To assign multiple values to a set payload transformer in mule - mule

In order to set multiple values to a set payload transformer in mule we use
<set-payload value="#[{1000,1,1,1}]" doc:name="Set Payload"/>
can we assign multiple flow variables to a set payload transformer
<set-payload value="#[{flowVars['principal'],flowVars['years'],flowVars['rate'],flowVars['appid']}]" doc:name="Set Payload"/>
Or is there any other right way to do it
Thank you in advance

Yes, this will work just fine. Whether you can do something that looks prettier, would be up to your full flow configuration.

You can also use as following :-
<set-payload value="#[flowVars['principal']] #[flowVars['years']] ..." doc:name="Set Payload"/>

Related

Accessing variable inside of forEach in mule

I have two queries
Suppose if I declared two variables inside a forEach like flowVars.ABC and flowVars.DEF, how can I access those 2 variables outside that forEach block?
And each variable has a JSON payload, how can I add those 2 variable's data into single JSON payload?
Can anyone assist me? I unable to access the variables inside of foreach and adding 2 JSON.
This is my sample code
<flow name="test">
<foreach doc:name="For Each">
<scatter-gather doc:name="Scatter-Gather">
<set-variable variableName="ABC" value="#[payload]" mimeType="application/json" doc:name="ABC"/>
<set-variable variableName="DEF" value="#[payload]" mimeType="application/json" doc:name="DEF"/>
</scatter-gather>
</foreach>
<set-payload value="#[flowVars.ABC + flowVars.DEF]" mimeType="application/json" doc:name="adding 2 vars"/>
</flow>
You need to understand how scoping works with foreach. Any variables set inside the foreach scope will NOT be available outside of that scope. However, variables set outside of the foreach scope (e.g. a set-variable before the foreach) will be available inside the foreach scope. This should help you get around your issue. I'm taking out the scatter-gather because it really doesn't serve any purpose in your example:
<flow name="test">
<set-variable variableName="ABC value="#[payload] mimeType="application/json" doc:name="ABC"/>
<set-variable variableName="DEF value="#[payload] mimeType="application/json" doc:name="DEF"/>
<foreach doc:name="For Each">
<set-variable variableName="ABC" value="#[payload]" mimeType="application/json" doc:name="ABC"/>
<set-variable variableName="DEF" value="#[payload]" mimeType="application/json" doc:name="DEF"/>
</foreach>
<set-payload value="#[flowVars.ABC ++ flowVars.DEF]" mimeType="application/json" doc:name="adding 2 vars"/>
</flow>
Beyond this, I'm not sure if your code is a simplification or not, but as it stands now there are a couple things that are questionable:
Why are you using a scatter-gather? If you don't really need to do multiple things asynchronously (like making calls to multiple services), it's just a complication in your code. Setting two vars doesn't qualify, in my opinion.
What is your code supposed to do? From my perspective it looks like you're just setting the payload to a duplicate of the last element in the original payload. If so you could just do this in a transformer:
%dw 2.0
output application/json
---
if (not isEmpty(payload))
payload[-1] ++ payload[-1]
else
[]

How to convert org.glassfish.grizzly.utils.BufferInputStream to JSON in Mule?

