Interceptors and thread-safety

[Shahak Nagiel <sn...@yahoo.com>]

The "Writing Interceptors" guide pretty clearly states that "Interceptors are shared between requests and must be thread-safe."   However, there are some Interceptors--such as execAndWait and roles--which accept parameters (e.g. "delay" and "allowedRoles") and which, ostensibly at least--use simple setter methods to apply these to instance variables.  So, how can these be thread-safe if new Interceptors aren't being instantiated for every request?

Thanks in advance.

Re: Interceptors and thread-safety

[Laurie Harper <la...@holoweb.net>]

Dave Newton wrote:
> --- Laurie Harper <la...@holoweb.net> wrote:
>> Shahak Nagiel wrote:
>>> So, how can these [interceptors] be thread-safe if 
>>> new Interceptors aren't being instantiated for
> every
>>> request?
>> Because the parameters don't come from (or vary
>> with) the request. 
> 
> Just to add on/clarify a little bit, this also implies
> that if you configure an interceptor for a specific
> action that an instance is created for that action,
> yes?

I don't know the answer to that, but I would expect it to work that 
way... I would guess there will be one interceptor instance for each 
interceptor config.

L.


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Re: Interceptors and thread-safety

[Dave Newton <ne...@yahoo.com>]

--- Laurie Harper <la...@holoweb.net> wrote:
> Shahak Nagiel wrote:
>> So, how can these [interceptors] be thread-safe if 
>> new Interceptors aren't being instantiated for
every
>> request?
> Because the parameters don't come from (or vary
> with) the request. 

Just to add on/clarify a little bit, this also implies
that if you configure an interceptor for a specific
action that an instance is created for that action,
yes?

Dave


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Re: Interceptors and thread-safety

[Laurie Harper <la...@holoweb.net>]

Shahak Nagiel wrote:
> The "Writing Interceptors" guide pretty clearly states that "Interceptors are shared between requests and must be thread-safe."   However, there are some Interceptors--such as execAndWait and roles--which accept parameters (e.g. "delay" and "allowedRoles") and which, ostensibly at least--use simple setter methods to apply these to instance variables.  So, how can these be thread-safe if new Interceptors aren't being instantiated for every request?

Because the parameters don't come from (or vary with) the request. 
Interceptor parameters are passed in once, when the interceptor is 
instantiated. That same instance is then applied to each request for 
which it's configured.

L.


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