Extracting the body from an ActiveMQ message via Camel - apache-camel

I have a route using the Spring DSL as such
<camelContext id="camel" xmlns="http://camel.apache.org/schema/spring">
<route>
<from uri="activemq:queue:worker?mapJmsMessage=false" />
<convertBodyTo type="java.lang.String"/>
<setHeader headerName="CamelHttpMethod">
<constant>POST</constant>
</setHeader>
<to uri="http://localhost/queue" />
</route>
</camelContext>
The message type is an ActiveMQTextMessage. I am able to POST the message to the HTTP URL, but what I get seems to be the toString() output:
ActiveMQTextMessage {commandId = 5, responseRequired = false, message....
I would like to call the getText() method on the ActiveMQTextMessage instance to populate the route, but I cannot figure out how to get that method called. I am quite sure I could get this to work in code, but I need to do everything via XML.

Figured out the problem. I had mapJmsMessage=false set to handle an exception a few days ago. I removed it and suddenly it worked fine.

Related

Camel blueprint <setHeader headerName="CamelHttpPath" id="_setHeader1"><el>${header.uriPattern}</el></setHeader> waiting for dependencies

I have the following Camel Context.
<camelContext id="_camuatomicservicecontext" xmlns="http://camel.apache.org/schema/blueprint">
<route id="_camuatomicserviceroute1">
<from id="_from1" uri="direct-vm:camuatomicservice">
<description>accepts vm messages directly </description>
</from>
<log id="_log1" message="Camu Atomic Service body = ${body}, header= ${header.uriPattern}"/>
<!-- <to id="_to1" uri="restlet:protocol:localhost:8189/"/> -->
<setHeader headerName="api.key" id="_setHeader1">
<constant>replace later with properties api.key Does not matter for this poc</constant>
</setHeader>
<setHeader headerName="CamelHttpPath" id="_setOutHeader1">
<el>${header.uriPattern}</el>
</setHeader>
<to id="_to1" pattern="InOut" uri="netty4-http:http:localhost:8189/path"/>
<log id="_log2" message="CamuAtomicService Response body ${body}"/>
</route>
</camelContext>
From the documentation I expect the CamelHttpPath header to override the endpoint configuration "/path" such that calling Facade Services can pass the header.uriPattern in and dynamically change the resource they want to access. The bundle worked fine until I added the setHeader for CamelHttpPath and now getting "Waiting for dependencies." I assume I need to install a feature, but Simple EL in other bundles on that server work already so not sure what feature I need to install.
Instead of I used and it worked fine. The choice was farther down in the options.

Is it possible to read a file after receiving an event?

I'm using a ActiveMQ Broker with built-in Camel Routes. I want to read a file after an Event received.
<pseudo>
from Event A
read File XY
to Event B with Body from File XY
</pseuod>
I simple tried moving files from a temporary directory based on an event but only event B is written. In the Log file are no Exceptions or Error messages.
<camelContext id="camel" xmlns="http://camel.apache.org/schema/spring">
<!-- You can use Spring XML syntax to define the routes here using the <route> element -->
<route>
<description>Example Camel Route</description>
<from uri="activemq:example.A"/>
<from uri="file://tmp/a?delete=true"/>
<to uri="file://tmp/b?overruleFile=copy-of-${file:name}"/>
<to uri="activemq:example.B"/>
</route>
</camelContext>
Update with working solution for single file:
<camelContext id="camel" xmlns="http://camel.apache.org/schema/spring">
<!-- You can use Spring XML syntax to define the routes here using the <route> element -->
<route>
<description>Example Camel Route</description>
<from uri="activemq:example.A"/>
<pollEnrich>
<constant>file:///tmp/a?fileName=file1</constant>
</pollEnrich>
<log message="file content ${body}"/>
<to uri="activemq:example.B"/>
</route>
</camelContext>
You need to use Content Enrichers for this. This is exactly what you are looking for.
<route>
<from uri="activemq:example.A"/>
<pollEnrich>
<constant>file://tmp/a?delete=true</constant>
</pollEnrich>
<to uri="activemq:example.B"/>
</route>
Please be aware that for camel version 2.15 or older
pollEnrich does not access any data from the current Exchange which
means when polling it cannot use any of the existing headers you may
have set on the Exchange. For example you cannot set a filename in the
Exchange.FILE_NAME header and use pollEnrich to consume only that
file. For that you must set the filename in the endpoint URI.

