DataWeave Examples

Shows common selector expressions for extracting values from a data source, such as a Mule message.

Uses a single-value DataWeave selector (.) to extract data from XML elements.

Shows some common ways to set default values.

Shows how to use and change the settings for reading and writing data formats, such as application/csv.

Uses selectors to perform a basic format transformation. It does not use any functions.

Shows how to customize the MIME type of a given format output, including an example of a JSON output with application/problem+json MIME type.

Uses map to reorganize fields in a JSON array. It uses as to coerce a String into a Number.

Uses flatMap to map objects in an array and flatten the resulting array.

Uses mapObject to go through the keys and values in each object, and set all the keys to upper case.

Uses the mapObject function to iterate through an array of objects and appends a new object that matches the value of the specified criteria.

Uses the multi-value selector to pick out the keys in an object that are named "book", these are returned as an array. It then uses map to iterate through the array this creates.

Transforms the payload according to definitions sent in a variable. It defines a function that applies the logic defined in the variable, using map and default.

Uses filter to return rows that contain a specified value.

Uses filter with map to look up data in a CSV file and return a country code for each calling code found within an input array of phone numbers.

Converts a file stream into Base64 and converts a Base64 string into a file stream. Uses a PDF file as the input and output.

Calls Java methods from a Java class in a Mule project.

Renames some keys in a JSON object while retaining the names of all other keys in the output. Uses mapObject, if, as, and and.

Uses if with map to determine whether to include a field in the output. You might use it to exclude fields that contain sensitive data.

Uses mapObject to apply changes to the keys in an object, depending on the type of their corresponding values. Uses camelize, capitalize, and pluralize depending on the if and else if statement.

Uses groupBy, mapObject, and map to reorganize JSON and XML fields.

Uses zip to rearrange pairs of similar arrays so that they form a series of touples with the matching values from each.

Uses groupBy and map to sort a list of candidates according to their score at a test, then it splits the array to select only the top candidates.

Masks sensitive data by changing values of some keys to asterisks (****`). Uses mapObject, if, and else.

Shows how to exclude unwanted elements from the output. Uses the - (remove) and mapObject functions.

Defines a series of constant strings and numbers in the header, these are used to filter input and to concatenate into URLs. Uses map, if and ++ to concatenate strings.

Defines a function that obtains totals and subtotals through the accumulator function. Also performs additions, subtractions, and multiplications of numeric values.

Uses reduce, map, if, and splitBy to modify and conditionally output fields from a list.

Uses flatten, the object constructor braces ({}), and selectors to flatten subarrays and nested elements in arrays. Uses concatenation (++) to combine arrays before flattening them and uses the ..* descendants selector on a key to select values from a flattened list.

Shows uses of regular expressions in arguments to several DataWeave functions.

Uses inlineCloseOn="empty" to close empty tags (for example, <element2/>).

Uses the @(key:value) syntax to create an XML attribute.

Defines a function that recursively checks an element and all of its children for a specific XML attribute and removes it with -. It also uses mapObject, if and is (to match types).

Pass XML attributes from the input source payload to the output XML. It uses the dynamic attribute expression @dynamicAttributes to create the attributes of the new output tag by selecting the attributes dynamically from the input.

Defines multiple XML namespaces and references these in each tag.

Removes all objects that contain a set of key-value pairs from an array of objects. Uses filter with contains and a not operator.

References data on the payload, a message attribute and a variable. It then processes these through map, filter and multiplications.

Reference data that arrives in multiple separate payloads from one single Mule event. Filters the output based on a unique identifier. Uses map, using, as, and filter functions.

Defines a function that normalizes conflicting date formats into a single, common format. Uses mapObject, replace and as to coerce a data type.

Performs multiple math operations combining different types related to date and time.

Uses >> with a time zone ID to change a time zone and provides a list of available time zone IDs.

Uses formatting characters such as uuuu/MM/dd to change the format of dates and times. Creates a date-time format using a custom DataWeave type.

Uses mapObject to iterate over a multipart payload and extract data from each part. It also uses read with a boundary value to read the multipart content.

Defines a function that reduces a list of elements into one field. It then calls this function only when a certain field has values. Uses map, reduce, splitBy, if and ++ to append to an array.

Defines a function that expects to receive two inputs: a function to apply and an element to apply it on. The function is also recursively applied to the element’s children. It uses mapObject lower is if/else.