On my first steps with Mule I'm writing a basic Http Proxy.
Currently I forward the request to the api server and what I'd like to do is reading the payload that I receive from it before responding to the client.
When I try to log it with #[payload] it prints
org.glassfish.grizzly.utils.BufferInputStream#2306df30
How can I print it properly in JSON format?
The full code:
<flow name="proxy">
<http:listener config-ref="http-lc-0.0.0.0-8081" path="![p['proxy.path']]" parseRequest="false"/>
<http:request config-ref="http-request-config" method="#[message.inboundProperties['http.method']]"
path="#[message.inboundProperties['http.request.path'].substring(message.inboundProperties['http.listener.path'].length()-2)]" parseResponse="false">
<http:request-builder>
<http:query-params expression="#[message.inboundProperties.'http.query.params']"/>
</http:request-builder>
<http:success-status-code-validator values="0..599" />
</http:request>
<logger doc:name="Logger" level="INFO" message="Payload #[payload]"/>
The payload after HTTP request is generally in stream format, ref:- https://docs.mulesoft.com/mule-user-guide/v/3.7/http-request-connector
There are two ways you can get the payload after http:request
1) <object-to-string-transformer doc:name="Object to String"/> after http:request
or
2) using a logger and use MEL expression <logger message="#[message.payloadAs(java.lang.String)]" level="INFO" doc:name="Logger"/>
Try #[message.payloadAs(java.lang.String)] which will log the expected output.
Hope this helps.
The http component will send as InputStream,So use byte array to string transformer after http component.If you just want to print you can use #[message.payloadAs(java.lang.String)] but you wanna do any operation just drag and drop a byte array to string transformer
Simplest way is to just use <object-to-string-transformer doc:name="Object to String"/> after http request component and then place a logger with #[payload].
One way to make sure that you get proper JSON response is to set payload as application/json mimetype.
<set-payload value="#[payload]" mimeType="application/json" doc:name="Set Payload"/>
Add this line after the HTTP Request. Just setting the payload value as #[payload] will convert it to json While converting it to string will just print it as string and not make it Json type.

Return individual values from linkedHashMap in Mule

I have an output from a webservice in Mule that returns a linkedHashMap and I need to get the individual values to be dynamically inserted into a template. The template is used to send email through the SMTP connector. I can get all values using MEL #[payload], but I can't get them one by one. I've tried #[payload.get(0)], #[payload[0]] but they all return null.
The Mule XML looks like this:
<flow name="MW_Flow">
<file:inbound-endpoint path="C:\....\1" connector- ref="File" responseTimeout="10000" doc:name="File" pollingFrequency="60000"/>
<ws:consumer config-ref="File_Read_WS" operation="all3" doc:name="FileRead DBWriter WS"/>
<dw:transform-message metadata:id="6ee92ba8-9f67-40d6-bfa3-3e237da20822" doc:name="Transform Message">
<foreach doc:name="For Each">
<logger message="#[payload]" level="INFO" doc:name="Logger"/>
<parse-template location="C:\.....\Templates\Mail.txt" metadata:id="b7d894eb-465b-47f7-a542-b49fc4fb53d9" doc:name="Parse Template"/>
<logger message="2: #[message.exception] #[message.dataType] #[payload]" level="INFO" doc:name="Logger"/>
</foreach>
</flow>
The template (plain text file) looks a bit like this:
Hello [name].
This is email from [name2]. The following event [event].....
All I get are null values except when using #[payload] which returns the whole row (4 values).
Any help greatly appreciated!
/Johan
If your payload is a Map then payload.get(0) or payload[0] will behave as if you are trying to get a value from map with 0 as key, which I guess doesn't exist in your map.
Try accessing it with name - #[payload.name] or #[payload.name2] or #[payload[name]]

