http - What does this error mean: HPE_INVALID_CONSTANT?

Question

I was receiving HPE_INVALID_CONSTANT when making HTTP requests with NodeJS the other day. They mysteriously stopped occurring recently, but I'm still baffled and curious what exactly HPE_INVALID_CONSTANT is trying to tell me.

My google search results are a bit slanted towards NodeJS, so I'm not picking up anything that describes more generally what this means. It looks like a system level error since it's all caps.

Answer 1

Think this answer is lated, but it can help some people.

I also had this problem and realized NodeJS doesn't support HTTP 0.9, that server's response contains no headers. In fact, in NodeJS documentation shows support to 1.0 and 1.1 http requests.

You can read a little more here in this issue.