Google Cloud Storage support using gcsfs

Author: bnaul

ci/check_imports.py

@@ -5,6 +5,7 @@
 
 blacklist = {
     'bs4',
+    'gcsfs',
     'html5lib',
     'ipython',
     'jinja2'

ci/requirements-optional-pip.txt

@@ -26,4 +26,4 @@ sqlalchemy
 xarray
 xlrd
 xlsxwriter
-xlwt
+xlwt

doc/source/install.rst

@@ -276,6 +276,7 @@ Optional Dependencies
 * `Jinja2 <http://jinja.pocoo.org/>`__: Template engine for conditional HTML formatting.
 * `s3fs <http://s3fs.readthedocs.io/>`__: necessary for Amazon S3 access (s3fs >= 0.0.7).
 * `blosc <https://pypi.org/project/blosc>`__: for msgpack compression using ``blosc``
+* `gcsfs <http://gcsfs.readthedocs.io/>`__: necessary for Google Cloud Storage access (gcsfs >= 0.1.0).
 * One of
   `qtpy  <https://github.com/spyder-ide/qtpy>`__ (requires PyQt or PySide),
   `PyQt5 <https://www.riverbankcomputing.com/software/pyqt/download5>`__,

pandas/io/common.py

@@ -88,7 +88,7 @@ def _is_url(url):
     """
     try:
         return parse_url(url).scheme in _VALID_URLS
-    except:
+    except Exception:
         return False
 
 
@@ -165,7 +165,15 @@ def is_s3_url(url):
     """Check for an s3, s3n, or s3a url"""
     try:
         return parse_url(url).scheme in ['s3', 's3n', 's3a']
-    except:  # noqa
+    except Exception:
+        return False
+
+
+def is_gcs_url(url):
+    """Check for a gcs url"""
+    try:
+        return parse_url(url).scheme in ['gcs', 'gs']
+    except Exception:
         return False
 
 
@@ -208,6 +216,13 @@ def get_filepath_or_buffer(filepath_or_buffer, encoding=None,
                                          compression=compression,
                                          mode=mode)
 
+    if is_gcs_url(filepath_or_buffer):
+        from pandas.io import gcs
+        return gcs.get_filepath_or_buffer(filepath_or_buffer,
+                                          encoding=encoding,
+                                          compression=compression,
+                                          mode=mode)
+
     if isinstance(filepath_or_buffer, (compat.string_types,
                                        compat.binary_type,
                                        mmap.mmap)):

pandas/io/excel.py

@@ -46,7 +46,7 @@
 io : string, path object (pathlib.Path or py._path.local.LocalPath),
     file-like object, pandas ExcelFile, or xlrd workbook.
     The string could be a URL. Valid URL schemes include http, ftp, s3,
-    and file. For file URLs, a host is expected. For instance, a local
+    gcs, and file. For file URLs, a host is expected. For instance, a local
     file could be file://localhost/path/to/workbook.xlsx
 sheet_name : string, int, mixed list of strings/ints, or None, default 0
 

pandas/io/gcs.py

@@ -0,0 +1,16 @@
+""" GCS support for remote file interactivity """
+try:
+    import gcsfs
+except ImportError:
+    raise ImportError("The gcsfs library is required to handle GCS files")
+
+
+def get_filepath_or_buffer(filepath_or_buffer, encoding=None,
+                           compression=None, mode=None):
+
+    if mode is None:
+        mode = 'rb'
+
+    fs = gcsfs.GCSFileSystem()
+    filepath_or_buffer = fs.open(filepath_or_buffer, mode)
+    return filepath_or_buffer, None, compression, True

pandas/io/json/json.py

@@ -231,9 +231,9 @@ def read_json(path_or_buf=None, orient=None, typ='frame', dtype=True,
     Parameters
     ----------
     path_or_buf : a valid JSON string or file-like, default: None
-        The string could be a URL. Valid URL schemes include http, ftp, s3, and
-        file. For file URLs, a host is expected. For instance, a local file
-        could be ``file://localhost/path/to/table.json``
+        The string could be a URL. Valid URL schemes include http, ftp, s3,
+        gcs, and file. For file URLs, a host is expected. For instance, a local
+        file could be ``file://localhost/path/to/table.json``
 
     orient : string,
         Indication of expected JSON string format.

pandas/tests/io/test_gcs.py

@@ -0,0 +1,26 @@
+from pandas import DataFrame, read_csv
+from pandas.compat import BytesIO
+from pandas.io.common import is_gcs_url
+
+
+class TestGCSURL(object):
+
+    def test_is_gcs_url(self):
+        assert is_gcs_url("gcs://pandas/somethingelse.com")
+        assert is_gcs_url("gs://pandas/somethingelse.com")
+        assert not is_gcs_url("s3://pandas/somethingelse.com")
+
+    def test_read_csv_gcs(self):
+        try:
+            from unittest.mock import patch
+        except ImportError:
+            from mock import patch
+
+        with patch('gcsfs.GCSFileSystem') as MockFileSystem:
+            instance = MockFileSystem.return_value
+            instance.open.return_value = BytesIO(b'a,b\n1,2\n3,4')
+            df = read_csv('gs://test/test.csv')
+
+        assert isinstance(df, DataFrame)
+        assert len(df == 2)
+        assert all(df.columns == ['a', 'b'])

pandas/util/_print_versions.py

@@ -96,6 +96,7 @@ def show_versions(as_json=False):
         ("fastparquet", lambda mod: mod.__version__),
         ("pandas_gbq", lambda mod: mod.__version__),
         ("pandas_datareader", lambda mod: mod.__version__),
+        ("gcsfs", lambda mod: mod.__version__),
     ]
 
     deps_blob = list()