Aggregate data from for-each loop

Scenario - Converting a csv file to json format, taking each json element and making a get request api call. I am doing this in a for-each loop sequence. I am getting a json response (extracting eventId and cost from each). Now I wish to club all these responses together under the main header listings and make a bigger json payload.
For example:
{
"listings": [
{
"eventId":"8993478",
"cost":34
},
{
"eventId":"xxxxxyyyy",
"cost":zz
},
]
}
How would I do this for all iteration entries. I can do it for a single entry(using groovy script).
You could define a variable before the for-each loop as an empty list with:
<set-variable variableName="listings" value="#[[]]" />
Then, on each iteration inside the for-each loop add an element to the previous variable with:
<expression-transformer expression="#[flowVars.listings.add(flowVars.iterationMap)]" />
In the previous code fragment I used the variable flowVars.iterationMap to denote the map generated on each iteration.
Finally, if needed, you can add a set-payload transformer after the for-each loop:
<set-payload value="#[flowVars.listings]" />
HTH, Marcos
You can use the Batch module but you would have to rewrite this logic a little bit different. For example, you will no longer be able to use an aggregation flowVar like Marcos suggested. Instead, you would need to use a fixed size batch:commit block (which would actually be better in many ways, for example you could start sending bulks to the remote API while still processing some of the other records in the background).
...I like Marco's answer and it worked perfectly for my use case.
Simply creating an array in a flow variable and using the add() method on the array in a ForEach scope did the trick.
The OP follow up question was a good one. It prompted me to do an alternate test using the approach suggested. See both of my flows here:
<flow name="sampleAggregatorFlow" doc:description="this is a simple demo that shows how to aggregate results into an accumulator array">
<http:listener config-ref="manage-s3-api-httpListenerConfig" path="/aggregate" allowedMethods="GET" doc:name="HTTP"/>
<set-payload value="#[['red','blue','gold']]" doc:name="Set Payload"/>
<set-variable variableName="accumulator" value="#[[]]" doc:name="accumulator"/>
<foreach doc:name="For Each">
<expression-transformer expression="#[flowVars.accumulator.add(payload)]" doc:name="addEm"/>
</foreach>
<set-payload value="#[flowVars.accumulator]" doc:name="Set Payload"/>
<json:object-to-json-transformer doc:name="Object to JSON"/>
</flow>
<flow name="Copy_of_sampleAggregatorFlow" doc:description="this is a simple demo that shows how to aggregate results into an accumulator array">
<http:listener config-ref="manage-s3-api-httpListenerConfig" path="/aggregate2" allowedMethods="GET" doc:name="Copy_of_HTTP"/>
<set-payload value="#[['red','blue','gold']]" doc:name="Copy_of_Set Payload"/>
<set-variable variableName="accumulator" value="#[new java.util.ArrayList()]" doc:name="Copy_of_accumulator"/>
<foreach doc:name="Copy_of_For Each">
<expression-transformer expression="#[flowVars.accumulator.add(payload)]" doc:name="Copy_of_addEm"/>
</foreach>
<set-payload value="#[flowVars.accumulator]" doc:name="Copy_of_Set Payload"/>
<json:object-to-json-transformer doc:name="Copy_of_Object to JSON"/>
</flow>
Both flows produced the same outcome:
[
"red",
"blue",
"gold"
]
Tests conducted 12/26/2017 with Anypoint Studio 6.4.1 and wth Mule Runtime 3.9

How to Extract the Flow Name and MessageProcessor Name using MEL - MULE ESB

I'm not sure, how can we extract the flow-name and message-processor Name through MEL. For example I have multiple message processor. For logging, i need to extract the flow Name and Message-processor, so that I can find out transaction has crossed this particular flow and its message processor. Is there any simple way to find out. Please guide me. Please find the screenshot below. Here i need to Extract - set payload and its flowName (flow1)
Thanks in advance.
For mule 3.8+ version onwards #[flow.name] don't work.
Use #[mule:context.serviceName] expression in logger or component to extract the name of the flow
I know this post is old but I have been trying to find a way to do this in MEL for error handling emails.
For the flow name you can use #[exception.event.flowConstruct.name]
for the failing message processor you can use #[exception.failingMessageProcessor].
Both of these work in MEL without the need to use an flowVar.
Please note however, that the failing processor does not always come back with a value but comes back with null, I'm not sure why.
You can extract the flow-name with MEL : #[flow.name]
<flow name="name" doc:name="name">
<http:inbound-endpoint address="http://localhost:8090/resources" doc:name="HTTP" />
<logger message="name of flow: #[flow.name]" level="INFO" doc:name="Logger"/>
<set-payload value="name" doc:name="Set Payload"/>
</flow>
or
flowConstruct.getName() in a Message Processor
Two ways to acthive this (from current flow name)
First one is -
<logger message="Current flowName: #[flow.name]" level="INFO" doc:name="Logger"/>
and the second one is -
<logger message="Current flowName: #[context:serviceName]" level="INFO" doc:name="Logger"/>