10 Quick Dataweave Functions
This quick reference collects many Dataweave functions for MuleSoft in one place, like reversing strings and flattening and trimming a payload.
Since Dataweave is new in MuleSoft, it's hard to identify how to do some basic functions like substring reversing a string. This guide will provide all the functions in one place, which saves developers time. Below is the JSON I am using as a sample payload.
{
"firstName":"satheesh",
"lastName":"Kumar",
"age":"26",
"Amount":10.5
}1. Substring
Most of us need to use substring somewhere in Dataweave, and it's very simple.We have to use the range operator the range can be mentioned as in array.
firstName: payload.firstName[0..3] will give you "firstName": "sath."
2. Reverse a String
Reversing a string is made very easy in Dataweave, so when you have a palindrome or not program next time, you don't need to use Java. You can use it directly in Dataweave.
firstName: payload.firstName[-1..0] will give you "firstName": "hseehtas."
3. Replace
To replace a string with another, the replace function is used.
firstName: (payload.firstName replace "s" with "new") will give you "firstName": "newatheenewh."
4. Identify the Size of the String
To identify the size of any value, the size of operator is used. It's not only for strings- it's for measuring arrays or lists, too.
sizeOfFirstName: sizeOf payload.firstName will give you "sizeOfFirstName": 8.
5. Concat
Concatenation is made very easy in Dataweave; it can be done by just using + operator .
Name: payload.firstName ++ " " ++ payload.lastName will give you "Name": "satheesh Kumar."
6. Trim
Trimming unwanted spaces is always required in integrations.
When the first name is " satheesh," use Name: trim payload.firstName and it will give you "Name": "satheesh."
7. Other String Operations
I don't need to explain this as the example says everything.
| Input | Function | Sample | Result |
| satheesh | capitalize | Name: capitalize payload.firstName |
Name:Satheesh |
| satheesh_mule_developer | camelize | Name: camelize payload.firstName |
satheeshMuleDeveloper |
| monday tuesday | dasherize | Name: dasherize payload.firstName |
monday-tuesday |
| child | pluralize |
Name: pluralize payload.firstName |
children |
| cars | singularize | Name: singularize payload.firstName |
car |
| SAtheesh | lower | Name: singularize payload.firstName |
satheesh |
| SaTheesh | upper | Name: singularize payload.firstName |
SATHEESH |
8. Flatten
When you have a multiple array list from multiple sources as shown below, Flatten will be very handy.
[{
"firstName":"cars",
"lastName":"Kumar",
"age":"26",
"Amount":10.5
}],
[{
"firstName":"cars",
"lastName":"Kumar",
"age":"26",
"Amount":10.5
}] flatten.payload will give you
[{
"firstName":"cars",
"lastName":"Kumar",
"age":"26",
"Amount":10.5
},
{
"firstName":"cars",
"lastName":"Kumar",
"age":"26",
"Amount":10.5
}]9. Floor and Ceil
The Floor function will round down the decimal value into an integer and Ceil will round up the decimal value into an intenger.
"age":26.5
age: floor payload.age will give you 26.
age: ceil payload.age will give you 27.
10. Now
The Now function will give you the current date and time.
currentTime: now will give you "currentTime": "2016-10-20T17:15:06.196Z."
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