Update configs to Prometheus v2

[eduponte]

This PR updates some of the configs that didn't work with Prometheus 2.0:

• Command options on prometheus docker.
• Alert rules format, now a yml file.

[vegasbrianc]

@llitfkitfk @philicious When you have a chance could you provide feedback on this? I will be testing it today and will do the same.

[llitfkitfk]

LGTM
https://labs.play-with-docker.com/p/b8200ggmi3v000bagpk0#b8200ggm_b8200hgmi3v000bagpkg

[eduponte]

So cool @llitfkitfk I took the liberty of uploading the dashboards to make sure everything was working:
http://ip172-18-0-15-b8200ggmi3v000bagpk0-3000.direct.labs.play-with-docker.com/dashboard/db/docker-dashboard?refresh=10s&orgId=1

[llitfkitfk]

if the PWD support volume github config file, I think we can add a Try in PWD stack in README.
ref: https://medium.com/@marcosnils/showcasing-your-applications-with-docker-in-a-single-click-9e9fa2908c51

[philicious]

might have time tomorrow

[llitfkitfk]

@eduponte
no need to add .yml to alert.rules

[philicious]

I tried out this PR and everything is starting up and running fine.
however, when I caused an high-load alert, I could see it in Prometheus http://127.0.0.1:9090/alerts but not in Alertmanager http://127.0.0.1:9093/#/alerts

[philicious]

why got alertmanager config removed entirely? (and not refactored to --alert.. back like the other configs)

[eduponte]

Good catch. The option is not supported anymore as of 2.0. I'm pushing a commit with the new way of configuring alert manager.

[eduponte]

See https://prometheus.io/docs/prometheus/2.0/migration/
in particular https://prometheus.io/docs/prometheus/2.0/migration/#alertmanager-service-discovery

[eduponte]

Back to life

http://ip172-18-0-15-b82s0rn9me9000f7h41g-9093.direct.labs.play-with-docker.com/#/alerts will show in 2m

[philicious]

hm for some reason I dont get the alert in alertmanager, only in prometheus.
tested on MacOS, Docker version 17.09.0-ce

[llitfkitfk]

@philicious tested on macOS

after 2 minutes