Implicit and explicit monitoring

If you want to monitor websites, like online stores, there are two ways to do it. Implicit and explicit. Both methods have their advantages and disadvantages, so it is impossible to say which is the better solution. As so often in testing and monitoring "it depends".

Explicit monitoring

Explicit monitoring of web pages is the classic approach from test management. The aim is to test the features to be monitored directly and in detail. in detail. Let's take a search results page. This exists in almost all projects. If we would test it explicitly, we would start at the code level. code level. For example, we would take care of the component responsible for rendering the individual search result teasers. Now we should check that the component behaves correctly in all situations. So you add all possible data that could break such a component and monitor the behavior. and monitor the behavior.

So implicit testing and monitoring is all about examining individual components in detail and checking them for misbehavior.

Pros

• Causes of errors and not only the errors themselves are found
• Critical errors are found
• Small, non-critical errors are found
• More detailed tested source code is usually more readable and requires less maintenance

Cons

• High time expenditure
• Many theoretical errors do not occur during normal operation

Implicit monitoring

The most extreme variant of implicitly monitoring a search results page, as in the explicit example, would be to simply make a cUrl request to the page and check if a status code 200 is returned. This would mean that none of the hundreds of individual elements on the web page would crash this URL completely crashes. This always works very well when minor errors in the system, throw the whole thing off. Now you can of course get a little more detailed. In addition to the correct HTTP status code, you could also check if at least 10 search results are displayed. Or more simply, whether there are at least 10 elements with the class .searchResult.

Implicit and explicit monitoring of web pages are fundamentally different. With the one variant it concerns to discover with as little as possible expenditure as many as possible critical errors with as little effort as possible, while in the other the goal is an error-free web page.

Pros

• Very fast implementation
• Critical errors are found

Cons

• Small, non-critical, errors are not found
• Rare critical errors are not found

Comparison and recommendation

Both approaches have advantages and disadvantages and therefore also different areas of application. In our experience, the risk-based approach should be chosen. approach.

We always recommend implicit monitoring if you are just starting with quality assurance. You can achieve a lot with very little time and cost, without, for example, neglecting other important tasks. We also recommend this type of testing and monitoring for startups. Here it is usually important to first find out which features a customer wants before implementing them to perfection.

Explicit monitoring should always be used when it comes to critical elements. That is, website parts that either break down frequently or that are are very expensive if they break. In e-commerce, for example, the shopping cart and the checkout process should be tested once in a clean, automated way. the rest can be left implicit in the normal store.

Of course, there is no universal answer to the question of whether you should monitor your website implicitly or explicitly. The question you should always is how expensive a short feature failure would be.

koality.io and Leankoala

These two approaches to monitoring are exactly what we find in our two SaaS systems. koality.io takes care of the implicit part. As soon as all important page types of an online offer, the successful HTTP status codes are returned, the pages load quickly and do not contain any technical or content errors. content errors, there is a good chance that there are no critical problems.

With Leankoala, on the other hand, every detail of a web page can be monitored, click-throughs can be continuously tried out, and also own tests can be created. It is also important to understand that explicit tests usually mean more effort in maintenance. This must always be always keep this in mind.