# `array` Functions Use `array` functions in rules to manipulate arrays in asset JSON at runtime. Array functions can use the answer to a configuration wizard question to set runtime conditions. For example, array functions can check all selected values and set a condition to true or false. They can also take multiple values from an answer and iterate over a JSON array to put those values into the runtime JSON correctly. Or, say that your wizard contains multiple questions with limited values to choose from, such as Yes/No, or a time frame in days or months. An array function can replace them with one question that asks the user to select multiple features to include in dashboards. In this case, the array function loops over the one question to check for values and set the features that the user picked via a conditional. ## `forEach` Parameters: `Collection array`, `String returnValue` Returns: `Collection` Recursive: Not supported Description: Evaluates `returnValue` as an EL expression for each item in the given array and collects each `eval` result in an array and returns it. ### Example Variables: ``` myArray = ["ProductName","Amount", "CompanyName", "Revenue"] ``` JSON template: ```json {    "fields": "${array:forEach(Variables.myArray, '{\"name\": \"${var}\"}')}" } ``` Returns: ```json {    "fields": [{"name": "ProductName"},               {"name": "Amount"},               {"name": "CompanyName"},               {"name": "Revenue"}] } ``` ## `forEachIndex` Parameters: `Int start`, `Int end`, `String returnValue` Returns: `Collection` Recursive: Not supported Description: Evaluates `returnValue` as an EL expression for the index number(s) in the array where the string is found. ### Example JSON template: ```json {    "fields": "${array:forEachIndex(1, 5, '{\"index\":\"${index}\"}')}" } ``` Returns: ```json {    "fields": [{"index": "1"},               {"index": "2"},               {"index": "3"},               {"index": "4"}, {"index": "5"}] } ``` ## `concat` Parameters: `Collection array1`, `Collection array2` Returns: `Collection` Recursive: Not supported Description: Returns an array after concatenating the given `array1` and `array2`. ### Example Variables ``` myArray1 = ["A", "B", "C"] myArray2 = ["X", "Y", "Z"] ``` JSON Template: ```json {    "concat": "${array:concat(Variables.myArray1,Variables.myArray2)}" } ``` Returns: ```json { "concat": ["A", "B", "C", "X", "Y", "Z"] } ``` ## `unique` Parameters: `Collection array` Returns: `Collection` Recursive: Not supported Description: Returns an array of unique items. Uniqueness determined by the underlying objects contained in the array. For example, if the collection is an array of strings, all strings with identical values (case-sensitive) are removed. ### Example Variables: ``` myArray = ["ProductName","Amount", "CompanyName", "Revenue", "Amount", "ProductName"] ``` JSON template: ```json {    "unique": "${array:unique(Variables.myArray}" } ``` Returns: ```json {    "unique": ["ProductName", "Amount", "CompanyName", "Revenue"] } ``` ## `uniqueBy` Parameters: `String byFieldName`, `Collection array` Returns: `Collection` Recursive: Not supported Description: Returns an array of unique items. Expects an array of complex objects of similar shape. Uniqueness determined by comparing the value of a field identified by the given `byFieldName`. ### Example Variables: ```json myArray = [{"name" : "ProductName", "id" : "1"}, {"name" : "Amount", "id" : "2"}, {"name" : "CompanyName", "id" : "3"}, {"name" : "Amount", "id": "2"}] ``` JSON template: ```json {    "uniqueBy": "${array:uniqueBy('id', Variables.myArray}" } ``` Returns: ```json {    "uniqueBy": [{"name" : "ProductName", "id" : "1"}, {"name" : "Amount", "id" : "2"}, {"name" : "CompanyName", "id" : "3"}] } ``` ## `union` Parameters: `Collection array1`, `Collection array2` Returns: `Collection` Recursive: Not supported Description: Returns a unique union between `array1` and `array2`. Uniqueness determined by the underlying objects contained in the array. ### Example Variables: ```json myArray1 = ["ProductName", "Amount", "CompanyName"] myArray2 = ["Revenue", "Amount", "ProductName"] ``` JSON template: ```json {    "union": "${array:union(Variables.myArray1, Variables.myArray2}" } ``` Returns: ```json {    "union": ["ProductName", "Amount", "CompanyName", "Revenue"] } ``` ## `unionBy` Parameters: `String byFieldName`, `Collection array1`, `Collection array2` Returns: `Collection` Recursive: Not supported Description: Returns an array which is a union of `array1` and `array2` items. Expects an array of complex objects of similar shape. Uniqueness determined by comparing the value of a field identified by the given `byFieldName`. ### Example Variables: ```json myArray1 = [{"name" : "ProductName", "id" : "1"}, {"name" : "Amount", "id" : "2"}, {"name" : "CompanyName", "id" : "3"}] myArray2 = [{"name" : "Revenue", "id" : "4"}, {"name" : "Amount", "id" : "2"}] ``` JSON template: ```json {    "unionBy": "${array:unionBy('id', Variables.myArray1, Variables.myArray2}" } ``` Returns: ```json {    "unionBy": [{"name" : "ProductName", "id" : "1"}, {"name" : "Amount", "id" : "2"}, {"name" : "CompanyName", "id" : "3"}, {"name" : "Revenue", "id" : "4"}] } ``` ## `contains` Parameters: `Collection array`, `Object item` Returns: `Boolean` Recursive: Not supported Description: Returns `true` if the given item is in the given array, otherwise `false`. ### Example Variables: ``` myArray = ["ProductName","Amount", "CompanyName", "Revenue"] ``` JSON template: ```json {    "contains": "${array:contains(Variables.myArray, 'Amount')}" } ``` Returns: ```json {    "contains": true } ``` ## `size` Parameters: `Collection array` Returns: `Integer` Recursive: Not supported Description: Return the size of the array. ### Example Variables: ``` myArray = ["ProductName","Amount", "CompanyName", "Revenue"] ``` JSON template: ```json {    "size": "${array:size(Variables.myArray)}" } ``` Returns: ```json {    "size": 4 } ``` ## `last` Parameters: `Collection array` Returns: `Object` Recursive: Not supported Description: Return the last item of the array. ### Example Variables: ``` myArray = ["ProductName","Amount", "CompanyName", "Revenue"] ``` JSON template: ```json {    "last": "${array:last(Variables.myArray)}" } ``` Returns: ```json {    "last": "Revenue" } ```