The mina: component is a transport for working with Apache MINA
mina:tcp://hostname[:port][?options] mina:udp://hostname[:port][?options] mina:vm://hostname[:port][?options]
From Fuse Mediation Router 1.3 onwards you can specify a codec in the Registry using the codec option. If you are
using TCP and no codec is specified then the textline
flag is used to
determine if text line based codec or object serialization should be used instead. By
default the object serialization is used.
For UDP, if no codec is specified the default uses a basic
ByteBuffer
based codec.
The VM protocol is used as a direct forwarding mechanism in the same JVM. See the MINA VM-Pipe API documentation for details.
A Mina producer has a default timeout value of 30 seconds, while it waits for a response from the remote server.
In normal use, camel-mina
only supports marshalling the body
content—essage headers and exchange properties are not sent. However, the option,
transferExchange, does allow you to transfer the
exchange itself over the wire. See options below.
You can append query options to the URI in the following format,
?option=value&option=value&...
Option | Default Value | Description |
---|---|---|
codec
|
null
|
As of 1.3, you can refer to a named ProtocolCodecFactory
instance in your Registry such as your Spring
ApplicationContext , which is then used for the
marshalling. |
codec
|
null
|
Fuse Mediation Router 2.0: You must use the
# notation to look up your codec in the Registry. For example, use
#myCodec to look up a bean with the id
value, myCodec . |
disconnect
|
false
|
Camel 2.3: Whether or not to disconnect(close) from Mina session right after use. Can be used for both consumer and producer. |
textline
|
false
|
Only used for TCP. If no codec is specified, you can use this flag in 1.3 or
later to indicate a text line based codec; if not specified or the value is
false , then Object Serialization is assumed over TCP.
|
textlineDelimiter
|
DEFAULT
|
Fuse Mediation Router 1.6.0/2.0 Only used for TCP and if
textline=true. Sets the text line delimiter
to use. Possible values are: DEFAULT ,
AUTO , WINDOWS , UNIX or
MAC . If none provided, Fuse Mediation Router will use
DEFAULT . This delimiter is used to mark the end of text.
|
sync
|
true
|
As of 1.3, you can configure the exchange pattern to be either InOnly (default)
or InOut. Setting sync=true means a synchronous exchange
(InOut), where the client can read the response from MINA (the exchange Out
message). The default value has changed in Fuse Mediation Router 1.5 to
true . In older releases, the default value is
false . |
lazySessionCreation
|
See description | As of 1.3, sessions can be lazily created to avoid exceptions, if the remote
server is not up and running when the Fuse Mediation Router producer is started. From
Fuse Mediation Router 2.0 onwards, the default is true . In Fuse Mediation Router 1.x,
the default is false . |
timeout
|
30000
|
As of 1.3, you can configure the timeout that specifies how long to wait for a response from a remote server. The timeout unit is in milliseconds, so 60000 is 60 seconds. The timeout is only used for Mina producer. |
encoding
|
JVM Default | As of 1.3, you can configure the encoding (a charset name) to use for the TCP textline codec and the UDP protocol. If not provided, Fuse Mediation Router will use the JVM default Charset. |
transferExchange
|
false
|
Only used for TCP. As of 1.3, you can transfer the exchange over the wire
instead of just the body. The following fields are transferred: In body, Out
body, fault body, In headers, Out headers, fault headers, exchange properties,
exchange exception. This requires that the objects are
serializable. Fuse Mediation Router will exclude any
non-serializable objects and log it at WARN level. |
minaLogger
|
false
|
As of 1.3, you can enable the Apache MINA logging filter. Apache MINA uses
slf4j logging at INFO level to log all
input and output. |
filters
|
null
|
As of 2.0, you can set a list of Mina IoFilters to
register. The
|
encoderMaxLineLength
|
-1
|
As of 2.1, you can set the textline protocol encoder max line length. By
default the default value of Mina itself is used which are
Integer.MAX_VALUE . |
decoderMaxLineLength
|
-1
|
As of 2.1, you can set the textline protocol decoder max line length. By default the default value of Mina itself is used which are 1024. |
allowDefaultCodec
|
true
|
The mina component installs a default codec if both, codec
is null and textline is
false . Setting allowDefaultCodec to
false prevents the mina component from installing a
default codec as the first element in the filter chain. This is useful in
scenarios where another filter must be the first in the filter chain, like the
SSL filter. |
disconnectOnNoReply
|
true
|
Camel 2.3: If sync is enabled then this option dictates MinaConsumer if it should disconnect where there is no reply to send back. |
noReplyLogLevel
|
WARN
|
Camel 2.3: If sync is enabled this option
dictates MinaConsumer which logging level to use when logging a there is no
reply to send back. Values are: FATAL, ERROR, INFO, DEBUG,
OFF . |
In Fuse Mediation Router 2.0 the codec option must
use #
notation for lookup of the codec bean in the Registry. In Fuse Mediation Router 2.0 the lazySessionCreation option now defaults to
true
.
