DataWeave: Play With Dates (Part 1)

DataWeave is a very powerful language provided by MuleSoft to transform data. It is the primary language of MuleSoft for data transformation and an expression language for components and connectors configuration.

This blog gives very good insights into the very basic date operations or functions that a developer would be using on a regular basis.

1. Find the number of days between two dates
2. Find if a given date or date time is a leap year
3. Add days to the current date or any provided date
4. Subtract days from the current date or any provided date
5. Add and subtract years to the current date or any provided date
6. Change a Time Zone
7. Find the latest DateTime, Date, Time from a given list of DateTimes

1. Find the Number of Days Between Two Dates

The daysBetween DataWeave function can be used to find the number of days between any two dates. This can be applied in scenarios where you need to find the number of days between the start and end dates of a membership/contract. The data type of the output generated by this function is "Number."

This function accepts two mandatory parameters, and the type of parameters should always be either in date or date time.

This function does not accept null or empty strings. It gives an error if any values are provided as input parameters other than date or date times.

Input

{
    "membership": {
        "startDate": "27-05-2023",
        "endDate": "27-06-2025"
    }
}

DataWeave Expression

%dw 2.0
output application/json
---
{
"numberOfDays" : daysBetween((payload.membership.startDate as Date {format:"dd-MM-yyyy"}), payload.membership.endDate as Date {format:"dd-MM-yyyy"})
}

Output

{
  "numberOfDays": 762
}

2. Find Out if a Given Date or Datetime Is a Leap Year

The isLeapYear DataWeave function can used to find if any given date or datetime is a leap year. This function gives true if a date or datetime is a leap year; otherwise, it returns false. This can be applied in scenarios where a company plans to provide any discounts or offers for the membership fee if the membership is being created in a leap year. The data type of the output generated by this function is "Boolean."

This function accepts a mandatory parameter, and the type of the parameter should always be either in date or date time.

This function does not accept null or empty strings. It gives an error if any values are provided as input parameters other than date or date times.

DataWeave Expression

%dw 2.0
output application/json
---
{
    "leapYearTest1" : isLeapYear(now()),
    "leapYearTest2" : isLeapYear("27-06-2025" as Date {format:"dd-MM-yyyy"}),
    "leapYearTest2" : isLeapYear("2023-09-23T13:59:35.340539Z")
}

Output

{
  "leapYearTest1": true,
  "leapYearTest2": false,
  "leapYearTest2": false
}

3. Add Days to the Current Date or Any Provided Date

The DataWeave examples below show multiple ways to add days to a date and DateTime. All the dataweave examples added below are for dataweave 2.x, which is only available in Mule 4.x.

The examples below use:

• as function to coerce a String to Period type
• P<date>T<time> for the Period data type, which provides designators for years, months, days, hours, minutes, and seconds
  For example, |P2Y9M1D| refers to a period of two years, nine months, and one day, and |PT5H4M3S| indicates a time period of five hours, four minutes, and three seconds.

DataWeave Expression

%dw 2.0
output application/json
var numberOfDays = 3
---
{
  oneDayAfter: |2023-10-01T23:57:59Z| + |P1D|,
  threeDaysAfter: |2023-10-01T23:57:59Z| + ("P$(numberOfDays)D" as Period),
  a: |2020-10-01| + |P1D|,
  b: |P1D| + |2020-10-01|,
  c: now() + |P1D|
}

4. Subtract Days From the Current Date or Any Provided Date

The DataWeave examples below show multiple ways to subtract days from a date and DateTime. All the dataweave examples added below are for dataweave 2.x, which is only available in Mule 4.x.

The examples below use:

• as function to coerce a String to Period type
• P<date>T<time> for the Period data type, which provides designators for years, months, days, hours, minutes, and seconds
  For example, |P2Y9M1D| refers to a period of two years, nine months, and one day, and |PT5H4M3S| indicates a time period of five hours, four minutes, and three seconds.

DataWeave Expression

%dw 2.0
output application/json
var numberOfDays = 3
---
{
  oneDayBefore: |2019-10-01T23:57:59Z| - |P1D|,
  threeDaysBefore: |2019-10-01T23:57:59Z| - ("P$(numberOfDays)D" as Period),
  a: |2024-01-06| - |P1D|,
  b: |P1D| - |2023-10-01|,
  c: |2023-10-01T23:57:59Z| - |P1D|,
  d: |2023-10-01T23:57:59| - |P1D|,
  e: |2019-10-01| - |2018-09-23|,
  f: |2019-10-01T23:57:59Z| - |2018-10-01T23:57:59Z|,
  g: |2019-10-01T23:57:59| - |2018-10-01T23:57:59|,
  h: now() - |P1D|
}

