Re: core.async | compojure ... odd error ... help!!
Jet supports what you were trying to do, it accepts a channel as return value to send the response to the client, and in the :body of the response (no matter the kind of response via a channel or map) to trigger chunked responses. see here https://github.com/mpenet/jet#ring-async On Saturday, September 27, 2014 8:08:48 PM UTC+2, mond wrote: Thanks for the tips. I wasn't expecting magic but otherwise your points are well taken Ray Sent from my iPhone On 27 Sep 2014, at 16:55, James Reeves ja...@booleanknot.com javascript: wrote: On 27 September 2014 10:01, mond r...@mcdermott.be javascript: wrote: Speaking to the main point, no I don't want to put a channel on to the response so that's a mistake that I see and would like to avoid. I would like to understand where I have gone wrong. You're trying to use core.async with a library that has no understanding of core.async. It's important to understand that core.async isn't magic; it won't work with libraries that weren't designed for it. Maybe I need to use HTTPkit instead? HTTP Kit has good support for async, but uses its own lightweight protocol. Check out the examples on their website, and if you still want to connect a core.async channel up to HTTP Kit, you'll need something like: (async/take! async-ch (fn [msg] (httpkit/send! http-ch msg))) This tells core.async to take values off the async channel and pass them onto HTTP Kit. - James -- 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.
Re: core.async | compojure ... odd error ... help!!
Jet supports what you were trying to do, it accepts a channel as return value to send the response to the client, and in the :body of the response (no matter the kind of response via a channel or map) to trigger chunked responses. see here https://github.com/mpenet/jet#ring-async On Saturday, September 27, 2014 8:08:48 PM UTC+2, mond wrote: Thanks for the tips. I wasn't expecting magic but otherwise your points are well taken Ray Sent from my iPhone On 27 Sep 2014, at 16:55, James Reeves ja...@booleanknot.com javascript: wrote: On 27 September 2014 10:01, mond r...@mcdermott.be javascript: wrote: Speaking to the main point, no I don't want to put a channel on to the response so that's a mistake that I see and would like to avoid. I would like to understand where I have gone wrong. You're trying to use core.async with a library that has no understanding of core.async. It's important to understand that core.async isn't magic; it won't work with libraries that weren't designed for it. Maybe I need to use HTTPkit instead? HTTP Kit has good support for async, but uses its own lightweight protocol. Check out the examples on their website, and if you still want to connect a core.async channel up to HTTP Kit, you'll need something like: (async/take! async-ch (fn [msg] (httpkit/send! http-ch msg))) This tells core.async to take values off the async channel and pass them onto HTTP Kit. - James -- 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.
Re: core.async | compojure ... odd error ... help!!
Excellent - thanks. Nice to see core.async getting the ring middleware love :) On 28 Sep 2014 at 10:48:57, Max Penet (m...@qbits.cc) wrote: Jet supports what you were trying to do, it accepts a channel as return value to send the response to the client, and in the :body of the response (no matter the kind of response via a channel or map) to trigger chunked responses. see here https://github.com/mpenet/jet#ring-async On Saturday, September 27, 2014 8:08:48 PM UTC+2, mond wrote: Thanks for the tips. I wasn't expecting magic but otherwise your points are well taken Ray Sent from my iPhone On 27 Sep 2014, at 16:55, James Reeves ja...@booleanknot.com wrote: On 27 September 2014 10:01, mond r...@mcdermott.be wrote: Speaking to the main point, no I don't want to put a channel on to the response so that's a mistake that I see and would like to avoid. I would like to understand where I have gone wrong. You're trying to use core.async with a library that has no understanding of core.async. It's important to understand that core.async isn't magic; it won't work with libraries that weren't designed for it. Maybe I need to use HTTPkit instead? HTTP Kit has good support for async, but uses its own lightweight protocol. Check out the examples on their website, and if you still want to connect a core.async channel up to HTTP Kit, you'll need something like: (async/take! async-ch (fn [msg] (httpkit/send! http-ch msg))) This tells core.async to take values off the async channel and pass them onto HTTP Kit. - James -- 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 a topic in the Google Groups Clojure group. To unsubscribe from this topic, visit https://groups.google.com/d/topic/clojure/gOsd2Zzc1Vk/unsubscribe. To unsubscribe from this group and all its topics, send an email to clojure+unsubscr...@googlegroups.com. 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.