In Fuse Mediation Router 1.5 the sync
option has changed its
default value from false
to true
, as we felt it
was confusing for end-users when they used Mina to
call remote servers and Fuse Mediation Router wouldn't wait for the response.
In Fuse Mediation Router 1.4 or later codec=textline
is no
longer supported. Use the textline=true
option instead.
See the Mina documentation how to write your own codec. To use your custom codec
with camel-mina
, you should register your codec in the Registry; for example, by creating a bean in the Spring
XML file. Then use the codec
option to specify the bean ID of your
codec. See HL7 that has a custom codec.
In this sample, Fuse Mediation Router exposes a service that listens for TCP connections on port 6200. We use the textline codec. In our route, we create a Mina consumer endpoint that listens on port 6200:
from("mina:tcp://localhost:6200?textline=true&sync=false").to("mock:result");
As the sample is part of a unit test, we test it by sending some data to it on port 6200.
MockEndpoint mock = getMockEndpoint("mock:result"); mock.expectedBodiesReceived("Hello World"); template.sendBody("mina:tcp://localhost:6200?textline=true&sync=false", "Hello World"); assertMockEndpointsSatisfied();
In the next sample, we have a more common use case where we expose a TCP service on
port 6201 also use the textline codec. However, this time we want to return a response,
so we set the sync
option to true
on the consumer.
from("mina:tcp://localhost:6201?textline=true&sync=true").process(new Processor() { public void process(Exchange exchange) throws Exception { String body = exchange.getIn().getBody(String.class); exchange.getOut().setBody("Bye " + body); } });
Then we test the sample by sending some data and retrieving the response using the
template.requestBody()
method. As we know the response is a
String
, we cast it to String
and can assert
that the response is, in fact, something we have dynamically set in our processor code
logic.
String response = (String)template.requestBody("mina:tcp://localhost:6201?textline=true&sync=true", "World"); assertEquals("Bye World", response);
Spring DSL can, of course, also be used for Mina. In the sample below we expose a TCP server on port 5555:
<route> <from uri="mina:tcp://localhost:5555?textline=true"/> <to uri="bean:myTCPOrderHandler"/> </route>
In the route above, we expose a TCP server on port 5555 using the textline codec. We
let the Spring bean with ID, myTCPOrderHandler
, handle the request
and return a reply. For instance, the handler bean could be implemented as
follows:
public String handleOrder(String payload) { ... return "Order: OK" }
Available as of Fuse Mediation Router 2.0
Configuration of Mina endpoints is now possible using regular Spring bean style configuration in the Spring DSL.
However, in the underlying Apache Mina toolkit, it is relatively difficult to set up
the acceptor and the connector, because you can not use simple
setters. To resolve this difficulty, we leverage the MinaComponent
as
a Spring factory bean to configure this for us. If you really need to configure this
yourself, there are setters on the MinaEndpoint
to set these when
needed.
