Is there a way in mule to extract parent flow message in sub/synchronous flow after sub message source has generated its message and modify it.Sub flow is having its own message source.
You can always get the message of parent flow in sub flow ..
Now extracting a message depends on its data type ...
For example if the payload type is xml and you need to extract particular value of a node, you can use XPATH...
Similarly for JSON payload there is different techniques of extracting it..
And now if you want the entire payload of parent flow and not just part of it, then you can always use #[message.payload] expression in subflow
Related
We are migrating from Mule 3 to Mule 4 and in one of our functionalities we need to publish messages to a topic and downstream another mule component is consuming from the queue which is bridged to the topic.
Nothing special here .
To ensure we are able to trace the flow via logs we were sending a 'TrackingId' attribute while publishing messages to the topic ( Mule 3 )
message.setOutboundProperty("XYZ_TrackingID", flowVars['idFromUI']);
return payload;
However when I try the same in Mule 4 we get the following exception :
ERROR 2020-12-20 10:09:12,214 [[MuleRuntime].cpuIntensive.14: [mycomponent].my_Flow.CPU_INTENSIVE
#66024695] org.mule.runtime.core.internal.exception.OnErrorPropagateHandler:
Message : groovy.lang.MissingMethodException: No signature of method:
org.mule.runtime.api.el.BindingContextUtils$MessageWrapper.setOutboundProperty() is applicable for
argument types: (java.lang.String, org.mule.weave.v2.el.ByteArrayBasedCursorStream) values:
[XYZ_TrackingID, "1234567"].\nError type : (set debug level logging or '-
Dmule.verbose.exceptions=true' for
everything)\n********************************************************************************
Checked internet and it seems in Mule4 setting outbound properties is removed as per here
So how do I achieve the same in Mule 4 ?
Don't even try to do that for several reasons. For one message structure is different, so output properties doesn't exist anymore and that method doesn't even exists. On the other hand, in Mule 4 components like the Groovy component can only return a value and cannot change the event. They can not decide to what that value is going to be assigned. You can set the target in the configuration (payload or a variable) and not change the attributes. Note that variables in Mule 4 are referenced by var., not by flowVars. like in Mule 3 (ie vars.idFromUI).
There is a simpler way to set message properties in the Mule 4 JMS connector. Use the properties element and pass it an object with the properties.
For example it could be something like this:
<jms:publish config-ref="JMS_config" destination="${bridgeDestination}" destinationType="TOPIC">
<jms:message>
<jms:body>#["bridged_" ++ payload]</jms:body>
<jms:properties>#[{
XYZ_TrackingID: vars.idFromUI
}]</jms:properties>
</jms:message>
</jms:publish>
It is in the documentation: https://docs.mulesoft.com/jms-connector/1.0/jms-publish#setting-user-properties. I adapted my example from there.
I am not sure if Correlation Id serves the purpose of a tracking ID for your scenario. But you can pass a CID as below. It's there in the mule documentation.
https://docs.mulesoft.com/jms-connector/1.7/jms-publish
<jms:publish config-ref="JMS_config" sendCorrelationId="ALWAYS" destination="#[attributes.headers.replyTo.destination]">
<jms:message correlationId="#[attributes.headers.correlationId]"/>
</jms:publish>
If your priority is to customise the Tracking ID you want to publish, then try passing below format. The key names may differ as per your use case.
<jms:publish config-ref="JMS_config" destination="${bridgeDestination}" destinationType="TOPIC">
<jms:message>
<jms:body>#["bridged_" ++ payload]</jms:body>
<jms:properties>#[{
AUTH_TYPE: 'jwt',
AUTH_TOKEN: attributes.queryParams.token
}]</jms:properties>
</jms:message>
</jms:publish>
In the above the expression attributes.queryParams.token is basically trying to access a token query parameters which is passed to JMS as a property AUTH_TOKEN key-name , consumed by the API through a HTTP Listener or Requestor earlier.
However, attributes.headers.correlationId is a header. Both queryParams and headers are part of attributes in Mule 4.
I am getting some attributes in an API but all getting lost after an HTTP request connector in mule4.
why is it happening?
Look in the connector's configuration properties -> advanced tab for the connector configuration (in this case the HTTP connector's "request" operation) and you'll find a target variable and target value. If you fill in the target with a name - this does an enrichment to avoid overwriting the Mule message. If you leave it blank (the default) it will save the message (attributes, payload) over the top of the existing one - which is what you're seeing now. This mirrors the old mule 3 functionality, but sometimes you want it to leave what you have there alone.
So for the target value you get to pick exactly what gets saved.. If you want just payload: put that in. If you want both payload and attributes - I'd use "message" as that will mean you get both payload and attributes saved in the variable. Of course you may not want as much saved, so feel free to put in whatever dataweave expression you like - so you could even create something with bits from anywhere like:
{
statusCode: attributes.statusCode,
headers: attributes.headers,
payload: payload
}
A connector operation may replace the attributes with those of the operation. If you need to preserve the previous attributes you need to save them to a variable.
This is a default behaviour of MuleSoft. Whenever request crosses to transport barrier it losses existing attributes. You need to preserve attribute before HTTP Request.
Payload in muleflow is getting converted in com.mulesoft.weave.reader.DefaultSeekableStream from org.glassfish.grizzly.utils.BufferInputStream. I am not sure why and due to this the subsequent activities (dw transformer) is failed. Anyone have any idea what could be the reason and how to overcome this.
The payload is pretty simple and I am trying to use two transformation activity, In first activity I parse the payload and create a flowVariable and in second transformation is to add values in payload. However, after first transformation the payload is changed to DefaultSeekableStream.
Thanks,
Abhi
Error message:
Im new on Mule ESB and i have the next problem. I use connector "Collection Splitter" to separate a list of orders (books) to other things. When i do the checks i go back to join the books on the order with connector "Collection Agreggator". What i want is save the information of the payload in that moment in a session variable. The system dont do that. I think is posible because the type saves on the payload is "CopyOnWriteArrayList" type and i dont now if is posible save this type of list in a session variable.
Someone can be help me please?
Thanks!
You can also use a set-session-variable transformer. Set the name is something of your choosing and set the value to be #[payload]. That you will maintain both your payload and have a new session variable. However be very careful when using session variables, since these are serialized when sending a Mule message over a transport. If possible, try to use flow variables.
use the message enricher scope to achieve the same.
define the required component inside the message enricher scope.
in the enricher scope specify source as payload and the target as session variable.
try and let me know the status.
In my flow I have a soap client calling a service. Since we are using 3 different operations from the service I'd like to dynamically fill in the "Operation" field under "Client Attributes" in Mule soap component. The way I have it working right now is:
start flow -> message transformation -> choice flow control (based on the message type)
choice 1. sub flow A -> soap client with operation A
choice 2. sub flow B -> soap client with operation B
choice 3. sub flow C -> soap client with operation C
What I would like is to dynamically in runtime set the "Operation" field based on the message and not have three different subflows.
start flow -> message transformation -> set the operation field -> soap client with the correct operation
Is that possible? Using Mule CE 3.3.1. Thanks in advance.
To achieve your goal:
Remove the operation attribute from the cxf:jaxws-client element,
Add set the operation as an outbound message property before the cxf:jaxws-client element with:
<set-property propertyName="operation" value="#[...]" />
where #[...] represents a MEL expression that extracts the operation name from the message.