In mule flow I need to compare the last two params from an input string message
2012-04-30,2012-05-30,1,5
And if param1(1) <= param2(5), I need perform jms:outbound-endpoint.
Is there a standard choice element to do it? Could you please provide example.
While using mule 3.2.x your best option is to use the groovy evaluator and use a choice router that look like the following
<when expression="#[groovy:payload.split(',')[2] <= payload.split(',')[3] ]">
<processor-chain>
<jms:outbound-endpoint queue="out" doc:name="JMS"/>
</processor-chain>
</when>
Otherwise if you are willing to upgrade to Mule 3.3.0 you can take advantage of the new Mule Expression Language that allows to do the same without the need of the groovy operator
you can also use splitter and split on the basis of ',' and then have the compare logic for the params
You need not use Groovy for this. You can directly apply the split() function on payload.
<when expression="#[payload.split(',')[2]<=payload.split(',')[3]]">
<processor-chain doc:name="Processor Chain">
<jms:outbound-endpoint queue="data" connector-ref="Active_MQ"doc:name="JMS"/>
</processor-chain>
</when>
Apart from expression filter you can also use choice flow control. Capture the 2 values to be compared in a flowvars and use below expression in when condition of choice flow control.
[flowVars.param1 <= flowVars.param1]
Giving below the link for more information.
https://docs.mulesoft.com/mule-user-guide/v/3.7/choice-flow-control-reference
you can take advantage of the new Mule Expression Language that allows to do the same without the need of the groovy operator
Related
I'm trying to connect to SQL Database with some configuration. But based on the input from the API we are supposed to hit different DB.
As of now, we have the code as
<choice doc:name="Check myFlag">
<when expression="#[flowVars.myFlag == 'true']">
<db:stored-procedure config-ref="Database_Configuration_1" doc:name="DB_config_1">
<db:dynamic-query><![CDATA[#[flowVars.callSPName]]]></db:dynamic-query>
</db:stored-procedure>
</when>
<otherwise>
<db:stored-procedure config-ref="Database_Configuration_2" doc:name="DB_config_2">
<db:dynamic-query><![CDATA[#[flowVars.callSPName]]]></db:dynamic-query>
</db:stored-procedure>
</otherwise>
</choice>
Instead of repeating <db:stored-procedure../> twice, is there a way where I can set a flow var with the DB config reference and use it?
Something like,
<db:stored-procedure config-ref="#[flowvars.db_config]" doc:name="DB_config_2">
<db:dynamic-query><![CDATA[#[flowVars.callSPName]]]></db:dynamic-query>
</db:stored-procedure>
In Mule 3, no. config-ref's are evaluated at application startup, not runtime.
In Mule 4 this is possible using Dynamic Configurations: https://docs.mulesoft.com/mule-sdk/1.1/static-dynamic-configs
Potential Mule 3 solutions documented here: https://help.mulesoft.com/s/article/How-to-configure-connector-with-dynamic-parameters
Put the DB call inside a sub-flow and call it from the rest of the flows with a <flow-ref>.
How do check if the variable exist in Mule 3.2?
How create or replace a variable?
My Flow Exception is
<choice doc:name="Choice">
<when expression="#[myVar==null]">
<processor-chain>
<set-variable variableName="myVar" value="value1" doc:name="myVar"/>
</processor-chain>
</when>
<otherwise>
<processor-chain>
<set-variable variableName="myVar" value="#[variable:myVar]" doc:name="myVar"/>
</processor-chain>
</otherwise>
</choice>
"myVar==null" does not work
if the variable is an invocation variable please try
flowVars['myVar'] == null
Worst case scenario you could do:
message.getProperty('myVar', org.mule.api.transport.PropertyScope.INVOCATION).
Please notice the scope is an enum so you should provide the canonical in a MEL expression.
HTH
You can use this MEL to print in log or use in Choice component
#[message.invocationProperties('myVar')] == null
There is a component "Message Property" which will help you remove or replace or create Mule message properties. You should use that to perform your operation.
To best find it use keyword "propert" in the search of pallets in the Mule studio and explore the various components there to suit your needs.
I have a requirement where I run xPath evaluator against xml payload in mule flow. This xPath evaluator can return single or multiple values. I need to store these values in flow variable and use somewhere later in the flow. Can someone help me implementing this changes?
Appreciate your help on this.
Thanks
For extracting values from an XML document, use the XPath extractor.
<mulexml:xpath-extractor-transformer expression="/a:my/b:xpath/text()"/>
You can also use Mule Expression Language to create dynamic XPath expressions:
<expression-transformer mimeType="text/xml" evaluator="xpath" expression="//school/day[#date= #[function:datestamp:yyyy-MM-dd] ]/name
"/>
However this can get somewhat messy for complicated expressions, so I have created my own dynamic XPath transformer:
<dx:dxpath expression="/b:team[name = $teamName]/b:player[b:name = $playerName]/b:goals/text()">
<dx:variable key="playerName" value="#[header:invocation:playerName]"/>
<dx:variable key="teamName" value="#[header:invocation:teamName]"/>
<!-- unlimited number of variables -->
</dx:dxpath>
which is somewhat more easy on the eyes.
Then Wrap your flow with an ericher:
<enricher target="#[variable:myData]">
<processor-chain>
<!-- your flow here -->
</processor-chain>
</enricher>
What is the best way to perform a string manipulation. I wish to perform a substring on a email address to extract the domain detail and populate this to a variable.
a java transformer is a possibilty, but i was hoping if i could use a message enricher with a expression to perform this operation.
pardon me but i am still a greenhorn on Mule.
here is the excerpt from my mule flow which is failing with error cannot resolve method string length.
<enricher target="#[flowVars['FromAddressDomain']]" doc:name="Message Enricher">
<expression-transformer expression="#[ payload.fromAddr.substring(payload.fromAddr.lastIndexOf('#')+ 1,payload.fromAddr.lenth())]" doc:name="Expression"></expression-transformer>
</enricher>
Simply use:
<set-variable variableName="FromAddressDomain"
value="#[org.mule.util.StringUtils.substringAfter(payload.fromAddr, '#')]" />
You can use dataweave transform on payload and use the operator splitby and spilt on # character. Please take a look at below link for more information on splitby operator
https://docs.mulesoft.com/mule-user-guide/v/3.9/dataweave-operators#split-by
I'm trying to learn Mule ESB but get problems with example projects. Why are these lines
underlined red and not represented in the Message flow?
<expression-transformer name="returnAttachments">
<return-argument evaluator="attachments-list" expression="*.txt,*.ozb,*.xml" optional="false"/>
</expression-transformer>
I've cut and pasted these lines from mulesoft.org as part of a sample project.
#genjosanzo is right, the MEL equivalent would be:
<expression-transformer
expression="#[($.value in message.inboundAttachments.entrySet() if $.key ~= '(.*\\.txt|.*\\.ozb|.*\\.xml)')]" />
Mule studio has problem rendering nested elements (bug reported here)
Instead you can use the compact version and replace it with the following:
<expression-transformer expression="#[attachments-list:*.txt,*.ozb,*.xml]" doc:name="Expression" />
On a side note ever since mule 3.3.0 the new mule expression languages and it is recommended to rely on it whenever possible.