oeqa: add proper handling for command errors where needed

For use outside of tests themselves, we want a better error than
AssertionError, so create one and allow us to request it when calling
runCmd(). This enables us to avoid tracebacks during master image
operations if the power control command fails.

(From OE-Core rev: 89868383685091b0d3723fb8f29590f3f6610078)

Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/lib/oeqa/controllers/masterimage.py

@@ -20,6 +20,7 @@ import subprocess
 import oeqa.targetcontrol
 import oeqa.utils.sshcontrol as sshcontrol
 import oeqa.utils.commands as commands
+from oeqa.utils import CommandError
 
 from abc import ABCMeta, abstractmethod
 
@@ -94,7 +95,10 @@ class MasterImageHardwareTarget(oeqa.targetcontrol.BaseTarget):
     def power_ctl(self, msg):
         if self.powercontrol_cmd:
             cmd = "%s %s" % (self.powercontrol_cmd, msg)
-            commands.runCmd(cmd, preexec_fn=os.setsid, env=self.origenv)
+            try:
+                commands.runCmd(cmd, assert_error=False, preexec_fn=os.setsid, env=self.origenv)
+            except CommandError as e:
+                bb.fatal(str(e))
 
     def power_cycle(self, conn):
         if self.powercontrol_cmd:

meta/lib/oeqa/utils/__init__.py

@@ -1,3 +1,15 @@
 # Enable other layers to have modules in the same named directory
 from pkgutil import extend_path
 __path__ = extend_path(__path__, __name__)
+
+
+# Borrowed from CalledProcessError
+
+class CommandError(Exception):
+    def __init__(self, retcode, cmd, output = None):
+        self.retcode = retcode
+        self.cmd = cmd
+        self.output = output
+    def __str__(self):
+        return "Command '%s' returned non-zero exit status %d with output: %s" % (self.cmd, self.retcode, self.output)
+

meta/lib/oeqa/utils/commands.py

@@ -1,4 +1,4 @@
-# Copyright (c) 2013 Intel Corporation
+# Copyright (c) 2013-2014 Intel Corporation
 #
 # Released under the MIT license (see COPYING.MIT)
 
@@ -14,6 +14,7 @@ import signal
 import subprocess
 import threading
 import logging
+from oeqa.utils import CommandError
 
 class Command(object):
     def __init__(self, command, bg=False, timeout=None, data=None, **options):
@@ -84,8 +85,8 @@ class Command(object):
 class Result(object):
     pass
 
-def runCmd(command, ignore_status=False, timeout=None, **options):
 
+def runCmd(command, ignore_status=False, timeout=None, assert_error=True, **options):
     result = Result()
 
     cmd = Command(command, timeout=timeout, **options)
@@ -97,7 +98,10 @@ def runCmd(command, ignore_status=False, timeout=None, **options):
     result.pid = cmd.process.pid
 
     if result.status and not ignore_status:
-        raise AssertionError("Command '%s' returned non-zero exit status %d:\n%s" % (command, result.status, result.output))
+        if assert_error:
+            raise AssertionError("Command '%s' returned non-zero exit status %d:\n%s" % (command, result.status, result.output))
+        else:
+            raise CommandError(result.status, command, result.output)
 
     return result