[Seaside] a <sameAs:> DNU from : ZnMessage>>isConnectionClose

[Sven Van Caekenberghe]

Hi,

I would still like to understand how you get in this situation.

You could try the following modification:

ZnMultiValueDictionary>>#at: key add: value
  "Store value under key. If key already exists, store multiple values as Array"
	
  | existingValue newValue |
  existingValue := self at: key ifAbsent: [ nil ].
  newValue := existingValue isNil
    ifTrue: [ value ] 
    ifFalse: [
      existingValue isArray 
        ifTrue: [ 
          (existingValue includes: value) ifTrue: [ ^ value ].
          existingValue copyWith: value ]
        ifFalse: [
          existingValue = value ifTrue: [ ^ value ].
          Array with: existingValue with: value ] ].
  ^ self at: key put: newValue 

This changes one method in a data structure underlying ZnHeaders to prevent it from accepting double entries.

This way, the following expression,

  ZnMultiValueDictionary new at: 'Connection' add: 'close'; at: 'Connection' add: 'close'; yourself.

will result in just one simple association being stored.

Please let me know if this helps.

Sven

> On 27 Apr 2018, at 14:06, lb <liangbing64 at 126.com> wrote:
> 
> Hi Sven
> It came again.
> Array(Object)>>doesNotUnderstand: #sameAs:
> ZnRequest(ZnMessage)>>isConnectionClose
> ZnRequest>>wantsConnectionClose
> ZnResponse>>setConnectionCloseFor:
> ZnManagingMultiThreadedServer(ZnMultiThreadedServer)>>augmentResponse:forRequest:
> ZnManagingMultiThreadedServer(ZnMultiThreadedServer)>>executeOneRequestResponseOn:
> [ [ self executeOneRequestResponseOn: stream ] whileFalse ] in ZnManagingMultiThreadedServer(ZnMultiThreadedServer)>>executeRequestResponseLoopOn:
> [ activeProcess psValueAt: index put: anObject.
> aBlock value ] in ZnCurrentServer(DynamicVariable)>>value:during:
> BlockClosure>>ensure:
> ZnCurrentServer(DynamicVariable)>>value:during:
> ZnCurrentServer class(DynamicVariable class)>>value:during:
> ZnManagingMultiThreadedServer(ZnMultiThreadedServer)>>executeRequestResponseLoopOn:
> [ self executeRequestResponseLoopOn: stream ] in [ [ self executeRequestResponseLoopOn: stream ]
>  ensure: [ self logConnectionClosed: stream.
>   self closeSocketStream: stream ] ] in [ [ [ self executeRequestResponseLoopOn: stream ]
>  ensure: [ self logConnectionClosed: stream.
>   self closeSocketStream: stream ] ]
>  ifCurtailed: [ socket destroy ] ] in ZnManagingMultiThreadedServer(ZnMultiThreadedServer)>>serveConnectionsOn:
> BlockClosure>>ensure:
> [ [ self executeRequestResponseLoopOn: stream ]
>  ensure: [ self logConnectionClosed: stream.
>   self closeSocketStream: stream ] ] in [ [ [ self executeRequestResponseLoopOn: stream ]
>  ensure: [ self logConnectionClosed: stream.
>   self closeSocketStream: stream ] ]
>  ifCurtailed: [ socket destroy ] ] in ZnManagingMultiThreadedServer(ZnMultiThreadedServer)>>serveConnectionsOn:
> BlockClosure>>ifCurtailed:
> [ [ [ self executeRequestResponseLoopOn: stream ]
>  ensure: [ self logConnectionClosed: stream.
>   self closeSocketStream: stream ] ]
>  ifCurtailed: [ socket destroy ] ] in ZnManagingMultiThreadedServer(ZnMultiThreadedServer)>>serveConnectionsOn:
> [ self value.
> Processor terminateActive ] in BlockClosure>>newProcess
> 
> 
> 
> At 2018-04-12 21:47:24, "lb" <liangbing64 at 126.com> wrote:
> Hi, Sven,
> Thank you very much,
> But I am not familiar with HTTP. I recover to original code now.
> when that occurs next time, I will copy the error stack here.
> 
> 
> Best regards
> 
> Liang
> 
> 
> 
> At 2018-04-12 20:21:07, "Sven Van Caekenberghe" <sven at stfx.eu
> > wrote:
> >Hi Liang,
> >
> >Headers in HTTP (as represented/implemented by the ZnHeaders object in Pharo) can be multi-valued. That is, a certain header name (key) can occur more than once. That creates a multi-valued situation. For example, there can be multiple cookies being set. But almost always, there is only one header with a unique name.
> >
> >What you see must be the result of the 'Connection:close' header line being present twice. I would like to understand how that can happen. Do you have any idea ?
> >
> >I am also not sure (I should check) what the spec says.
> >
> >What is special here is that although the header line occurs twice, it has the same/identical value.
> >
> >In any case, it is the first time I hear about this situation.
> >
> >Sven 
> >
> >> On 12 Apr 2018, at 11:30, lb <
> liangbing64 at 126.com
> > wrote:
> >> 
> >> Hi,
> >> my website always receives a sameAs: DNU from :
> >> ZnMessage>>isConnectionClose
> >>  | value |
> >>  value := self headers at: 'Connection' ifAbsent: [ ^ false ].
> >>  ^ value sameAs: 'close'
> >> 
> >> value is an Array like #('close' 'close').
> >> 
> >> I fix like this to avoid receiving DNU message.
> >> isConnectionClose
> >>  | value |
> >>  value := self headers at: 'Connection' ifAbsent: [ ^ false ].
> >>  value isArray ifTrue: [^ (value at: 1) sameAs: 'close'].
> >>  value isString ifTrue: [^ value sameAs: 'close'].
> >>  ^false
> >> I can not confirm that fix is correct.
> >> Liang
> >> _______________________________________________
> >> seaside mailing list
> >> 
> seaside at lists.squeakfoundation.org
> 
> >> http://lists.squeakfoundation.org/cgi-bin/mailman/listinfo/seaside
> >
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