Ordinary site monitoring asks three things: does the URL connect, what’s the status code, and how long did the response take.<\/p>\n
All three are about whether the server responded. None of them looks at the content.<\/p>\n
The frame of the page comes from a template, and the content in the middle is filled in from a data source. When the data source comes back with nothing, the frame still renders as usual.<\/p>\n
The result is a page with a 200. Title, menu, footer and the whole structure are there, and the middle is empty.<\/p>\n
The monitoring reports everything normal. Visitors see a blank page.<\/p>\n
Our checks no longer look at the status code. They look at how much text is in the main content area.<\/p>\n
They grab the main content block, strip the tags and count what’s left. Below the threshold it goes red, whatever the status code is.<\/p>\n
Thresholds have to be set page by page. A normal article listing and a normal contact page can differ in word count by a factor of ten. For pages where you really can’t settle on a number, at least require that it isn’t zero.<\/p>\n
A batch job that returns 0 when it’s done means it finished, not that it processed anything. Process 300 records and you get 0. Process none and you also get 0.<\/p>\n
A file existing doesn’t mean there’s anything in it. A write that fails halfway often leaves a 0-byte file behind, and most downstream programs only check whether the file is there.<\/p>\n
So when we see a green light, we ask one more question: does it prove “it ran,” or “the thing is there”?<\/p>\n","protected":false},"excerpt":{"rendered":"
Monitoring says the site is fine. The header, menu and footer are all there. Only the middle is blank.<\/p>\n","protected":false},"author":1,"featured_media":1014,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_post_was_ever_published":false},"categories":[29],"tags":[],"class_list":["post-2148","post","type-post","status-publish","format-standard","has-post-thumbnail","category-web-notes-en-us"],"yoast_head":"\n