This document provides an agenda for a NewYork MuleSoft Meetup session on DataWeave. The session will introduce DataWeave and cover topics like understanding arrays and objects, using mapping functions like map and mapObject, handling dynamic keys, common errors, dates and times, built-in functions, and a trivia quiz. The organizer and speaker will also be introduced. Attendees can register for the meetup at a provided URL.

1. NewYork MuleSoft Meetup
DataWeave Session 1
March - 6th -2021 , 11AM EST
Register now at https://meetups.mulesoft.com/
Sravan
Lingam
MuleSoft
Ambassador

2. Agenda
•Introduction Of Organiser and Speaker
•Presentation
•Introduction to DataWeave
•Understanding Array and Object
•Using map and mapObject
•How to have dynamic keys
•Flatten,pluck,reduce
•Common Errors we do
•Date and Time
•DataWeave functions
•Queries
•Trivia Quiz
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3. About the Organiser
Register now at https://meetups.mulesoft.com/

4. About the Speaker
Register now at https://meetups.mulesoft.com/
Sravan
Lingam
MuleSoft
Ambassador

5. DataWeave 2.0
•DataWeave is the MuleSoft expression language for accessing and
transforming data.
•We can Transform Data from one format to other . Eg: JSON to XML
•We can access any specific field inside a payload. Eg: payload.name
•Basically we can do all kind of Extraction and Transformation.
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6. Understanding Array and Object
•How to Identify an Object and an Array?
•An Object is always enclosed with { } and contains key-value pair.
•Eg:
•{ “name” : “Sravan” }
•{ “name” : “Sravan” , “id” : “2”}
•{ “Sravan” }
•{ “name” : “Sravan” , “2”}
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7. Understanding Array and Object
• An Array is always enclosed with [ ] and contains only values
• Eg:
• [“Sravan” , “2” ,”MuleSoft”]
• { “name” : [“Sravan”, “Lingam”]}
• [“name” : “Sravan”]
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8. Dataweave - The Power of Preview Feature
•Are you not sure about the syntax you want to write?
•Are you struggling to deploy your application always to check
whether your syntax or DW is correct or not?
•DataWeave Preview helps us to overcome it!
•Please make sure that your Tooling instance is running properly. or
else this feature won’t be available
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9. Transforming One Data Type To Other
•In Mule 3 ,we have separate connectors to convert from one type to other.
•In Mule 4 we use DataWeave to achieve this.
•Eg :
•JSON to XML
•XML to JSON
•JSON to CSV
•And many more….
•Note : Check the runtime versions and syntaxes that are supported to that Runtime
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10. map and mapObject
•map operator is used on Arrays.
•mapObject is used for Objects.
•You Cannot use mapObject operator for Arrays.
•You Cannot use map operator for objects.
•$ : Gives the value of the particular field/key.
•$$ : Gives index of the field
•Use of * ?
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11. How to Have dynamic Keys?
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12. Some of the most important and commonly
used operators
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Operator Can be applied on input which is/are Output type Used for
map On Arrays only Array Array of Object
mapObject On Objects only Object Output is an Object
reduce On Arrays Anything To reduce into given expression
pluck On Objects Array
Same as mapObject, only difference is the output is returned
as array instead of Object
flatten On arrays Single set of Array Turns into set of subarrays to single array

13. Dataweave - Date and Time
• now( )
• Timestamp for various TimeZones
• Converting Date - different formats
• Converting Date to String
• Converting String to Date
• Adding Days , Months, Years etc
• Days/Months between
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14. Cannot Coerce - Errors
• Null checks
• Default
• Converting String to Number, Number to String
• Very Important while developing
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15. Dataweave in other components
• We can write DW wherever required.
• In loggers to prints payload
• In choice router to write expression etc..
• Do you know how to add multiple variables and attributes in Transform message?
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16. Dataweave - Functions
• DataWeave Provides number of in-built functions for Data Transformation .
• Eg : upper , join , contains etc…
• You can write your own functions.
• You can also Write your DataWeave in separate scripts and call them!
• You can call a sub-flow or private flow using “lookup” in DataWeave
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17. Any Queries?

18. Next Meet up: Mar 13th,2021@10AM EST
Exploring MuleSoft as Multitenant platform and dive into its Platform and Operational Capabilities
by Mr Jitendra Bafna(Jacky)
https://meetups.mulesoft.com/events/details/mulesoft-new-york-city-presents-exploring-mulesoft-as-a-
multitenant-platform-and-dive-into-its-operational-and-platform-capabilities/#/
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19. Trivia Quiz !

20. Enter Your Full Valid Name (no nick Names are allowed)
Goto Mobile Browser
Enter :
kahoot.it

21. Read the options and Tap the colour which
has correct answer.

22. Thank you