Docker: Why port forwarding is not working with go tour? -

dockerfile

from golang:latest expose 3999 entrypoint ["go", "tool", "tour"]

i'm running docker run -d -p 127.0.0.1:3999:3999 "hubusername/docker-tour:v1"

but $ curl http://localhost:3999 returns error:
curl: (56) recv failure: connection reset peer

of course, ip:3999 in browser doesn't work too.

p.s. docker run -d -p 8081:80 nginx:alpine works perfect

ok, i've setted 0.0.0.0 host go tour application adding line:

cmd ["-http", "0.0.0.0:3999", "-openbrowser=false"]

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