Re: core.async | compojure ... odd error ... help!!
Hi mond, I've been using HTTPkit with Compojure and core.async (all fronted by Nginx so the entire stack is async FWIW). To glue core.async with HTTPkit when handling inbound requests, I have a utility function (defn handle-async! [handler req] (http-server/with-channel req channel (take! (handler req) #(http-server/send! channel % and I make use of that utility function when defining routes (defroutes all-routes (GET /covers/v1/:cover [] (partial http/handle-async! fetch-cover!)) (context /books/v1 [] (GET /search [] (partial http/handle-async! search-handler!)) (GET /:isbn [] (partial http/handle-async! get-book-by-isbn! The handler functions fetch-cover!, search-handler!, get-book-by-isbn!, all return channels (they either call go for stuff that needs to be async, or to-chan on collections read directly from memory. - Mike On Saturday, September 27, 2014 5:01:36 AM UTC-4, mond wrote: Hi James, Er, nice tip on the routes - that was another thing that I didn't expect to work but was happy when it did ;-) I will of course adapt it to your recommendation. Speaking to the main point, no I don't want to put a channel on to the response so that's a mistake that I see and would like to avoid. I would like to understand where I have gone wrong. Maybe I need to use HTTPkit instead? Thanks Ray On Saturday, 27 September 2014 02:08:50 UTC+2, James Reeves wrote: Hi Ray, I don't entirely understand why you expected this to work. Channels aren't a valid Ring response body. The error message is essentially telling you that Compojure has no way of turning the channel object you've returned into a valid response. The other problem you have is that the Ring Jetty adapter doesn't have any support for asynchronous operations. Another small point. You're using * as an argument name, but this isn't really recommended. This only works by coincidence, and it may be removed in future versions. Instead use something like: (GET [/:brand/:country/:resource :resource #.*] [brand country resource] ...) - James On 27 September 2014 00:14, mond r...@mcdermott.be wrote: My first core.async program ... all works outside of the web app but barfs once I put the functions inside a web container. I hope somebody in the group can point to my obvious mistake... The idea is that the function 'respond-within-sla' will give back a result or a come back later message after N milliseconds. It is passed a number of ms, three functions and the arguments for the final function ... which is the one that should operate within the SLA. (defn respond-within-sla [expected-result-milliseconds respond-ok respond-later data-fetcher args] (let [data-channel (timeout expected-result-milliseconds)] (go (if-let [data (!! data-channel)] ((async/close! data-channel) (respond-ok data)) (respond-later))) (go (! data-channel (apply data-fetcher args) To keep the volume of code to parse to a minimum I have made a few toy functions that demonstrate the failure... ; test funcs (defn ok [data] (prn (str send HTTP 200 ... got data data))) (defn later [] (prn (str send HTTP 202 ... request received, come back later))) (defn fetcher [arg1 arg2 arg3] (prn (str fetching data with args arg1 arg2 arg3)) response-data) (defn failer [ args] (Thread/sleep 1000) (str never gets here args)) ; test funcs (defn ok [data] (prn (str send HTTP 200 ... got data data))) (defn later [] (prn (str send HTTP 202 ... request received, come back later))) (defn fetcher [arg1 arg2 arg3] (prn (str fetching data with args arg1 arg2 arg3)) response-data) (defn failer [ args] (Thread/sleep 1000) (str never gets here args)) (defn generate-response [brand country resource] (let [sla (or (env :sla-milliseconds) 100)] (respond-within-sla sla ok later fetcher brand country resource))) (defn generate-fail [brand country resource] (let [sla (or (env :sla-milliseconds) 100)] (respond-within-sla sla ok later failer brand country resource))) From within the REPL it all works fine... (generate-response A B C) = #ManyToManyChannel clojure.core.async.impl.channels.ManyToManyChannel@4b7ae3f7 fetching data with args A B C send HTTP 200 ... got data response-data (generate-fail A B C) = #ManyToManyChannel clojure.core.async.impl.channels.ManyToManyChannel@4eb8b5a9 send HTTP 202 ... request received, come back later Here is the compojure route.. (defroutes app (GET /:brand/:country/* [brand country *] (generate-response brand country *)) (ANY * [] (route/not-found You must use a REST style to specify brand and country keys in the URL))) If I now start it up 'lein run' and try to exercise the functions from
Re: core.async | compojure ... odd error ... help!!
