Unrecognized XHR call


I’ve been (still) working through the DiscoverMeteor book’s Microscope project, and I had to leave for a few minutes to go to the store. I left my project running in Meteor with the console open.

When I came back, the console had these XHR connection error messages I didn’t recognize. From the stack trace, it’s clear that some internal part of the Post collection is making these calls, but I wasn’t sure why.

I’m just trying to understand how it’s working behind the scenes. Does anyone know what part of Meteor is making these XHR calls, and what it’s doing? Is this part of how Reactivity works behind the scenes?



Sorry, please ignore my n00bidity. I had several iTerm2 tabs open and did not realize my Meteor server had crashed. So that’s why the XHR calls were returning an error.

Still, if anyone can enlighten me, I would be interested to know which part of Meteor is making these calls and how it fits into the whole Reactivity and Data on the Wire organization. Thanks.