{"id":2414,"date":"2022-08-30T15:24:40","date_gmt":"2022-08-30T15:24:40","guid":{"rendered":"https:\/\/unknownerror.org\/index.php\/2014\/01\/11\/problem-about-cowboy-collection-of-common-programming-errors\/"},"modified":"2022-08-30T15:24:40","modified_gmt":"2022-08-30T15:24:40","slug":"problem-about-cowboy-collection-of-common-programming-errors","status":"publish","type":"post","link":"https:\/\/unknownerror.org\/index.php\/2022\/08\/30\/problem-about-cowboy-collection-of-common-programming-errors\/","title":{"rendered":"problem about cowboy-Collection of common programming errors"},"content":{"rendered":"<ul>\n<li>\n<img decoding=\"async\" src=\"http:\/\/www.gravatar.com\/avatar\/e25dcc6577fb2eae1bd12e9fb94395b2?s=32&amp;d=identicon&amp;r=PG\" \/><br \/>\nJohn Doe<br \/>\nerlang webserver cowboy<br \/>\nTrying out Cowboy (Erlang) http library, helloworld example: https:\/\/github.com\/extend\/cowboy\/tree\/master\/examples\/hello_worldWhen using Apache&#8217;s &#8220;ab&#8221; testing tool in this manner, I get &#8220;connection reset&#8221;:d7 ~\/cb\/cowboy\/examples\/hello_world % !564 ab -n 30000 -c 5000 http:\/\/127.0.0.1:8080\/ This is ApacheBench, Version 2.3 &lt;$Revision: 655654 $&gt; Copyright 1996 Adam Twiss, Zeus Technology Ltd, http:\/\/www.zeustech.net\/ Licensed to The Apache Software Foundation, http:\/\/www.apache.org\/Benchmark<\/li>\n<li>\n<img decoding=\"async\" src=\"http:\/\/i.stack.imgur.com\/IRrox.jpg?s=32&amp;g=1\" \/><br \/>\nmattk<br \/>\nerlang undef cowboy<br \/>\nI am trying to run a custom application but get multiple errors. I believe the main egs app gets an error because it calls the egs patch app which has an undefined type. I cant figure out how to get this working I have tried recompiling the code many times in regards to others with a similar problem but nothing seems to work. The cowboy start listener remains undefined.This is the error I receive.=CRASH REPORT==== 10-Apr-2013::21:02:00 ===crasher:initial call: application_master:init\/4pid: &lt;0<\/li>\n<li>\n<img decoding=\"async\" src=\"http:\/\/www.gravatar.com\/avatar\/42ec7f4297edbaa9c34b969e6bd0f5b4?s=32&amp;d=identicon&amp;r=PG\" \/><br \/>\nsibbl<br \/>\nerlang webserver cowboy<br \/>\nI am currently playing around with minimal web servers, like Cowboy. I want to pass a number in the URL, load lines of a file, sort these lines and print the element in the middle to test IO and sorting. So the code loads the path like \/123, makes a padded &#8220;00123&#8221; out of the number, loads the file &#8220;input00123.txt&#8221; and sorts its content and then returns something like &#8220;input00123.txt 0.50000&#8221;.At the sime time I have a test tool which makes 50 simultaneous requests, where only 2 get answered, t<\/li>\n<li>\n<img decoding=\"async\" src=\"http:\/\/www.gravatar.com\/avatar\/19bec4b9e0e8dbce229d2ab90d2c5041?s=32&amp;d=identicon&amp;r=PG\" \/><br \/>\nuser601836<br \/>\nerlang websocket cowboy<br \/>\nI have seen many examples of chat room systems over websocket implemented with erlang and cowboy. Most of the examples I have seen use gproc. In practice each websocket handler registers itself with gproc and then broadcasts\/receives messages from it.Since a user could close by accident the webpage I am thinking about connecting to the websocket handler a gen_fsm