Add logfile kwarg to staging area runcmd

We use tee to write the output to a file as well as to stdout.
Using Popen it should be straight forward to send the output to a pipe and
then read that pipe and write to wherever.
At the moment morph uses cliapp's runcmd rather than Popen. cliapp's runcmd
is a blocking call, so we're not able to read from the pipe until the
command has completed, which prevents real time logging to a number of files.
One solution to this problem might be to spawn a thread which opens a pipe
to the command being executed, the thread then reads from the pipe and writes
to our collection of logfiles.

1 files changed, 8 insertions, 1 deletions

diff --git a/morphlib/stagingarea.py b/morphlib/stagingarea.py
index 61f9e660..124edabf 100644
--- a/morphlib/stagingarea.py
+++ b/morphlib/stagingarea.py
@@ -309,7 +309,14 @@ class StagingArea(object):
         real_argv += argv
 
         try:
-            return self._app.runcmd(real_argv, **kwargs)
+            if 'logfile' in kwargs and kwargs['logfile'] != None:
+                logfile = kwargs['logfile']
+                del kwargs['logfile']
+
+                teecmd = ['tee', '-a', logfile]
+                return self._app.runcmd(real_argv, teecmd, **kwargs)
+            else:
+                return self._app.runcmd(real_argv, **kwargs)
         except cliapp.AppException as e:
             raise cliapp.AppException('In staging area %s: running '
                                       'command \'%s\' failed.' %