Hi James, Er, nice tip on the routes - that was another thing that I didn't expect to work but was happy when it did ;-) I will of course adapt it to your recommendation. Speaking to the main point, no I don't want to put a channel on to the response so that's a mistake that I see and would like to avoid. I would like to understand where I have gone wrong. Maybe I need to use HTTPkit instead? Thanks Ray On Saturday, 27 September 2014 02:08:50 UTC+2, James Reeves wrote: Hi Ray, I don't entirely understand why you expected this to work. Channels aren't a valid Ring response body. The error message is essentially telling you that Compojure has no way of turning the channel object you've returned into a valid response. The other problem you have is that the Ring Jetty adapter doesn't have any support for asynchronous operations. Another small point. You're using * as an argument name, but this isn't really recommended. This only works by coincidence, and it may be removed in future versions. Instead use something like: (GET [/:brand/:country/:resource :resource #.*] [brand country resource] ...) - James On 27 September 2014 00:14, mond r...@mcdermott.be javascript: wrote: My first core.async program ... all works outside of the web app but barfs once I put the functions inside a web container. I hope somebody in the group can point to my obvious mistake... The idea is that the function 'respond-within-sla' will give back a result or a come back later message after N milliseconds. It is passed a number of ms, three functions and the arguments for the final function ... which is the one that should operate within the SLA. (defn respond-within-sla [expected-result-milliseconds respond-ok respond-later data-fetcher args] (let [data-channel (timeout expected-result-milliseconds)] (go (if-let [data (!! data-channel)] ((async/close! data-channel) (respond-ok data)) (respond-later))) (go (! data-channel (apply data-fetcher args) To keep the volume of code to parse to a minimum I have made a few toy functions that demonstrate the failure... ; test funcs (defn ok [data] (prn (str send HTTP 200 ... got data data))) (defn later [] (prn (str send HTTP 202 ... request received, come back later))) (defn fetcher [arg1 arg2 arg3] (prn (str fetching data with args arg1 arg2 arg3)) response-data) (defn failer [ args] (Thread/sleep 1000) (str never gets here args)) ; test funcs (defn ok [data] (prn (str send HTTP 200 ... got data data))) (defn later [] (prn (str send HTTP 202 ... request received, come back later))) (defn fetcher [arg1 arg2 arg3] (prn (str fetching data with args arg1 arg2 arg3)) response-data) (defn failer [ args] (Thread/sleep 1000) (str never gets here args)) (defn generate-response [brand country resource] (let [sla (or (env :sla-milliseconds) 100)] (respond-within-sla sla ok later fetcher brand country resource))) (defn generate-fail [brand country resource] (let [sla (or (env :sla-milliseconds) 100)] (respond-within-sla sla ok later failer brand country resource))) From within the REPL it all works fine... (generate-response A B C) = #ManyToManyChannel clojure.core.async.impl.channels.ManyToManyChannel@4b7ae3f7 fetching data with args A B C send HTTP 200 ... got data response-data (generate-fail A B C) = #ManyToManyChannel clojure.core.async.impl.channels.ManyToManyChannel@4eb8b5a9 send HTTP 202 ... request received, come back later Here is the compojure route.. (defroutes app (GET /:brand/:country/* [brand country *] (generate-response brand country *)) (ANY * [] (route/not-found You must use a REST style to specify brand and country keys in the URL))) If I now start it up 'lein run' and try to exercise the functions from the web server... $ curl -I http://localhost:5000/A/B/D.jpg HTTP/1.1 500 Server Error Date: Fri, 26 Sep 2014 23:02:03 GMT Content-Length: 0 Connection: close Server: Jetty(7.6.8.v20121106) And on the server I see this: $ lein run Compiling redirector.web 2014-09-27 01:01:48.426:INFO:oejs.Server:jetty-7.6.8.v20121106 2014-09-27 01:01:48.458:INFO:oejs.AbstractConnector:Started SelectChannelConnector@0.0.0.0:5000 2014-09-27 01:02:03.535:WARN:oejs.AbstractHttpConnection:/A/B/D.jpg java.lang.IllegalArgumentException: No implementation of method: :render of protocol: #'compojure.response/Renderable found for class: clojure.core.async.impl.channels.ManyToManyChannel at clojure.core$_cache_protocol_fn.invoke(core_deftype.clj:544) at compojure.response$fn__213$G__208__220.invoke(response.clj:9) at compojure.core$make_route$fn__332.invoke(core.clj:100) at compojure.core$if_route$fn__320.invoke(core.clj:46) at compojure.core$if_method$fn__313.invoke(core.clj:33) at
Re: core.async | compojure ... odd error ... help!!
