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).

1 files changed, 50 insertions, 0 deletions

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.")