Use a fake serial module that will allow tests to contine

Instead of aborting all serial using tests instead just
create a serial module in cloudinit that will create a fake
and broken serial class when pyserial is not actually installed.

This allows for using the datasource and tests that exist in
a more functional and tested manner (even when pyserial is not
found).

3 files changed, 53 insertions, 4 deletions

diff --git a/cloudinit/cs_utils.py b/cloudinit/cs_utils.py
index 83ac1a0e..412431f2 100644
--- a/cloudinit/cs_utils.py
+++ b/cloudinit/cs_utils.py
@@ -33,7 +33,8 @@ API Docs: http://cloudsigma-docs.readthedocs.org/en/latest/server_context.html
 import json
 import platform
 
-import serial
+from cloudinit import serial
+
 
 # these high timeouts are necessary as read may read a lot of data.
 READ_TIMEOUT = 60
diff --git a/cloudinit/serial.py b/cloudinit/serial.py
new file mode 100644
index 00000000..af45c13e
--- /dev/null
+++ b/cloudinit/serial.py
@@ -0,0 +1,50 @@
+# vi: ts=4 expandtab
+#
+#    This program is free software: you can redistribute it and/or modify
+#    it under the terms of the GNU General Public License version 3, as
+#    published by the Free Software Foundation.
+#
+#    This program is distributed in the hope that it will be useful,
+#    but WITHOUT ANY WARRANTY; without even the implied warranty of
+#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#    GNU General Public License for more details.
+#
+#    You should have received a copy of the GNU General Public License
+#    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+
+from __future__ import absolute_import
+
+try:
+    from serial import Serial
+except ImportError:
+    # For older versions of python (ie 2.6) pyserial may not exist and/or
+    # work and/or be installed, so make a dummy/fake serial that blows up
+    # when used...
+    class Serial(object):
+        def __init__(self, *args, **kwargs):
+            pass
+
+        @staticmethod
+        def isOpen():
+            return False
+
+        @staticmethod
+        def write(data):
+            raise IOError("Unable to perform serial `write` operation,"
+                          " pyserial not installed.")
+
+        @staticmethod
+        def readline():
+            raise IOError("Unable to perform serial `readline` operation,"
+                          " pyserial not installed.")
+
+        @staticmethod
+        def flush():
+            raise IOError("Unable to perform serial `flush` operation,"
+                          " pyserial not installed.")
+
+        @staticmethod
+        def read(size=1):
+            raise IOError("Unable to perform serial `read` operation,"
+                          " pyserial not installed.")
diff --git a/cloudinit/sources/DataSourceSmartOS.py b/cloudinit/sources/DataSourceSmartOS.py
index 6cbd8dfa..c7641eb3 100644
--- a/cloudinit/sources/DataSourceSmartOS.py
+++ b/cloudinit/sources/DataSourceSmartOS.py
@@ -40,13 +40,11 @@ import re
 import socket
 import stat
 
-import serial
-
 from cloudinit import log as logging
+from cloudinit import serial
 from cloudinit import sources
 from cloudinit import util
 
-
 LOG = logging.getLogger(__name__)
 
 SMARTOS_ATTRIB_MAP = {