SuiteScript - Map/Reduce summarize - mapreduce

Question

I am writing a map/reduce script to search for a custom record and create a CSV file from its results.
Firstly, in the getInputData() creating a search and returning its results.
After that comes the map function where I am using JSON.parse to parse the result values.
I have an array declared globally as var data = '' in which I am pushing the values I get in map function.
But when all the looping ends in map() and it enters summarize(), the data array becomes empty again.
I want that data array to be called in summarize() where I can use file.create() function to create the csv file.
I used return data; in map() but it is showing as empty when in summarize().

Answer 1

You have to use context.write at the end of map to send data to the next stage.
context.write({
key: key,
value: value
});
Adding a simple script to show how to access values in the summarize stage:
/**
*#NApiVersion 2.x
*#NScriptType MapReduceScript
*/
define([],
function () {
function getInputData() {
return [{
id: 1,
value: 'abc'
}, {
id: 2,
value: 'def'
}];
}
function map(context) {
var value = JSON.parse(context.value);
context.write({
key: value.id,
value: value.value
});
}
function summarize(context) {
var values = [];
context.output.iterator().each(function (key, value) {
log.debug({
title: 'Output for key ' + key,
details: value
});
values.push(value);
return true;
});
log.debug({
title: 'Summary',
details: JSON.stringify(values)
});
}
return {
getInputData: getInputData,
map: map,
summarize: summarize
}
});