How to create a timer based camel polling route?

i created a route that is supposed to read from an OPC-UA endpoint. The read operation should be performed every second, based on a timer. Every example i found shows that the route can only have one from item. My route looks like this:
<camelContext xmlns="http://camel.apache.org/schema/blueprint">
<route id="opctorest">
<from uri="timer://simpleTimer?period=1000"/>
<log message="Triggered Route: opctorest: Sensorreading body: ${body}"/>
<to uri="milo-client:tcp://0.0.0.0:4840/freeopcua/server?nodeId=2&namespaceUri=http://examples.freeopcua.github.io"/>
<convertBodyTo type="java.lang.String"/>
<to uri="stream:out"/>
</route>
</camelContext>
When i deploy the route, it gets called every second, but it writes to the endpoint, since the call is declared in a to element. How can i turn this into a read? I could not find a solution so far. Thanks!
Use the .enrich() to turn it into a read when you want to read in the middle of a route.
http://camel.apache.org/content-enricher.html
For your example something similar to (not tested):
<camelContext xmlns="http://camel.apache.org/schema/blueprint">
<route id="opctorest">
<from uri="timer://simpleTimer?period=1000"/>
<log message="Triggered Route: opctorest: Sensorreading body: ${body}"/>
<enrich uri="milo-client:tcp://0.0.0.0:4840/freeopcua/server?nodeId=2&namespaceUri=http://examples.freeopcua.github.io"/>
<convertBodyTo type="java.lang.String"/>
<to uri="stream:out"/>
</route>
</camelContext>

How to call URL from Apache Camel in blueprint and return the data to a text file?

I am using Apache Camel blueprints, my route is triggered from a URL at port 8081 on localhost. This route generates a file but the problem is the file is a binary file without the HTML showing.
I then navigate my browser to http://localhost:8081/foo which triggers the URL.
What is it that I don't understand that is causing it to output a binary file rather than a text file? I guess that I must transform the body somehow?
<route id="url1">
<from uri="netty4-http:http://0.0.0.0:8081/foo" />
<to uri="http://www.google.com/?bridgeEndpoint=true" />
<to uri="file:/test"/>
</route>
Update: I think the problem is that the content coming back from www.google.com is gzip. When I look at the bridgeEndpoint parameter in the documentation it mentions something about gzip... now I am not sure, as I tried it on another website and it still doesn't work.
This line in my log might be relevant.
writing body: DefaultFullHttpResponse(decodeResult: success,
version: HTTP/1.1, content: UnpooledUnsafeDirectByteBuf(ridx: 0, widx: 0, cap: 0))
Update: I discover if I do:
<from uri="timer:secondfoo?period=20s" />
Replacing the from, then it works. Hmm... Something flowing from the netty4-http causes problem.
Update: I found something which works! Obsession pays off.
<route id="url1">
<from uri="netty-http:http://0.0.0.0:8081/foo" />
<removeHeaders pattern="*" />
<setBody>
<simple></simple>
</setBody>
<setHeader headerName="CamelHttpMethod">
<constant>GET</constant>
</setHeader>
<to uri="http://www.google.com/?bridgeEndpoint=true" />
<to uri="file:/test"/>
</route>
You can convert the message to a String type then its text based
<route id="url1">
<from uri="netty4-http:http://0.0.0.0:8081/foo" />
<to uri="http://www.google.com/?bridgeEndpoint=true" />
<convertBodyTo type="String"/>
<to uri="file:/test"/>
</route>

Apache Camel: Send empty body ws

How can i call a SOAP web service with an empty message body using Apache Camel?
For example, the final endpoint on a route would be the invocation of a method on my proxy that takes 0 arguments.
EDIT:
example xml configuration:
<route id="someRoute">
<from uri="ref:activemq-queue"/>
<setHeader headerName="operationName">
<constant>invoke</constant>
</setHeader>
<to uri="cxf:bean:someWS"/>
</route>
...
<cxf:cxfEndpoint id="someWS" address="${ws.address}"
serviceClass="com.example.ws.SomeWS"
The problem is that the method 'invoke' on the WS takes 0 arguments, and an exception is thrown stating that 1 argument is being received. Is there a way for me to specify to ignore this received input?
You can set the message body to be null, if the invocation just take 0 argument. null simple expression is added since camel 2.12.3.
<route id="someRoute">
<from uri="ref:activemq-queue"/>
<setBody>
<simple>null</simple>
</setBody>
<setHeader headerName="operationName">
<constant>invoke</constant>
</setHeader>
<to uri="cxf:bean:someWS"/>
</route>
I also needed to set an empty body to Apache Camel xml and the solution below worked for me.
<setBody id="set-empty-body">
<constant/>
</setBody>
Hope this helps to whoever need it.
The xml configuration will fail if the content of the body is not with the correct type of the class required by the method of your bean. By default, it could be an Object and not a String. When the method recieves the body in an incorrect format, it would process a null value, instead of the body of the route. To solve this problem, you will need to convert the body into the expected class of the method of your bean. For example, if the method's argument of the bean is a String, then you could do something like:
<route id="someRoute">
<from uri="ref:activemq-queue"/>
<setHeader headerName="operationName">
<constant>invoke</constant>
</setHeader>
<convertBodyTo type="String"/>
<to uri="cxf:bean:someWS"/>
</route>
For more information about body conversion, you can check the docs: https://camel.apache.org/components/3.14.x/eips/convertBodyTo-eip.html

Resources