DZone
Integration Zone
Thanks for visiting DZone today,
Edit Profile
  • Manage Email Subscriptions
  • How to Post to DZone
  • Article Submission Guidelines
Sign Out View Profile
  • Post an Article
  • Manage My Drafts
Over 2 million developers have joined DZone.
Log In / Join
  • Refcardz
  • Trend Reports
  • Webinars
  • Zones
  • |
    • Agile
    • AI
    • Big Data
    • Cloud
    • Database
    • DevOps
    • Integration
    • IoT
    • Java
    • Microservices
    • Open Source
    • Performance
    • Security
    • Web Dev
DZone > Integration Zone > Mule 4 DataWeave Functions: Part 1

Mule 4 DataWeave Functions: Part 1

Let's take a look at this tutorial, which gives an explanation on how to import modules by adding the import directive to the head of the DataWeave script.

Murali Thuraka user avatar by
Murali Thuraka
·
Aug. 06, 18 · Integration Zone · Tutorial
Like (9)
Save
Tweet
36.27K Views

Join the DZone community and get the full member experience.

Join For Free

In DataWeave 2.0, functions are categorized into different modules:

  1. Core (dw::Core)
  2. Arrays (dw::core::Arrays)
  3. Binaries (dw::core::Binaries)
  4. Encryption (dw::Crypto)
  5. Diff (dw::util::Diff)
  6. Objects (dw::core::Objects)
  7. Runtime (dw::Runtime)
  8. Strings (dw::core::Strings)
  9. System (dw::System)
  10. URL (dw::core::URL)

Functions defined in Core (dw::Core) module are imported automatically into your DataWeave scripts. To use other modules, we need to import them by adding the import directive to the head of DataWeave script, for example:

import dw::core::Strings
import dasherize, underscore from dw::core::Strings
import * from dw::core::Strings

Sample Payload:

{
"firstName" : "Murali",
"lastName" : "Krishna",
"age" : "26",
“age” : ”26”
}

1. Core (dw::Core)

Below are the DataWeave 2 core functions:

++ , --, abs, avg, ceil, contains, daysBetween, distinctBy, endsWith, filter, IsBlank, joinBy, min, max, etc.

  • result : [0, 1, 2] ++ ["a", "b", "c"] will gives us “result” : “[0, 1, 2, "a", "b", "c"]”

  • result : [0, 1, 1, 2] -- [1,2] will gives us “result” : “[0]”

  • result : abs(-20) will gives us “result” : 20

  • average : avg([1, 1000]) will gives us “average” : 500.5

  • value : ceil(1.5) will gives us “value” : 2

  • result : payload contains “Krish” will gives us “result” : true

  • days: daysBetween("2016-10-01T23:57:59-03:00", "2017-10-01T23:57:59-03:00") will gives us "days": 365

  • age : payload distinctBy $ will gives us:

{
    "firstName" : "Murali",
    "lastName" : "Krishna",
    “age” : ”26”
}
  • a: "Murali" endsWith "li" will gives us “a” : true

  • a: [1, 2, 3, 4, 5] filter($ > 2) will gives us “a” : [3,4,5]

  • empty: isBlank("") will gives us “empty” : true

  • aa: ["a","b","c"] joinBy "-" will gives us “a” : “a-b-c”

  • a: min([1, 1000]) will gives us “a” : 1

  • a: max([1, 1000]) will gives us “a” : 1000

2. Arrays (dw::core::Arrays)

Arrays related functions in DataWeave are:

  • countBy, divideBy, every, some, sumBy

  • [1, 2, 3] countBy (($ mod 2) == 0) will gives us 1

  • [1,2,3,4,5] dw::core::Arrays::divideBy 2 will gives us:

[
  [
    1,
    2
  ],
  [
    3,
    4
  ],
  [
    5
  ]
]
  • [1,2,3,4] dw::core::Arrays::every ($ == 1) will gives us “false”

  • [1,2,3,4] dw::core::Arrays::some ($ == 1) will gives us “true”

  • [ { a: 1 }, { a: 2 }, { a: 3 } ] sumBy $.a will gives us “6”

3. Binaries (dw::core::Binaries)

Binary functions in DataWeave-2 are:

  • fromBase64, fromHex, toBase64, toHex

  • toBase64(fromBase64(12463730)) will gives us “12463730”

  • { "binary": fromHex('4D756C65')} will gives us “binary” : “Mule”

  • { "hex" : toHex('Mule') } will gives us “hex” : “4D756C65”

4. Encryption (dw::Crypto)

Encryption functions in Dataweave – 2 are:

  • HMACBinary, HMACWith, MD5, SHA1, hashWith

  • { "HMAC": Crypto::HMACBinary(("aa" as Binary), ("aa" as Binary)) } will gives us :

  • "HMAC": "\u0007£š±]\u00adÛ\u0006‰\u0006Ôsv:ý\u000b\u0016çÜð"

  • Crypto::MD5("asd" as Binary) will gives us “7815696ecbf1c96e6894b779456d330e”

  • Crypto::SHA1("dsasd" as Binary) will gives us “2fa183839c954e6366c206367c9be5864e4f4a65”

5. Diff (dw::util::Diff)

It calculates the difference between two values and returns list of differences.

DataWeave Script:

%dw 2.0
import * from dw::util::Diff
output application/json
var a = { age: "Test" }
var b = { age: "Test2" }
---
 a diff b

Output:

{
  "matches": false,
  "diffs": [
    {
      "expected": "\"Test\"",
      "actual": "\"Test2\"",
      "path": "(root).age"
    }
 ]
}

Note:

We will proceed with the rest of the functions in the Mule 4 DataWeave Functions: Part 2 article.

Payload (computing) Diff Filter (software) MOD (file format) Strings Directive (programming) Object (computer science)

Opinions expressed by DZone contributors are their own.

Popular on DZone

  • Observability Tools Help Catch Application Failures — But Automating the Observer Is Becoming Crucial
  • API Security Weekly: Issue 171
  • Everything You Need to Know About Web Pentesting: A Complete Guide
  • 5 Options for Deploying Microservices

Comments

Integration Partner Resources

X

ABOUT US

  • About DZone
  • Send feedback
  • Careers
  • Sitemap

ADVERTISE

  • Advertise with DZone

CONTRIBUTE ON DZONE

  • Article Submission Guidelines
  • MVB Program
  • Become a Contributor
  • Visit the Writers' Zone

LEGAL

  • Terms of Service
  • Privacy Policy

CONTACT US

  • 600 Park Offices Drive
  • Suite 300
  • Durham, NC 27709
  • support@dzone.com
  • +1 (919) 678-0300

Let's be friends:

DZone.com is powered by 

AnswerHub logo