For debugging purposes we dynamic register verb handlers with the servers to get certain kinds of information that would be of interest. I do not know how we could do the same with enums. Maybe there is some esoteric way, that I am not aware of, to achieve this. Basically we stick in an entry to the map of registered verb handlers where the key is a string. Avinash
On Sat, Mar 28, 2009 at 11:47 AM, Jonathan ellis <[email protected]> wrote: > My problem is I am severely allergic to boilerplate code. :) But it does > sound like the thrift idea isn't going to work. > > What about the tangential idea of using enums for handler type instead of > strings? > > -Jonathan > > > On Mar 28, 2009, at 12:49 PM, Avinash Lakshman <[email protected]> > wrote: > > Given that we need super control over the serialization process in some >> conditions and do not any in most other situations I am not sure what is >> the >> best solution here. Maybe a hybrid and that would be crazy. Fundamentally >> I >> think this is a triviality and this mechanism is really brain dead simple. >> Your point about tests is very very well taken. In our defense if we had >> religiously written tests I do not think we would have been where we are >> w.r.t to where the system is now :). We have a slew of tests that we do >> have >> but they are super well written but rather ad-hoc and I do not mean the >> main() that you see in most other places. >> Avinash >> >> On Sat, Mar 28, 2009 at 10:39 AM, Avinash Lakshman < >> [email protected]> wrote: >> >> For eg Thrift will definitely not help in the messages that we use for >>> the >>> membership protocol. Because there we need to control how big the >>> serialized >>> messages are - we make sure we serialize a part of the object such that >>> it >>> fits into an ethernet MTU packet. We do this so that we don't get bitten >>> by >>> UDP fragmentation. I don't think you could do operations like that in >>> Thrift >>> based serialization mechanism. We need more control over the >>> serialization >>> mechanism. >>> >>> So I don't know if this is something that is insanely important in any >>> capacity in my opinion. I am sure there are bunch of other reasons I can >>> come up with - we went through this exercise 2 year back. Of course if >>> you >>> want to investigate the efficacy I can't stop you from doing so :). >>> >>> Avinash >>> >>> >>> On Sat, Mar 28, 2009 at 9:48 AM, Jonathan Ellis <[email protected]> >>> wrote: >>> >>> One point of clarification -- I don't understand why looking up by >>>> string is better than using an enum, for instance. java will autobox >>>> enums for use in a hashmap lookup. >>>> >>>> On Sat, Mar 28, 2009 at 10:34 AM, Avinash Lakshman >>>> <[email protected]> wrote: >>>> >>>>> Why is it ad-hoc? And it uses a factory pattern and I don't think it >>>>> >>>> hard >>>> >>>>> once you get a hang of it. Consumers of the system are not even going >>>>> to >>>>> know about these details. Personally I am never a fan of fixing >>>>> anything >>>>> that is not broken - in this case it has been working really well for >>>>> >>>> us. >>>> >>>>> This is now just a matter of what one might prefer. Thrift is something >>>>> >>>> that >>>> >>>>> I would not like to see anywhere apart from the entry point. With >>>>> >>>> regards to >>>> >>>>> the using the string to lookup the handlers it was done because if you >>>>> >>>> don't >>>> >>>>> do that then you will have to resort to RPC style instead of message >>>>> >>>> passing >>>> >>>>> or find the handlers based on the kind of messages i.e if-else >>>>> >>>> branching. We >>>> >>>>> use non-blocking I/O for all our internal messaging and Thrift using >>>>> blocking I/O. There is big difference in throughput and also Thrift >>>>> non-blocking I/O from what I hear is horrendous in performance and >>>>> stability. My friend you don't have my vote for this :). >>>>> Avinash >>>>> >>>>> On Sat, Mar 28, 2009 at 8:11 AM, Jonathan Ellis <[email protected]> >>>>> >>>> wrote: >>>> >>>>> >>>>> we have a Message class that mostly represents a bunch of bytes (but >>>>>> sometimes does not, which in some cases causes bugs) and a bunch of >>>>>> other *Message classes that are not Message subclasses but generate >>>>>> Message objects (so you have the amusingly redundant Message message = >>>>>> readResponseMessage.makeReadResponseMessage() in places). >>>>>> >>>>>> I think we can replace these ad-hoc and tedious-to-write Message >>>>>> factories with generated thrift code. Thrift is good at this and >>>>>> efficient (currently our message identifiers are inefficient strings >>>>>> like "ROW-READ-VERB-HANDLER"). >>>>>> >>>>>> Any objections to investigating replacing the hand-coded messages with >>>>>> thrift? >>>>>> >>>>>> >>>>> >>>> >>> >>>
