How to filter App Engine access logs for requests without a parameter

I want to introduce a new mandatory parameter to the API of my webservice I have deployed on App Engine. However, before I enable the server side check I want to check whether all the clients have been updated to send the parameter.

App Engine provides a GUI for开发者_开发百科 searching the access log. I want to use this to find all logs which don't contain the new parameter.

I know from How to "inverse match" with regex? that I should be able to use the regex "(?!paramname)" but this currently returns an error from App Engine:

Client Error

The request is invalid for an unspecified reason.

Is there another way for me to do this? I'm not interested in solutions which involve me downloading the logs.

EDIT: This has already been raised as a bug: http://code.google.com/p/googleappengine/issues/detail?id=1874

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I know you asked not for methods involving downloading logs, but since you could list all your logs and grep away the ones you don't want in your shell with just a single line using appcfg.py I still thought it would be worth noting.

So if you wanted to dump all your logs by browsers that are not Safari you could run:

$ appcfg.py request_logs --include_all --severity=0 /path/to/app - | grep -v "Safari"