What is a valid key?

Aaron Stone aaron at serendipity.cx
Thu Dec 20 19:25:00 UTC 2007

It's nice to have a text protocol for human interaction over the wire, but
I am personally comfortable making certain things available only via the
binary protocol.


On Thu, Dec 20, 2007, Dustin Sallings <dustin at spy.net> said:

> On Dec 20, 2007, at 10:14, Kieran Benton wrote:
>> But it is very convenient to just have to not worry about falling foul
>> of not supported characters in keys. Its obviously an easy matter if  
>> you
>> are building a site that is for use with memcached from the start, but
>> if you are moving to memcached from another cache system (as I am)  
>> then
>> it is a bit of a worry if delimiters you have previously been using
>> might now be treated as erroneous.
> 	Understood, but it's a limitation of having a text protocol.  It *is*  
> possible to remove many of the restrictions in the binary protocol,  
> but I don't think it's very desirable to make keys in the binary  
> protocol you can't get/set/delete in the text protocol.  At least, not  
> unless the text protocol becomes deprecated and every client speaks  
> binary.
>> Are we saying that as long as you use UTF-8 for the key, and that it  
>> is
>> not longer that 250 bytes, then all is fine with both text and binary
>> protocols? If so then I think we should update the docs to say so  
>> and be
>> happy :)
> 	In the latest revision, we expanded the space of the key size from 8  
> bits to 16 bits in the protocol.  That's not saying that you can have  
> more than 250 bytes yet, but it means that it's at least possible on  
> the wire.
> -- 
> Dustin Sallings


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