Btw, if you own the defrecord, extend a protocol to it directly in its definition, rather than in a separate extend or extend-protocol form. Doing it inline makes the record implement the protocol's backing interface, which will be much more efficient. (If it's not your record you don't really have a choice.)
(defrecord FooRecord [msg] FooProtocol (foo [_] ...)) On Tuesday, January 6, 2015 5:20:17 PM UTC-5, Michael Blume wrote: > > On further investigation, it looks like you're suffering from > http://dev.clojure.org/jira/browse/CLJ-979 -- if I apply the patch for > this bug to clojure and recompile your project everything works fine. It > looks like this patch *is* slated to make it into Clojure 1.7.0, so that > should also make your problem go away. > > On Tue Jan 06 2015 at 1:29:39 PM Michael Blume <blume...@gmail.com > <javascript:>> wrote: > >> TL;DR: If you wait for that lein-ring pull to get merged, you can upgrade >> lein-ring and your problem will go away. If you wait for Clojure 1.7.0 it's >> possible your problem will go away, though I'm less confident here (the >> current alpha doesn't have a fix). If you want your problem to go away >> *right now* then you want your ring handler listed in your project.clj to >> be in a namespace that *doesn't import any of the rest of your project*. >> That's what >> https://github.com/MichaelBlume/extend-test/blob/6a676e6e326a91a1003e76b219b94a2664175587/src/extend_test/core/shim.clj >> >> does. It has an initialize! function which, at run-time, rather than at >> compile-time, manually imports your real handler and sticks it in an atom. >> Then the handler exposed to ring just reads the real handler out of the >> atom and applies it to the incoming request. >> >> >> On Tue Jan 06 2015 at 1:24:40 PM Michael Blume <blume...@gmail.com >> <javascript:>> wrote: >> >>> lein-ring uses AOT compilation to build war files. AOT compilation in >>> clojure is, well, problematic sometimes. Fortunately it can almost always >>> be avoided using clever indirection. >>> >>> For example: https://github.com/pdenhaan/extend-test/pull/1 builds a >>> war that works =) >>> >>> I've got a pull open against lein-ring that will use this trick by >>> default and avoid AOT in war builds, I'm hoping it'll get merged/released >>> soon. >>> >>> There's a couple open bugs in Clojure right now to do with AOT that have >>> patches that should land in 1.7.0. It's possible one of them will solve >>> your problem, I'm poking at them now to check. >>> >>> >>> On Tue Jan 06 2015 at 8:08:41 AM <peter....@qficonsulting.com >>> <javascript:>> wrote: >>> >>>> I'm a relative newcomer to Clojure, and I'm puzzled by problems I have >>>> using extend in a webapp. Any help would be hugely appreciated. >>>> >>>> My use case is basically this: >>>> >>>> (defrecord FooRecord [msg]) >>>> >>>> >>>> (defprotocol FooProtocol >>>> (bar [foo] "to use with extend-type")) >>>> >>>> >>>> (extend FooRecord >>>> FooProtocol >>>> {:bar (fn [foo] (str "Test " (:msg foo)))}) >>>> >>>> I'm calling bar on a newly created FooRecord: >>>> >>>> (bar (->FooRecord "Successful")) >>>> >>>> This works in a REPL, and also works great in a web application on ring >>>> server-headless: >>>> >>>> Test Successful >>>> >>>> >>>> But the moment I package the code in a war and deploy to Jetty 8 or >>>> Tomcat 7, it fails: >>>> >>>> java.lang.IllegalArgumentException: No implementation of method: >>>>> :bar of protocol: #'extend-test.core.handler/FooProtocol found for >>>>> class: extend_test.core.handler.FooRecord >>>>> clojure.core$_cache_protocol_fn.invoke(core_deftype.clj:544) >>>>> extend_test.core.handler$eval44$fn__45$G__35__50.invoke(hand >>>>> ler.clj:8) >>>>> extend_test.core.handler$fn__65.invoke(handler.clj:16) >>>>> compojure.core$make_route$fn__1431.invoke(core.clj:104) >>>>> ... >>>> >>>> >>>> I searched this group and the web for clues. It smells of a >>>> classloading/aliasing problem, but I could not find any information to >>>> indicate that this behaviour is expected when deploying to a servlet >>>> container, or what I can do about it apart from avoid using extend. >>>> >>>> If you'd like to check out the full code or run it yourself, I've >>>> created a Github project with a minimal test case >>>> <https://github.com/pdenhaan/extend-test>. >>>> >>>> The problem has me altogether stumped for the moment. Thanks for >>>> reading. >>>> >>>> -- >>>> You received this message because you are subscribed to the Google >>>> Groups "Clojure" group. >>>> To post to this group, send email to clo...@googlegroups.com >>>> <javascript:> >>>> Note that posts from new members are moderated - please be patient with >>>> your first post. >>>> To unsubscribe from this group, send email to >>>> clojure+u...@googlegroups.com <javascript:> >>>> For more options, visit this group at >>>> http://groups.google.com/group/clojure?hl=en >>>> --- >>>> You received this message because you are subscribed to the Google >>>> Groups "Clojure" group. >>>> To unsubscribe from this group and stop receiving emails from it, send >>>> an email to clojure+u...@googlegroups.com <javascript:>. >>>> For more options, visit https://groups.google.com/d/optout. >>>> >>> -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups "Clojure" group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
