Social Networks for the life of the world
Many people surely know all this by now. Still, here are some things I’ve recently learned about notifying clients (browsers, API clients) about errors. Delivering errors from route handlers to clients This is remarkably easy, once you figure it out. Just use the http-errors package. (Beware, not the http-error package; it does something different. Call … Read more
I needed to do some simple web-page / Javascript debugging work on an Android device. My need was simple: look at the console log. But setting things up to do it was not simple. It didn’t help that most of the online information about this is buried in edits to years-old Stack Overflow answers. Desired … Read more
Sometimes it’s necessary in Javascript in a browser to find out whether an image object loads correctly. You might do this to check whether a server is responding, or whether it’s blocked by a firewall. In plain HTML you would load the image like this <img src=”/maybe.png” /> then look for the browser’s broken-image indicator … Read more
Stripe.com’s Stripe Elements is a great way to handle payment card information in a way that slows down cybercreeps. It’s secure because customers only enter card numbers into Stripe-furnished iframes, never into forms on the site taking payments via Stripe. Here is the sequence diagram for how Stripe Elements handles data flow
Software designers sometimes need to present UML sequence diagrams like this one. This kind of thing is absurdly fiddly to draw with most graphics packages. But there’s a language called PlantUML that allows us to write them as text and render them in various software tools, including WordPress with the plugin called PlantUML Renderer. The … Read more
What do you do if you have a bunch of different iframes in your web page posting messages? How do you know which iframe a message came from? Even if the iframe document comes from a different origin? This does the trick