(8192))
+
+        split_buffer = self.buffer.split("\n")
+        self.lines.extend(split_buffer[:-1])
+        self.buffer = split_buffer[-1]
+
+        return self.readline()
+
+
+def get_filepath_or_buffer(filepath_or_buffer, encoding=None,
+                           compression=None):
+
+    # Assuming AWS_ACCESS_KEY_ID, AWS_SECRET_ACCESS_KEY and AWS_S3_HOST
+    # are environment variables
+    parsed_url = parse_url(filepath_or_buffer)
+    s3_host = os.environ.get('AWS_S3_HOST', 's3.amazonaws.com')
+
+    try:
+        conn = boto.connect_s3(host=s3_host)
+    except boto.exception.NoAuthHandlerFound:
+        conn = boto.connect_s3(host=s3_host, anon=True)
+
+    b = conn.get_bucket(parsed_url.netloc, validate=False)
+    if compat.PY2 and (compression == 'gzip' or
+                       (compression == 'infer' and
+                        filepath_or_buffer.endswith(".gz"))):
+        k = boto.s3.key.Key(b, parsed_url.path)
+        filepath_or_buffer = BytesIO(k.get_contents_as_string(
+            encoding=encoding))
+    else:
+        k = BotoFileLikeReader(b, parsed_url.path, encoding=encoding)
+        k.open('r')  # Expose read errors immediately
+        filepath_or_buffer = k
+    return filepath_or_buffer, None, compression

pandas/io/tests/test_data.py

@@ -472,9 +472,6 @@ def test_options_source_warning(self):
 
 
 class TestDataReader(tm.TestCase):
-    def test_is_s3_url(self):
-        from pandas.io.common import _is_s3_url
-        self.assertTrue(_is_s3_url("s3://pandas/somethingelse.com"))
 
     @network
     def test_read_yahoo(self):

pandas/io/tests/test_s3.py

@@ -0,0 +1,14 @@
+import nose
+from pandas.util import testing as tm
+
+from pandas.io.common import _is_s3_url
+
+
+class TestS3URL(tm.TestCase):
+    def test_is_s3_url(self):
+        self.assertTrue(_is_s3_url("s3://pandas/somethingelse.com"))
+        self.assertFalse(_is_s3_url("s4://pandas/somethingelse.com"))
+
+if __name__ == '__main__':
+    nose.runmodule(argv=[__file__, '-vvs', '-x', '--pdb', '--pdb-failure'],
+                   exit=False)