On 27 September 2014 10:01, mond r...@mcdermott.be wrote: Speaking to the main point, no I don't want to put a channel on to the response so that's a mistake that I see and would like to avoid. I would like to understand where I have gone wrong. You're trying to use core.async with a library that has no understanding of core.async. It's important to understand that core.async isn't magic; it won't work with libraries that weren't designed for it. Maybe I need to use HTTPkit instead? HTTP Kit has good support for async, but uses its own lightweight protocol. Check out the examples on their website, and if you still want to connect a core.async channel up to HTTP Kit, you'll need something like: (async/take! async-ch (fn [msg] (httpkit/send! http-ch msg))) This tells core.async to take values off the async channel and pass them onto HTTP Kit. - James -- 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.
Re: core.async | compojure ... odd error ... help!!
Thanks for the tips. I wasn't expecting magic but otherwise your points are well taken Ray Sent from my iPhone On 27 Sep 2014, at 16:55, James Reeves ja...@booleanknot.com wrote: On 27 September 2014 10:01, mond r...@mcdermott.be wrote: Speaking to the main point, no I don't want to put a channel on to the response so that's a mistake that I see and would like to avoid. I would like to understand where I have gone wrong. You're trying to use core.async with a library that has no understanding of core.async. It's important to understand that core.async isn't magic; it won't work with libraries that weren't designed for it. Maybe I need to use HTTPkit instead? HTTP Kit has good support for async, but uses its own lightweight protocol. Check out the examples on their website, and if you still want to connect a core.async channel up to HTTP Kit, you'll need something like: (async/take! async-ch (fn [msg] (httpkit/send! http-ch msg))) This tells core.async to take values off the async channel and pass them onto HTTP Kit. - James -- 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.
core.async | compojure ... odd error ... help!!
My first core.async program ... all works outside of the web app but barfs once I put the functions inside a web container. I hope somebody in the group can point to my obvious mistake... The idea is that the function 'respond-within-sla' will give back a result or a come back later message after N milliseconds. It is passed a number of ms, three functions and the arguments for the final function ... which is the one that should operate within the SLA. (defn respond-within-sla [expected-result-milliseconds respond-ok respond-later data-fetcher args] (let [data-channel (timeout expected-result-milliseconds)] (go (if-let [data (!! data-channel)] ((async/close! data-channel) (respond-ok data)) (respond-later))) (go (! data-channel (apply data-fetcher args) To keep the volume of code to parse to a minimum I have made a few toy functions that demonstrate the failure... ; test funcs (defn ok [data] (prn (str send HTTP 200 ... got data data))) (defn later [] (prn (str send HTTP 202 ... request received, come back later))) (defn fetcher [arg1 arg2 arg3] (prn (str fetching data with args arg1 arg2 arg3)) response-data) (defn failer [ args] (Thread/sleep 1000) (str never gets here args)) ; test funcs (defn ok [data] (prn (str send HTTP 200 ... got data data))) (defn later [] (prn (str send HTTP 202 ... request received, come back later))) (defn fetcher [arg1 arg2 arg3] (prn (str fetching data with args arg1 arg2 arg3)) response-data) (defn failer [ args] (Thread/sleep 1000) (str never gets here args)) (defn generate-response [brand country resource] (let [sla (or (env :sla-milliseconds) 100)] (respond-within-sla sla ok later fetcher brand country resource))) (defn generate-fail [brand country resource] (let [sla (or (env :sla-milliseconds) 100)] (respond-within-sla sla ok later failer brand country resource))) From within the REPL it all works fine... (generate-response A B C) = #ManyToManyChannel clojure.core.async.impl.channels.ManyToManyChannel@4b7ae3f7 fetching data with args A B C send HTTP 200 ... got data response-data (generate-fail A B C) = #ManyToManyChannel clojure.core.async.impl.channels.ManyToManyChannel@4eb8b5a9 send HTTP 202 ... request received, come back later Here is the compojure route.. (defroutes app (GET /:brand/:country/* [brand country *] (generate-response brand country *)) (ANY * [] (route/not-found You must use a REST style to specify brand and country keys in the URL))) If I now start it up 'lein run' and try to exercise the functions from the web server... $ curl -I http://localhost:5000/A/B/D.jpg HTTP/1.1 500 Server Error Date: Fri, 26 Sep 2014 23:02:03 GMT Content-Length: 0 Connection: close Server: Jetty(7.6.8.v20121106) And on the server I see this: $ lein run Compiling redirector.web 2014-09-27 01:01:48.426:INFO:oejs.Server:jetty-7.6.8.v20121106 2014-09-27 01:01:48.458:INFO:oejs.AbstractConnector:Started SelectChannelConnector@0.0.0.0:5000 2014-09-27 01:02:03.535:WARN:oejs.AbstractHttpConnection:/A/B/D.jpg java.lang.IllegalArgumentException: No implementation of method: :render of protocol: #'compojure.response/Renderable found for class: clojure.core.async.impl.channels.ManyToManyChannel at clojure.core$_cache_protocol_fn.invoke(core_deftype.clj:544) at compojure.response$fn__213$G__208__220.invoke(response.clj:9) at compojure.core$make_route$fn__332.invoke(core.clj:100) at compojure.core$if_route$fn__320.invoke(core.clj:46) at compojure.core$if_method$fn__313.invoke(core.clj:33) at compojure.core$routing$fn__338.invoke(core.clj:113) at clojure.core$some.invoke(core.clj:2515) at compojure.core$routing.doInvoke(core.clj:113) at clojure.lang.RestFn.applyTo(RestFn.java:139) at clojure.core$apply.invoke(core.clj:626) at compojure.core$routes$fn__342.invoke(core.clj:118) at clojure.lang.Var.invoke(Var.java:379) at ring.middleware.keyword_params$wrap_keyword_params$fn__534.invoke(keyword_params.clj:35) at ring.middleware.nested_params$wrap_nested_params$fn__576.invoke(nested_params.clj:84) at ring.middleware.params$wrap_params$fn__507.invoke(params.clj:64) at ring.middleware.multipart_params$wrap_multipart_params$fn__612.invoke(multipart_params.clj:118) at ring.middleware.flash$wrap_flash$fn__1286.invoke(flash.clj:35) at ring.middleware.session$wrap_session$fn__1273.invoke(session.clj:98) at ring.adapter.jetty$proxy_handler$fn__1426.invoke(jetty.clj:18) at ring.adapter.jetty.proxy$org.eclipse.jetty.server.handler.AbstractHandler$ff19274a.handle(Unknown Source) at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:116) at org.eclipse.jetty.server.Server.handle(Server.java:363) at org.eclipse.jetty.server.AbstractHttpConnection.handleRequest(AbstractHttpConnection.java:483) at
Re: core.async | compojure ... odd error ... help!!
