Re: [KVM-AUTOTEST PATCH] kvm_runtest_2.py: use pickle instead of shelve when loading/saving env

[Lucas Meneghel Rodrigues <lmr@redhat.com>]

On Sun, 2009-05-24 at 18:46 +0300, Michael Goldish wrote:
> pickle allows more control over the load/save process. Specifically, it enables
> us to dump the contents of an object to disk without having to unpickle it.
> shelve, which uses pickle, seems to pickle and unpickle every time sync() is
> called. This is bad for classes that need to be unpickled only once per test
> (such a class will be introduced in a future patch).

Looks good to me.

> Signed-off-by: Michael Goldish <mgoldish@redhat.com>
> ---
>  client/tests/kvm_runtest_2/kvm_runtest_2.py |   29 ++++++++++++++++++++------
>  1 files changed, 22 insertions(+), 7 deletions(-)
> 
> diff --git a/client/tests/kvm_runtest_2/kvm_runtest_2.py b/client/tests/kvm_runtest_2/kvm_runtest_2.py
> index a69951b..5f7f6ad 100644
> --- a/client/tests/kvm_runtest_2/kvm_runtest_2.py
> +++ b/client/tests/kvm_runtest_2/kvm_runtest_2.py
> @@ -3,9 +3,9 @@
>  import sys
>  import os
>  import time
> -import shelve
>  import random
>  import resource
> +import cPickle
>  
>  from autotest_lib.client.bin import test
>  from autotest_lib.client.common_lib import error
> @@ -18,6 +18,22 @@ class test_routine:
>          self.routine = None
>  
> 
> +def dump_env(obj, filename):
> +    file = open(filename, "w")
> +    cPickle.dump(obj, file)
> +    file.close()
> +
> +
> +def load_env(filename, default=None):
> +    try:
> +        file = open(filename, "r")
> +    except:
> +        return default
> +    obj = cPickle.load(file)
> +    file.close()
> +    return obj
> +
> +
>  class kvm_runtest_2(test.test):
>      version = 1
>  
> @@ -65,7 +81,7 @@ class kvm_runtest_2(test.test):
>  
>          # Open the environment file
>          env_filename = os.path.join(self.bindir, params.get("env", "env"))
> -        env = shelve.open(env_filename, writeback=True)
> +        env = load_env(env_filename, {})
>          kvm_log.debug("Contents of environment: %s" % str(env))
>  
>          try:
> @@ -87,24 +103,23 @@ class kvm_runtest_2(test.test):
>  
>                  # Preprocess
>                  kvm_preprocessing.preprocess(self, params, env)
> -                env.sync()
> +                dump_env(env, env_filename)
>                  # Run the test function
>                  routine_obj.routine(self, params, env)
> -                env.sync()
> +                dump_env(env, env_filename)
>  
>              except Exception, e:
>                  kvm_log.error("Test failed: %s" % e)
>                  kvm_log.debug("Postprocessing on error...")
>                  kvm_preprocessing.postprocess_on_error(self, params, env)
> -                env.sync()
> +                dump_env(env, env_filename)
>                  raise
>  
>          finally:
>              # Postprocess
>              kvm_preprocessing.postprocess(self, params, env)
>              kvm_log.debug("Contents of environment: %s" % str(env))
> -            env.sync()
> -            env.close()
> +            dump_env(env, env_filename)
>  
>      def postprocess(self):
>          pass
-- 
Lucas Meneghel Rodrigues
Software Engineer (QE)
Red Hat - Emerging Technologies