Re: [Squid Web Proxy Wiki] Update of "Features/AddonHelpers" by ChristosTsantilas

On 09/20/2012 04:54 AM, Tsantilas Christos wrote:
> On 09/20/2012 09:40 AM, Amos Jeffries wrote:
>> On 20/09/2012 9:40 a.m., wiki_at_wiki.squid-cache.org wrote:
>>
>>> + === SSL server certificate validator ===
>>> +
>>> + ## start sslcrtvd protocol
>>> + This interface is similar to the SSL certificate generation interface.
>>> +
>>> + Input ''line'' received from Squid:
>>> + {{{
>>> + request size [body]
>>> + }}}
>>> +
>>
>> Please make sure this interface is supporting concurrency. The helper
>> core routines do.
>
> The helperSubmit method used to submit request so looking in the code
> looks that both SSL certificate generation and validation helper
> interfaces should support concurrency.
> But I did not check it. Todo...

Amos, please correct me if I am wrong, but I think we need to add some
kind of request ID field to the validation request and validation
response messages for future helpers to be able to support concurrent
requests. If the existing trunk code does that automagically, great. If
not, let's add a new field and make sure that the sample helper returns
it in the response (so that Squid can match requests with responses).

The sample helper does not have to support concurrent requests, of course.

>> What about tag= to tag the transaction with a meta low/group tag?
>> What about passing an existing transaction tag to the helper?
>> What about log= ? (ie a loggable compaction of all those errors)
>
> At this time we do not need to tag or log transactions.

If other helpers support tags, let's add that support (in both
directions). Otherwise, this can be left as a future feature or even
ignored if a better feature is available (see below).

As for "log", a much better mechanism would be meta headers, IMO: They
support more than one named entry, they can be matched using ACLs, they
can be passed to adaptation services, and they can be logged, all using
existing code (patch posted to squid-dev earlier). I suggest that this
is revisited as a separate project where we can discuss the right helper
message syntax to send and receive meta headers.

Thank you,

Alex.
Received on Thu Sep 20 2012 - 18:13:15 MDT