Script data and Text data

Camunda 7 Topics Discussion & Questions
1

why do we keep Script & Text both in Output Parameters

what is the purpose of Script dataType in Camunda modeller ?

Here is an example:

outputdata

Note that outputVarName is the value of offerprice Script.

2

For me, the script is one of the most used type in input output mappings, because I can create Objects of any kind easily, at least easier than filling maps and lists, and itā€™s much more powerful. These objects can be used by other components without any problem.

Iā€™m not sure if offerprices script is evaluated before beeing assigned to the Text Variable outputVarName, so I never use input or output mapping in this way.

3

My confusion is when we should be using Script type and when Text type ? any example please.

4

A script is a output type with a name because scripts last executed functions are returned. Example in JavaScript if you just wrote 2+2 then that eval would be returned.

A script does not need to return something, so you have options. Think of scripts as a way to manipulate data and preform actions.

5

An example:
Suppose you have to pass the output variable as a calculated map to the rest of the execution.
Output Var Name: ā€œmyMapā€
Output Var Type : ā€œScriptā€
script type: ā€œgroovyā€
body:

return [   
    city: [ name: city_name, country: city_country ],
    products: listProducts1.addAll(listProducts2),
]

This script will save in myMap an map of objects (a list and a map in this case)

You can use this object as you wish in other following scripts/juel expression or java delegates.
For example for an expression :

${myService.processAndSave(myMap)}

or
${myService.saveProduct(myMap.products)}

But this is an example. The possibilities are endless.

6

@Mizar01

You are using ā€œgroovyā€. Do you need to return in grovy script ? I dont know grrovy .I know javascript.

7

Say , I write these ā€¦

Name: outputVar
Type: Script ,
Script Format : Javascript .
Script Type: Inline script

Script
var inData = execution.getVariable(ā€œinputDataā€);
var someOtherVar= JSON.parse(productType);

what will be returned ?

Is it the only the last variable i.e someOtherVar or both ?

You said ā€¦

Does this mean only last executed part i.e someOtherVar will be returned here ?

Please correct me if Iā€™m wrong.

8

@cofactor, You can do a lot of things. As a groovy script, I donā€™t know if it works for others, you can return a variable using ā€˜return varNameā€™ or simply using ā€˜varNameā€™ as the last line of the script.

Like you said, the last line of code will be the returning value, but if you put
varName = ā€œsome Valueā€
this line will return null, because itā€™s an assignment. In groovy this will return the variable itself, so it should work, but I donā€™t guarantee in other languages. You should do something like one of these:

varName = ā€œsome Valueā€
varName
OR
ā€œsome Valueā€
OR
return ā€œsome Valueā€
OR
varName = ā€œsome Valueā€
return varName

You can also return null and set some execution variables (maybe you donā€™t use a script for input mapping without a returning value, but theoretically you can).

1 Like
9

@Mizar01

That was very much helpful.

11

@cofactor

you would do:

var inData = execution.getVariable(ā€œinputDataā€);
var someOtherVar= JSON.parse(productType);
someOtherVar;

Where line 3 is the return final value. But you do not need to do this in every case. often you are wrapping all of your code in ā€œfunctionsā€ and thus you are using execution.setVariable() rather than the final returned value.

1 Like