which actually broadcasts\/receives all the messages from gproc. In this way the gen_fsm could switch from a &#8220;connected&#8221; state to a &#8220;di<\/li>\n<li>\n<img decoding=\"async\" src=\"http:\/\/www.gravatar.com\/avatar\/9fd84aebd034efd637dab994442ca38c?s=32&amp;d=identicon&amp;r=PG\" \/><br \/>\ncouchemar<br \/>\nrest erlang cowboy<br \/>\nHow can I enable CORS for cowboy rest handler? I tried to add options\/2 method, like this:options(Req, State) -&gt;{[{&lt;&lt;&#8220;access-control-allow-origin&#8221;&gt;&gt;, &lt;&lt;&#8220;*&#8221;&gt;&gt;},{&lt;&lt;&#8220;access-control-allow-methods&#8221;&gt;&gt;, &lt;&lt;&#8220;GET, OPTIONS&#8221;&gt;&gt;}], Req, State}.but this causes errors like:Error in process &lt;0.263.0&gt; with exit value: {{case_clause,{[{&lt;&lt;27 bytes&gt;&gt;,&lt;&lt;1 byte&gt;&gt;},{&lt;&lt;28 bytes&gt;&gt;,&lt;&lt;12 bytes&gt;&gt;}],{http_req,#Port&lt;0.2<\/li>\n<li>\n<img decoding=\"async\" src=\"http:\/\/www.gravatar.com\/avatar\/d5a1783785adfa87e417fdf3baa39d1c?s=32&amp;d=identicon&amp;r=PG\" \/><br \/>\nMax Grigoriev<br \/>\nerlang cowboy<br \/>\nHow can I set status code in my REST POST resource.Now I&#8217;m doing this make_post(Req, State) -&gt;lager:info(&#8220;post&#8221;),Resp = cowboy_req:set_resp_body(&lt;&lt;&#8220;HELLO POST\\n&#8221;&gt;&gt;, Req),{ok, Resp3} = cowboy_req:reply(201, Resp),{true, Resp3, State}.But I receive such errors:1:43:10.510 [info] [nonode@nohost#pbshare_logic_registration#&lt;0.205.0&gt;] [handle_info#35] :Exit Logic from &lt;0.204.0&gt; Reason: {function_clause,[{cowboy_req,reply,[204,[],&lt;&lt;&gt;&gt;,{http_req,#Port&lt;0.6355&gt;,ranch_tcp,kee<\/li>\n<\/ul>\n<p id=\"rop\"><small>Originally posted 2014-01-11 03:02:55. <\/small><\/p>","protected":false},"excerpt":{"rendered":"<p>John Doe erlang webserver cowboy Trying out Cowboy (Erlang) http library, helloworld example: https:\/\/github.com\/extend\/cowboy\/tree\/master\/examples\/hello_worldWhen using Apache&#8217;s &#8220;ab&#8221; testing tool in this manner, I get &#8220;connection reset&#8221;:d7 ~\/cb\/cowboy\/examples\/hello_world % !564 ab -n 30000 -c 5000 http:\/\/127.0.0.1:8080\/ This is ApacheBench, Version 2.3 &lt;$Revision: 655654 $&gt; Copyright 1996 Adam Twiss, Zeus Technology Ltd, http:\/\/www.zeustech.net\/ Licensed to The Apache [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-2414","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/unknownerror.org\/index.php\/wp-json\/wp\/v2\/posts\/2414","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/unknownerror.org\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/unknownerror.org\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/unknownerror.org\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/unknownerror.org\/index.php\/wp-json\/wp\/v2\/comments?post=2414"}],"version-history":[{"count":0,"href":"https:\/\/unknownerror.org\/index.php\/wp-json\/wp\/v2\/posts\/2414\/revisions"}],"wp:attachment":[{"href":"https:\/\/unknownerror.org\/index.php\/wp-json\/wp\/v2\/media?parent=2414"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/unknownerror.org\/index.php\/wp-json\/wp\/v2\/categories?post=2414"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/unknownerror.org\/index.php\/wp-json\/wp\/v2\/tags?post=2414"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}