Refactor a large part of the networking code.

Splits off distro specific code into specific files so that
other kinds of networking configuration can be written by the
various distro(s) that cloud-init supports.

It also isolates some of the cloudinit.net code so that it can
be more easily used on its own (and incorporated into other
projects such as curtin).

During this process it adds tests so that the net process can
be tested (to some level) so that the format conversion processes
can be tested going forward.

1 files changed, 13 insertions, 3 deletions

diff --git a/cloudinit/util.py b/cloudinit/util.py
index d6b80dbe..8873264d 100644
--- a/cloudinit/util.py
+++ b/cloudinit/util.py
@@ -171,7 +171,8 @@ class ProcessExecutionError(IOError):
 
     def __init__(self, stdout=None, stderr=None,
                  exit_code=None, cmd=None,
-                 description=None, reason=None):
+                 description=None, reason=None,
+                 errno=None):
         if not cmd:
             self.cmd = '-'
         else:
@@ -202,6 +203,7 @@ class ProcessExecutionError(IOError):
         else:
             self.reason = '-'
 
+        self.errno = errno
         message = self.MESSAGE_TMPL % {
             'description': self.description,
             'cmd': self.cmd,
@@ -1157,7 +1159,14 @@ def find_devs_with(criteria=None, oformat='device',
         options.append(path)
     cmd = blk_id_cmd + options
     # See man blkid for why 2 is added
-    (out, _err) = subp(cmd, rcs=[0, 2])
+    try:
+        (out, _err) = subp(cmd, rcs=[0, 2])
+    except ProcessExecutionError as e:
+        if e.errno == errno.ENOENT:
+            # blkid not found...
+            out = ""
+        else:
+            raise
     entries = []
     for line in out.splitlines():
         line = line.strip()
@@ -1706,7 +1715,8 @@ def subp(args, data=None, rcs=None, env=None, capture=True, shell=False,
         sp = subprocess.Popen(args, **kws)
         (out, err) = sp.communicate(data)
     except OSError as e:
-        raise ProcessExecutionError(cmd=args, reason=e)
+        raise ProcessExecutionError(cmd=args, reason=e,
+                                    errno=e.errno)
     rc = sp.returncode
     if rc not in rcs:
         raise ProcessExecutionError(stdout=out, stderr=err,