Coding Snippets

Correlating Services in App Insights

When one service call another service it is important when troubleshooting latency issues to know how long each service is taking to process, it’s also important to see the stack of calls that happen across both services to help track down errors. To do this you…

Analyse your Ionic App Size

Here’s a tip on analyzing your bundle size, the dependencies your app relies on and how to quickly identify…

Turning Off Change Detection for Performance in Ionic

Angular’s change detection is usually quite great, but I found a case where it’s performance was terrible on a page that contained a long vertical list of horizontal lists of images (think the soundcloud home page where there are lots of…

Fixing IOS 11 web apps (apple-mobile-web-app-capable)

Optimizing Javascript DateTime formatting (50x perf)

Formatting dates and times in javascript can be very expensive in terms of CPU cost. Take this simple piece of code that formats a string value like "2017-12-27T16:37:37.417Z" to 8:37 AM

Gulp.src missing all files

In a gulp script that’s been working for years:

gulp.src(["*.js", "!*.spec.js"])

I found that after installation of gulp globally on a new build server that the above line was returning no files. So had the modify it to:

Rxjs 5.5 “ Property ‘map’ does not exist on type Observable…’”

I’ve just converted an Ionic app to Angular 5 which relies on rxjs 5.5+. One of the odd errors that i found and didn’t quite understand why was “Property ‘map’ does not exist on type Observable” (or any operator like take…

Traversing through a Javascript Object

I’ve started working with Firebase on a project and one of the interesting quirks with storing json data in its real-time database is that objects cannot have any properties that are undefined (you get “ Error: Firebase.set failed: First argument contains…