Output

{
  "oneDayBefore": "2019-09-30T23:57:59Z",
  "threeDaysBefore": "2019-09-28T23:57:59Z",
  "a": "2024-01-05",
  "b": "2023-09-30",
  "c": "2023-09-30T23:57:59Z",
  "d": "2023-09-30T23:57:59",
  "e": "PT8952H",
  "f": "PT8760H",
  "g": "PT8760H",
  "h": "2024-01-04T08:23:13.448587Z"
}

5. Add and Subtract Years To Current Date or Any Provided Date

The DataWeave examples below show multiple ways to add and subtract years from a date and DateTime. All the dataweave examples added below are for dataweave 2.x, which is only available in Mule 4.x.

The examples below use:

• as function to coerce a String to Period type
• P<date>T<time> for the Period data type, which provides designators for years, months, days, hours, minutes, and seconds
  For example, |P2Y9M1D| refers to a period of two years, nine months, and one day, and |PT5H4M3S| indicates a time period of five hours, four minutes, and three seconds.

DataWeave Expression

%dw 2.0
output application/json
var numberOfYears = 3
---
{
  oneYearBefore: |2023-10-01T23:57:59Z| - |P1Y|,
  threeYearsBefore: |2023-10-01T23:57:59Z| - ("P$(numberOfYears)Y" as Period),
  a: |2023-12-01| - |P2Y|,
  b: |P2Y| - |2019-10-01|,
  c: |2023-10-01T23:57:59Z| - |P1Y|,
  d: |2023-10-01T23:57:59Z| + |P1Y|,
  e: |2023-10-01T23:57:59| - |P1Y|,
  f: |2019-10-01| - |2018-09-23|,
  g: |2019-10-01T23:57:59Z| - |2018-10-01T23:57:59Z|,
  h: |2019-10-01T23:57:59| - |2018-10-01T23:57:59|,
  i: now() - |P1Y|,
  j: now() + |P1Y|
}

Output

{
  "oneYearBefore": "2022-10-01T23:57:59Z",
  "threeYearsBefore": "2020-10-01T23:57:59Z",
  "a": "2021-12-01",
  "b": "2017-10-01",
  "c": "2022-10-01T23:57:59Z",
  "d": "2024-10-01T23:57:59Z",
  "e": "2022-10-01T23:57:59",
  "f": "PT8952H",
  "g": "PT8760H",
  "h": "PT8760H",
  "i": "2023-01-05T08:28:34.739095Z",
  "j": "2025-01-05T08:28:34.739098Z"
}

6. Change a Time Zone

The DataWeave example below presents a way to change the time zone in MuleSoft using DataWeave.

The example uses >> operator and a time zone ID to change the time zone. It also uses the formatting characters uuuu-MM-dd'T'HH:mm:ss.SSS to modify the format. The uuuu characters represent the year. 

The expression below uses a custom function, "format," which takes a parameter of type "DateTime." 

DataWeave Expression

%dw 2.0
output application/json
fun format(d: DateTime) = d as String {format: "yyyy-MM-dd'T'HH:mm:ss.SSS"}
---
{
    CreatedDateTime: format(|2019-02-13T13:23:00.120Z| >> "CET"),
}

Output

{
  "CreatedDateTime": "2019-02-13T14:23:00.120"
}

7. Find the Latest DateTime, Date, Time From a Given List of DateTimes

The DataWeave example below presents a way to find the latest DateTime, Date, and Time from inputs defined in the variables myDateTime1 and myDateTime2. It also shows that the function returns null on an empty array.

DataWeave Expression

%dw 2.0
var myDateTime1 = "2017-10-01T22:57:59-03:00"
var myDateTime2 = "2018-10-01T23:57:59-03:00"
output application/json
---
{
  myMaxBy: {
    byDateTime: [ myDateTime1, myDateTime2 ] maxBy ((item) -> item),
    byDate: [ myDateTime1 as Date, myDateTime2 as Date ] maxBy ((item) -> item),
    byTime: [ myDateTime1 as Time, myDateTime2 as Time ] maxBy ((item) -> item),
    emptyArray: [] maxBy ((item) -> item)
  }
}

Output

{
  "myMaxBy": {
    "byDateTime": "2018-10-01T23:57:59-03:00",
    "byDate": "2018-10-01",
    "byTime": "23:57:59-03:00",
    "emptyArray": null
  }
}

Conclusion

This blog has covered various operations that can be performed on Years, DateTimes, Dates, and Times in Mulesoft using Dataweave through a series of Datweave examples and Datweave scripts.