how to connect to remote rabbitmq using clojure - clojure

Question

I am using langohr to connect rabbitmq, if I don't specify any connection string, it works well and it connects to local server, but I want to connect to remote server. So I have the following code. I am using connection string of amqp://bigdata:bigdata#s1:5672, s2 is the hostname of the remote server.
let [ a (println rabbitmq-url)
rmq-conn (rmq/connect {:uri rabbitmq-url})
a (println rabbitmq-url)]
But it throws the error of the following
$ lein run
amqp://bigdata:bigdata#s1:5672
Exception in thread "main" java.io.IOException, compiling:(/tmp/form-init589039011205967992.clj:1:71)
at clojure.lang.Compiler.load(Compiler.java:7142)
at clojure.lang.Compiler.loadFile(Compiler.java:7086)
at clojure.main$load_script.invoke(main.clj:274)
at clojure.main$init_opt.invoke(main.clj:279)
at clojure.main$initialize.invoke(main.clj:307)
at clojure.main$null_opt.invoke(main.clj:342)
at clojure.main$main.doInvoke(main.clj:420)
at clojure.lang.RestFn.invoke(RestFn.java:421)
at clojure.lang.Var.invoke(Var.java:383)
at clojure.lang.AFn.applyToHelper(AFn.java:156)
at clojure.lang.Var.applyTo(Var.java:700)
at clojure.main.main(main.java:37)
Caused by: java.io.IOException
at com.rabbitmq.client.impl.AMQChannel.wrap(AMQChannel.java:106)
at com.rabbitmq.client.impl.AMQChannel.wrap(AMQChannel.java:102)
at com.rabbitmq.client.impl.AMQChannel.exnWrappingRpc(AMQChannel.java:124)
at com.rabbitmq.client.impl.AMQConnection.start(AMQConnection.java:376)
at com.rabbitmq.client.impl.recovery.RecoveryAwareAMQConnectionFactory.newConnection(RecoveryAwareAMQConnectionFactory.java:36)
at com.rabbitmq.client.impl.recovery.AutorecoveringConnection.init(AutorecoveringConnection.java:83)
at com.rabbitmq.client.ConnectionFactory.newConnection(ConnectionFactory.java:609)
at com.rabbitmq.client.ConnectionFactory.newConnection(ConnectionFactory.java:651)
at com.novemberain.langohr.Connection.init(Connection.java:92)
at langohr.core$connect.invoke(core.clj:93)
at clojurewerkz.testcom.core$create_message_from_database.invoke(core.clj:33)
at clojurewerkz.testcom.core$create_message_from_database_loop.invoke(core.clj:53)
at clojurewerkz.testcom.core$_main.doInvoke(core.clj:60)
at clojure.lang.RestFn.invoke(RestFn.java:397)
at clojure.lang.Var.invoke(Var.java:375)
at user$eval5.invoke(form-init589039011205967992.clj:1)
at clojure.lang.Compiler.eval(Compiler.java:6703)
at clojure.lang.Compiler.eval(Compiler.java:6693)
at clojure.lang.Compiler.load(Compiler.java:7130)
... 11 more
Caused by: com.rabbitmq.client.ShutdownSignalException: connection error
at com.rabbitmq.utility.ValueOrException.getValue(ValueOrException.java:67)
at com.rabbitmq.utility.BlockingValueOrException.uninterruptibleGetValue(BlockingValueOrException.java:33)
at com.rabbitmq.client.impl.AMQChannel$BlockingRpcContinuation.getReply(AMQChannel.java:343)
at com.rabbitmq.client.impl.AMQChannel.privateRpc(AMQChannel.java:216)
at com.rabbitmq.client.impl.AMQChannel.exnWrappingRpc(AMQChannel.java:118)
... 27 more
Caused by: java.net.SocketException: Connection reset
at java.net.SocketInputStream.read(SocketInputStream.java:189)
at java.net.SocketInputStream.read(SocketInputStream.java:121)
at java.io.BufferedInputStream.fill(BufferedInputStream.java:246)
at java.io.BufferedInputStream.read(BufferedInputStream.java:265)
at java.io.DataInputStream.readUnsignedByte(DataInputStream.java:288)
at com.rabbitmq.client.impl.Frame.readFrom(Frame.java:95)
at com.rabbitmq.client.impl.SocketFrameHandler.readFrame(SocketFrameHandler.java:139)
at com.rabbitmq.client.impl.AMQConnection$MainLoop.run(AMQConnection.java:534)
at java.lang.Thread.run(Thread.java:745)

Answer 1

First, make sure that RabbitMQ is running on the remote server. Second, check if the user that is connecting to that instance has the permission to do so.

Answer 2

The same issue as below: my account doesn't have access to virtual hosts.
RabbitMQ new connection refused due to SocketException

Answer 3

try this code.
First, put these libs into your project.clj
;;rabbitmq client
[com.novemberain/langohr "2.11.0"]
;;logging
[org.clojure/tools.logging "0.2.4"]
Then, make necessary imports in your clj file:
(:require
;logging
[clojure.tools.logging :as log]
;;rabbitmq
[langohr.core :as rmq]
[langohr.channel :as lch]
[langohr.queue :as lq]
[langohr.exchange :as le]
[langohr.basic :as lb] ))
And here is connect function:
(defn get-mq-connect
"This function connects to RabbitMQ.
params example: {:host \"localhost\" :port 5672 :username \"guest\" :password \"guest\" :vhost \"/\"}
Returns: connect object - connection successful, nil - error occured."
[params]
(try
(log/trace params)
(rmq/connect params)
(catch Exception e
(log/error (.getMessage e))
(println "MQ connection error:" (.getMessage e)))))
You can call this function that way:
(let [ params {:host "myhost.com" :port 5672 :username "admin" :password "StrongPassw098" :vhost "/"}
conn (get-mq-connect mq-params)]
(when-not (nil? conn)
(let [ch (lch/open conn)]
(while (not #stop-flag?)
(do
;;put here your code
))
(rmq/close ch)
(rmq/close conn)))))