Simon icon Simon
Flexible server monitoring

Dejal Simon is the essential site monitoring tool for macOS. It checks servers for changes or failures, and notifies you via email, sound, speech, Twitter, or other means. You can use it to track updated sites, and to alert you when an important server goes down or recovers. It is a native macOS application with an intuitive and attractive interface.

Simon is very versatile. It can be used to monitor your own website and servers, track posts and new comments on your or friends' blogs, check for web mail, get notifications of updates to favorite news and entertainment websites, keep an eye on auctions, and many other uses.

Monitor Your Sites and Servers

Central to Simon is the Monitor window. It enables you to see at a glance the current status of all of your monitored websites, servers, and applications. In addition to a colorful status icon and up-time percentage, the tests list displays how long ago the last change and failure occurred, and when the next check will occur. But that's not all. This window also displays further statistics about the tests, and a log showing recent activity, including when tests start checking, and the various steps during the check (starting, stopping, service result, each filter, notifications, etc), plus other actions on tests, e.g. editing, pausing, etc. It also has logs of checks (including the check duration), changes (including the text that changed), and failures (including the error description).

[Monitor window]

Tests (and other lists) are organized into groups, and you can add your own groups and move them around as desired. This enables you to arrange tests by server, type, client, or whatever else makes sense to you.

Because sometimes you don't want to have another window cluttering up your screen, you can hide the Monitor window if you wish, and/or use the handy Dock or Status menus. The Dock menu includes quick access to Simon's windows, and some global functions. The Status menu includes all that plus displays all of your tests, complete with status icons, details via tooltip, and the option to perform a favorite action or display a sub-menu of quick-access operations for each test, so you can visit the site or other tasks without even having Simon visible.

If you prefer, Simon can be hidden from the Dock, so it is only accessed via the Status menu. Access to Simon can also be restricted, requiring a password, if you wish.

Put it to the Test

So how do you tell Simon what to monitor? That's where the Test Info pane comes in. It is accessed when the Tests list is active. It shows a summary of the test; click the heading for each line of the summary to jump right to that page. It includes an Edit button to enable modifying the test, which toggles to Done when editing to switch back to the summary.

In Edit mode, the Info pane has lots of options to help you configure each test, conveniently arranged on multiple pages:

[Monitor window]

Yes, of course Simon supports dark mode.

Note: Simon automatically detects when you don't have a network connection, and waits for it to return. Plus if you run Simon on a laptop that you often take to Wi-Fi hotspots, you can enable an option in the preferences to detect hotspot login pages, to avoid interpreting them as a change or failure in the monitored website.

The Web Page service is one of the most popular, for monitoring normal web pages (as opposed to other things like local Applications). The Setup Assistant makes it easy to mass import bookmarks from web browsers, picking and choosing which to import. Also, you can simply drag a URL from a browser or other application to the Monitor window to add it as a new test.

[Monitor window]
At Your Service

Several services come built-in. Services tell Simon how to check a test. They include, among others:

Usually the built-in services are ample, but what if you want to delve deeper? Sometimes you have a special requirement and want to check some other kind of server. Not a problem! You can customize the services to edit the defaults for the built-in ones, or even add new ones. Similar to the Test Info pane, the Service Info pane enables you to change the services — and lets you auto-pause a service, affecting all tests that use that service.

Prescription for Success

Simon is all about flexibility, but perhaps one of the most powerfully flexible features is the Script service plug-in. It enables you to create your own services via AppleScript, shell script, or Perl, PHP, Python, and other scripting languages.

The Script editor enables adding a description to display, custom variables to get values from tests that use the new service, selecting the script type, and of course editing the script itself.

You can get new scripts from the Simon Extras page, or if you write one that you're willing to share, you can save it and send it to us to provide for others.

[Monitor window]
Capture Your Heart's Desire

Services based on the Port service plug-in enable you to connect to any server and engage in a conversation with it, receiving text and sending responses. If the session script is successfully navigated, the check is considered a success, but if the server doesn't respond, or responds incorrectly, a failure is registered.

There are session scripts built-in for several types of servers. But how do you create your own? Simon makes it easy, with the handy Capture Session panel.

You connect to any server on a given port, select the relevant part of incoming text, type commands to continue the session, and the session script is created for you. Simple as that!

Put a Detective on the Job

But what about websites that have banners or other irrelevant content? Won't that confuse Simon into thinking the page has changed? Nope! Simon has a very useful feature called Filters, where you can tell it what part of the page to look for, e.g. a comment count on a blog, or the lead headline area on a news site. Filters can also optionally detect if the output is different than the previous time they checked.

Multiple filters can be chained to perform operations on the text output by the service. They can also look at the output of any previous filters, and other values, specified as the input for each filter.

Like services, filters can be customized as desired via the Filter Info pane and used in any number of tests. Many filters define default behavior that can be customized for each test, for maximum flexibility.

The provided filters include:

Want to do something else? No problem: you can add custom filters by writing an AppleScript, shell script, or Perl, Python etc script. Like the Script service, the Script filter plug-in enables a virtually infinite range of filtering options.

To make it easier to find text for the Filter feature, or just to quickly view the site without leaving Simon, Preview pane is available. The Preview pane includes the rendered content, HTML source and server headers of the page, plus the output of each filter for the test. You can also easily view the sites in your preferred web browser. Preview is also available for non-web services, to see what is output by the server and the filters.

[Monitor window]
Communication is the Best Policy

Okay, so Simon monitors your tests, detecting changes, failures, and recoveries. And it displays this information in the Monitor window, Dock icon, and Status menu. But you're a busy person, and sometimes want important events to really catch your attention. You're in luck: Simon also has a notifiers feature, with several ways of telling you about things you want to know. Each test can use any number of notifiers, with separate notifiers for each type of event. So, for example, you could play a sound and go to the web page when your favorite blog changes, but email a text message to your cellphone when it goes down.

Further, you can share notifiers between multiple tests: set up a notifier once, and use it for as many tests as you like. For additional flexibility, variables enable customizing the notifier with test names, URLs, times, etc.

Available notifiers include:

As with services and filters, you can add custom notifiers by writing an AppleScript, shell script, or Perl, Python etc script. The Script notifier plug-in enables a virtually infinite range of notification options. You can also create notifiers based on port connection sessions via the Port notifier plug-in.

But as useful as notifiers are, sometimes you don't want to be bothered... perhaps during a meeting, or while you sleep if your computer is within earshot. As with tests, notifiers can be automatically paused for specified time and day ranges.

[Monitor window]
Your Reporter on the Scene

[Report feature]What if you're using a different computer, and don't want yet more email, or want to see more detail? Simon also offers a reports feature, that outputs multi-page HTML reports that you can view in any web browser. Simon can automatically save them to your local Personal Web Sharing folder (or any other local folder), or upload them to a remote server, at whatever frequency you like. Click to see a live sample!

The reports use templates to manage layout and content, with several templates built-in, and updates and user-submitted ones available on the Simon Extras page. They aren't limited to HTML, either — there are templates for a RSS feed, tab-delimited text files, and other possibilities... including an iPhone template: click to see it live.

Try It Now!

Download and try Simon for free! Version 5.1.1 is currently the latest release. Read the Simon 5.1.1 release notes to see what has changed in this version, or read the Simon Help to find out more about it.

Also Available on Setapp

Would you prefer a subscription? Simon is also included as one of the apps on Setapp, a popular third-party service where you can get many excellent apps for one low monthly price — and you can try it free for a week. Learn more....