The sample below shows the factory approach:
<!-- Creating mina endpoints is a bit complex so we reuse MinaComponnet as a factory bean to create our endpoint, this is the easiest to do --> <bean id="myMinaFactory" class="org.apache.camel.component.mina.MinaComponent"> <!-- we must provide a camel context so we refer to it by its id --> <constructor-arg index="0" ref="myCamel"/> </bean> <!-- This is our mina endpoint configured with spring, we will use the factory above to create it for us. The goal is to invoke the createEndpoint method with the mina configuration parameter we defined using the constructor-arg option --> <bean id="myMinaEndpoint" factory-bean="myMinaFactory" factory-method="createEndpoint"> <!-- and here we can pass it our configuration --> <constructor-arg index="0" ref="myMinaConfig"/> </bean> <!-- this is our mina configuration with plain properties --> <bean id="myMinaConfig" class="org.apache.camel.component.mina.MinaConfiguration"> <property name="protocol" value="tcp"/> <property name="host" value="localhost"/> <property name="port" value="1234"/> <property name="sync" value="false"/> </bean>
And then we can refer to our endpoint directly in the route, as follows:
<route> <!-- here we route from or mina endpoint we have defined above --> <from ref="myMinaEndpoint"/> <to uri="mock:result"/> </route>
Available as of Fuse Mediation Router 1.6.1
When acting as a server you sometimes want to close the session when, for example, a
client conversion is finished. To instruct Fuse Mediation Router to close the session, you should add
a header with the key CamelMinaCloseSessionWhenComplete
set to a
boolean true
value.
For instance, the example below will close the session after it has written the
bye
message back to the client:
from("mina:tcp://localhost:8080?sync=true&textline=true").process(new Processor() { public void process(Exchange exchange) throws Exception { String body = exchange.getIn().getBody(String.class); exchange.getOut().setBody("Bye " + body); exchange.getOut().setHeader(MinaConstants.MINA_CLOSE_SESSION_WHEN_COMPLETE, true); } });
Available since Fuse Mediation Router 2.1 You can get the
IoSession from the message header with this key
MinaEndpoint.HEADER_MINA_IOSESSION
, and also get the local host address
with the key MinaEndpoint.HEADER_LOCAL_ADDRESS
and remote host address with
the key MinaEndpoint.HEADER_REMOTE_ADDRESS
.
Available since Fuse Mediation Router 2.0
Filters permit you to use some Mina Filters, such as SslFilter
. You
can also implement some customized filters. Please note that codec
and logger
are also implemented as Mina filters of type,
IoFilter
. Any filters you may define are appended to the end of
the filter chain; that is, after codec
and
logger
.
For instance, the example below will send a keep-alive message after 10 seconds of inactivity:
public class KeepAliveFilter extends IoFilterAdapter { @Override public void sessionCreated(NextFilter nextFilter, IoSession session) throws Exception { session.setIdleTime(IdleStatus.BOTH_IDLE, 10); nextFilter.sessionCreated(session); } @Override public void sessionIdle(NextFilter nextFilter, IoSession session, IdleStatus status) throws Exception { session.write("NOOP"); // NOOP is a FTP command for keep alive nextFilter.sessionIdle(session, status); } }
As Fuse Mediation Router Mina may use a request-reply scheme, the endpoint as a client would like
to drop some message, such as greeting when the connection is established. For example,
when you connect to an FTP server, you will get a 220
message with a
greeting (220 Welcome to Pure-FTPd
). If you don't drop the message,
your request-reply scheme will be broken.
public class DropGreetingFilter extends IoFilterAdapter { @Override public void messageReceived(NextFilter nextFilter, IoSession session, Object message) throws Exception { if (message instanceof String) { String ftpMessage = (String) message; // "220" is given as greeting. "200 Zzz" is given as a response to "NOOP" (keep alive) if (ftpMessage.startsWith("220") || or ftpMessage.startsWith("200 Zzz")) { // Dropping greeting return; } } nextFilter.messageReceived(session, message); } }
Then, you can configure your endpoint using Spring DSL:
<bean id="myMinaFactory" class="org.apache.camel.component.mina.MinaComponent"> <constructor-arg index="0" ref="camelContext" /> </bean> <bean id="myMinaEndpoint" factory-bean="myMinaFactory" factory-method="createEndpoint"> <constructor-arg index="0" ref="myMinaConfig"/> </bean> <bean id="myMinaConfig" class="org.apache.camel.component.mina.MinaConfiguration"> <property name="protocol" value="tcp" /> <property name="host" value="localhost" /> <property name="port" value="2121" /> <property name="sync" value="true" /> <property name="minaLogger" value="true" /> <property name="filters" ref="listFilters"/> </bean> <bean id="listFilters" class="java.util.ArrayList" > <constructor-arg> <list value-type="org.apache.mina.common.IoFilter"> <bean class="com.example.KeepAliveFilter"/> <bean class="com.example.DropGreetingFilter"/> </list> </constructor-arg> </bean>