Saved by our automated tests

Chris Downey

Founder, VaxCalc Labs and creator of Autovist and the Vaccine Ingredients Calculator.

Latest posts by Chris Downey (see all)

A test I wrote 1.5 years ago just saved us from embarrassment and helped me quickly hone in on a problem I accidentally introduced along with a new feature.

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Email to Yahoo is not being delivered

Chris Downey

Founder, VaxCalc Labs and creator of Autovist and the Vaccine Ingredients Calculator.

Latest posts by Chris Downey (see all)

Looking through the Vaccine Ingredient Calculator (VaxCalc) user registration logs this morning, I noticed something strange.  Yesterday, we had a good number of signups, yet all the non-confirmed email addresses are from Yahoo email user accounts.  Why?

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Pre-calculating vaccine ingredients: from PostgreSQL to HTML data-*

Chris Downey

Founder, VaxCalc Labs and creator of Autovist and the Vaccine Ingredients Calculator.

Latest posts by Chris Downey (see all)

The VIC pre-calculates ingredient amounts in order to dramatically speed-up performance.  This article describes how its done and why AJAX would be the absolute worst way of doing dynamic calculations on a complex set of variables.

The VIC delivers a tiny database to the browser inside the Ingredient Report page. The data is stored as HTML data-* and the engine is Javascript. “By adding data-* attributes, even ordinary HTML elements can become rather complex and powerful program-objects.” [1]

Once the Ingredient Report is loaded…

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Create custom URL-click tracker in less than 5 minutes

Chris Downey

Founder, VaxCalc Labs and creator of Autovist and the Vaccine Ingredients Calculator.

Latest posts by Chris Downey (see all)

Google Analytics is a powerful tool when your site has thousands of visitors a day or more. But it isn’t so good at showing you the most popular links on your site; nor does it allow you to work directly with the data your site generates and sends to it.

The reason we wanted to do this is because the Vaccine Ingredient Calculator’s Ingredient Report has a huge amount of links for more information and it would be really helpful to know the order in which our VIC users find them to be useful.  Depending upon vaccine choices, there could be up to 90 links!

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Yikes! ReferenceError: Can’t find variable: Set

Chris Downey

Founder, VaxCalc Labs and creator of Autovist and the Vaccine Ingredients Calculator.

Latest posts by Chris Downey (see all)

ReferenceError: Can’t find variable: Set

This Javascript error just blew our VIC calc engine design right out of the water.

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