Hi Ray, I don't entirely understand why you expected this to work. Channels aren't a valid Ring response body. The error message is essentially telling you that Compojure has no way of turning the channel object you've returned into a valid response. The other problem you have is that the Ring Jetty adapter doesn't have any support for asynchronous operations. Another small point. You're using * as an argument name, but this isn't really recommended. This only works by coincidence, and it may be removed in future versions. Instead use something like: (GET [/:brand/:country/:resource :resource #.*] [brand country resource] ...) - James On 27 September 2014 00:14, mond r...@mcdermott.be wrote: My first core.async program ... all works outside of the web app but barfs once I put the functions inside a web container. I hope somebody in the group can point to my obvious mistake... The idea is that the function 'respond-within-sla' will give back a result or a come back later message after N milliseconds. It is passed a number of ms, three functions and the arguments for the final function ... which is the one that should operate within the SLA. (defn respond-within-sla [expected-result-milliseconds respond-ok respond-later data-fetcher args] (let [data-channel (timeout expected-result-milliseconds)] (go (if-let [data (!! data-channel)] ((async/close! data-channel) (respond-ok data)) (respond-later))) (go (! data-channel (apply data-fetcher args) To keep the volume of code to parse to a minimum I have made a few toy functions that demonstrate the failure... ; test funcs (defn ok [data] (prn (str send HTTP 200 ... got data data))) (defn later [] (prn (str send HTTP 202 ... request received, come back later))) (defn fetcher [arg1 arg2 arg3] (prn (str fetching data with args arg1 arg2 arg3)) response-data) (defn failer [ args] (Thread/sleep 1000) (str never gets here args)) ; test funcs (defn ok [data] (prn (str send HTTP 200 ... got data data))) (defn later [] (prn (str send HTTP 202 ... request received, come back later))) (defn fetcher [arg1 arg2 arg3] (prn (str fetching data with args arg1 arg2 arg3)) response-data) (defn failer [ args] (Thread/sleep 1000) (str never gets here args)) (defn generate-response [brand country resource] (let [sla (or (env :sla-milliseconds) 100)] (respond-within-sla sla ok later fetcher brand country resource))) (defn generate-fail [brand country resource] (let [sla (or (env :sla-milliseconds) 100)] (respond-within-sla sla ok later failer brand country resource))) From within the REPL it all works fine... (generate-response A B C) = #ManyToManyChannel clojure.core.async.impl.channels.ManyToManyChannel@4b7ae3f7 fetching data with args A B C send HTTP 200 ... got data response-data (generate-fail A B C) = #ManyToManyChannel clojure.core.async.impl.channels.ManyToManyChannel@4eb8b5a9 send HTTP 202 ... request received, come back later Here is the compojure route.. (defroutes app (GET /:brand/:country/* [brand country *] (generate-response brand country *)) (ANY * [] (route/not-found You must use a REST style to specify brand and country keys in the URL))) If I now start it up 'lein run' and try to exercise the functions from the web server... $ curl -I http://localhost:5000/A/B/D.jpg HTTP/1.1 500 Server Error Date: Fri, 26 Sep 2014 23:02:03 GMT Content-Length: 0 Connection: close Server: Jetty(7.6.8.v20121106) And on the server I see this: $ lein run Compiling redirector.web 2014-09-27 01:01:48.426:INFO:oejs.Server:jetty-7.6.8.v20121106 2014-09-27 01:01:48.458:INFO:oejs.AbstractConnector:Started SelectChannelConnector@0.0.0.0:5000 2014-09-27 01:02:03.535:WARN:oejs.AbstractHttpConnection:/A/B/D.jpg java.lang.IllegalArgumentException: No implementation of method: :render of protocol: #'compojure.response/Renderable found for class: clojure.core.async.impl.channels.ManyToManyChannel at clojure.core$_cache_protocol_fn.invoke(core_deftype.clj:544) at compojure.response$fn__213$G__208__220.invoke(response.clj:9) at compojure.core$make_route$fn__332.invoke(core.clj:100) at compojure.core$if_route$fn__320.invoke(core.clj:46) at compojure.core$if_method$fn__313.invoke(core.clj:33) at compojure.core$routing$fn__338.invoke(core.clj:113) at clojure.core$some.invoke(core.clj:2515) at compojure.core$routing.doInvoke(core.clj:113) at clojure.lang.RestFn.applyTo(RestFn.java:139) at clojure.core$apply.invoke(core.clj:626) at compojure.core$routes$fn__342.invoke(core.clj:118) at clojure.lang.Var.invoke(Var.java:379) at ring.middleware.keyword_params$wrap_keyword_params$fn__534.invoke(keyword_params.clj:35) at ring.middleware.nested_params$wrap_nested_params$fn__576.invoke(nested_params.clj:84) at
