Still learning Mulesoft's Anypoint Studio... I am confused as how will I be able to access raw JSON POST data via the HTTP Listener then use the Choice flow control to execute conditions based on a value from a given JSON index. Anyone can show/tell me how to do this?
The JSON HTTP body will automatically become the payload of your message in Mule probably represented as Stream.
Just for demo purposes, try logging the payload after your http:listener using:
<object-to-string-transformer />
<logger level="INFO" message="#[payload]" />
There best way to query JSON is to transform it to a Map suing the JSON module transformers.
<json:json-to-object-transformer returnClass="java.util.HashMap" />
And then query it using MEL like standard MVEL or Java syntax.
For a JSON document like: {"person" : {"name" : "bob"}}
<logger message="#[payload.person.name]" level="INFO" />
You can use these expressions in your choic router also:
<choice>
<when expression="#[payload.person.name == 'bob']">
do something ...
</when>
</choice>
Related
I need to concatenate text with json payload in logger component. I have tried below ways but no luck
<logger level="INFO" doc:name="Logger" doc:id="38de876a-a64f-4d83-86a1-ef4cbbda167c" message="#['payload is:' + payload]"/>
Even i don't see any transformers like 'object to string converter' in mule 3.
Please suggest syntax for mule 4
Try separating the text from your dataweave
i.e.
<logger level="INFO" doc:name="Logger" mesage="Payload is: #[payload]" doc:id="38de876a-a64f-4d83-86a1-ef4cbbda167c" />
All the various transformers were removed in Mule 4 due to the payload always being "accessible". That is, regardless of the payload type (XML, JSON, Java, CSV...) you can access fields through payload.{fieldname}. In Mule 3.x the payload had to be coerced to a Java object to allow that. You can explicitly set the output type of any dataweave expression, so you can also try:
mesage="Payload is: #[output application/java --- payload]"
It is working with below syntax
<logger level="INFO" doc:name="Logger" doc:id="38de876a-a64f-4d83-86a1-ef4cbbda167c" message="#['payload is:' ++ payload]"/>
I had the same issue and the below worked for me...
<logger level="INFO" doc:name="Logger" doc:id="35d4566e-02ba-495a-bd40-c30aa5a90413" message="#['Get Accounts Response Paylaod : #[payload]']"/>
I am using the below code to convert the input payload string to json in mule. The below code sometimes working and sometimes not. its not working on standalone and working on studio. Not able to nail down the exact cause for it. but based on the loggers that i see that the property value is coming null after the expression statement. i am suspecting this could be with the jar that's getting used here. i am still digging further on it.
<logger message="input: #[payload]" level="INFO" doc:name="Logger"/>
<set-payload value="#[payload.'data']" mimeType="application/json" doc:name="Set Payload" encoding="ISO-8859-2"/>
<logger message="createConnection: #[payload]" level="INFO" doc:name="Logger"/>
<expression-component doc:name="Expression"><![CDATA[String input = payload;
payload = new org.json.JSONObject(input);
]]></expression-component>
<logger message="before json to object: #[payload.con_id] #[payload.'con_id']" level="INFO" doc:name="Logger"/>
<json:json-to-object-transformer returnClass="java.util.HashMap" doc:name="JSON to Object"/>
Input JSON:
data: {"name":"QA_tst2","description":"tst","con_id":10,"con_connection_id":null,
"verticalParam":[{"param_value":"abc","param_name":"Host"},{"param_value":"21","param_name":"Port"}],"CON_CATEGORY_NAME":"File"}
I don't think that notation will work for JSONObject, try using
payload.get('con_id')
as per the javadoc: https://stleary.github.io/JSON-java/org/json/JSONObject.html.
The reason this won't work with the notation you have tried, is that Mule supports that notation for Maps, and org.json.JSONObject does not implement java.util.Map. You could try using javax.json.JSONObject instead, which will support that notation.
I have figured out the current issue. if there is any logger added to fetch the properties from the payload right after the expression component then its screwing up further. if you just remove the logger that was added after the expression component then after json to object conversion, i am able to fetch the values. that solves the current issue. but i would like to understand the difference between fetching the properties #[payload.con_id] vs #[payload.'con_id']. i can start a separate conversation for the same.
I want to perform some string operation on MEL I have following expression in MEL
<logger message="#[json:xy/PID/xy.3/AC]" level="INFO" doc:name="Logger"/>
OUTPUT IS
19901026000000
I want to extract 1st 4 digit then 6,7 digit .
How can I do this ??
Thanks
What about trying it in two steps?
<set-variable variableName="result" value="#[json:ADT_A01/PID/PID.3/CX.1]" />
<set-variable variableName="result" value="#[result.substring(0,4)]#[result.substring(5,7)]" />
As noted in the comments in #Ryan Hoegg answer, the JSON expression evaluator has been deprecated since Mule 3.3 and hence the best way to do this would be to use a json to object transformer
<json:json-to-object-transformer doc:name="JSON to Object" returnClass="java.util.HashMap"/>
and then use conventional MEL to traverse the Map
JsonPath expression are depreciated for now and you will even not get enough document on it for doing ..
So, currently you need to use either :- <json:json-to-object-transformer returnClass="java.lang.Object" doc:name="JSON to Object" />
or <json:json-to-object-transformer returnClass="java.util.HashMap" doc:name="JSON to Object" />
or even <json:json-to-object-transformer returnClass="java.util.List" doc:name="JSON to Object" /> to extract data from JSON depending on the JSON data
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"/>
I have a flow where I want to evealuate an expression on the smtp subject attribute but always get mvel parse expression though the logger give me the right values.
<json:object-to-json-transformer doc:name="Object to JSON"/>
<logger message="MYRequestPayloadID #[json:RequestPayloadID] #[json:ResponseStatusCd]" level="DEBUG" doc:name="Logger"/>
<smtp:outbound-endpoint host="${mail.host}" to="${mail.to}" from="${mail.from}" subject="Error Response for PayloadID #[json:RequestPayloadID], Status #[json:ResponseStatusCd]" responseTimeout="10000" doc:name="SMTP />
I am not sure why in the subject #[json:RequestPayloadID] and #[json:ResponseStatusCd] evaluation fail though I get the data back in the logger . Thanks.
Expressions are not supported everywhere in Mule (alas): this is one place where it isn't.
You have to use message properties to set the subject dynamically:
<set-property propertyName="subject"
value="Error Response for PayloadID #[json:RequestPayloadID], Status #[json:ResponseStatusCd]" />
FTR json: is the old expression style, nowadays you should be using MEL instead: http://www.mulesoft.org/documentation/display/current/Mule+Expression+Language+Tips#MuleExpressionLanguageTips-JSONProcessing