Implementing a Custom Filter in AngularJS for Data Transformation During Migration Process
I've been struggling with this for a few days now and could really use some help. I'm performance testing and I've been banging my head against this for hours. I'm working on a project and hit a roadblock. Currently developing a migration project where I'm tasked with transforming data structures from one API format to another in an AngularJS 1.8 application. The challenge lies in creating a custom filter that applies necessary transformations while ensuring performance is not compromised. I've attempted to use built-in filters, but they don't meet our specific requirements. Here’s a snippet of what I’ve been experimenting with: ```javascript angular.module('myApp').filter('dataTransform', function() { return function(inputData) { // Custom transformation logic const transformedData = inputData.map(item => { return { id: item.oldId, name: item.oldName.trim(), value: item.oldValue * 2 // Example transformation }; }); return transformedData; }; }); ``` After registering this filter, I used it in my controller: ```javascript angular.module('myApp').controller('DataController', ['$scope', 'dataService', function($scope, dataService) { dataService.getData().then(function(response) { // Applying filter $scope.transformedData = $filter('dataTransform')(response.data); }); }]); ``` However, performance seems to degrade when working with larger datasets (thousands of records). I noticed that the filter is called on each digest cycle, which might be causing the slowdown. Is there a way to optimize this? I tried using `track by` in my `ng-repeat`, but it didn’t yield a significant improvement. Additionally, I reviewed AngularJS documentation and community discussions but haven’t come across a solid strategy for optimizing custom filters in this context. Any advice on best practices for managing performance with data transformation filters would be greatly appreciated! What's the best practice here? What would be the recommended way to handle this? For reference, this is a production desktop app. How would you solve this? The stack includes Javascript and several other technologies. This is happening in both development and production on macOS. I'd really appreciate any guidance on this.