João Paulo Dubas
34c3a3e4c2
Use prom_ex to expose system metrics to prometheus and create dashboards. Co-authored-by: Joao P Dubas <joao.dubas@gmail.com> Reviewed-on: #4
103 lines
2.9 KiB
Elixir
103 lines
2.9 KiB
Elixir
defmodule Wabanex.PromEx do
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@moduledoc """
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Be sure to add the following to finish setting up PromEx:
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1. Update your configuration (config.exs, dev.exs, prod.exs, releases.exs, etc) to
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configure the necessary bit of PromEx. Be sure to check out `PromEx.Config` for
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more details regarding configuring PromEx:
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```
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config :wabanex, Wabanex.PromEx,
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disabled: false,
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manual_metrics_start_delay: :no_delay,
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drop_metrics_groups: [],
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grafana: :disabled,
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metrics_server: :disabled
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```
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2. Add this module to your application supervision tree. It should be one of the first
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things that is started so that no Telemetry events are missed. For example, if PromEx
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is started after your Repo module, you will miss Ecto's init events and the dashboards
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will be missing some data points:
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```
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def start(_type, _args) do
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children = [
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Wabanex.PromEx,
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...
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]
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...
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end
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```
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3. Update your `endpoint.ex` file to expose your metrics (or configure a standalone
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server using the `:metrics_server` config options). Be sure to put this plug before
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your `Plug.Telemetry` entry so that you can avoid having calls to your `/metrics`
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endpoint create their own metrics and logs which can pollute your logs/metrics given
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that Prometheus will scrape at a regular interval and that can get noisy:
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```
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defmodule WabanexWeb.Endpoint do
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use Phoenix.Endpoint, otp_app: :wabanex
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...
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plug PromEx.Plug, prom_ex_module: Wabanex.PromEx
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...
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end
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```
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4. Update the list of plugins in the `plugins/0` function return list to reflect your
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application's dependencies. Also update the list of dashboards that are to be uploaded
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to Grafana in the `dashboards/0` function.
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"""
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use PromEx, otp_app: :wabanex
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alias PromEx.Plugins
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@impl true
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def plugins do
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[
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# PromEx built in plugins
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Plugins.Application,
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Plugins.Beam,
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# {Plugins.Phoenix, router: WabanexWeb.Router, endpoint: WabanexWeb.Endpoint},
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Plugins.Ecto,
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# Plugins.Oban,
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# Plugins.PhoenixLiveView,
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Plugins.Absinthe
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# Plugins.Broadway,
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# Add your own PromEx metrics plugins
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# Wabanex.Users.PromExPlugin
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]
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end
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@impl true
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def dashboard_assigns do
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[
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datasource_id: "prometheus",
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default_selected_interval: "30s"
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]
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end
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@impl true
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def dashboards do
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[
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# PromEx built in Grafana dashboards
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{:prom_ex, "application.json"},
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{:prom_ex, "beam.json"},
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# {:prom_ex, "phoenix.json"},
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{:prom_ex, "ecto.json"},
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# {:prom_ex, "oban.json"},
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# {:prom_ex, "phoenix_live_view.json"},
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{:prom_ex, "absinthe.json"}
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# {:prom_ex, "broadway.json"},
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# Add your dashboard definitions here with the format: {:otp_app, "path_in_priv"}
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# {:wabanex, "/grafana_dashboards/user_metrics.json"}
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]
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end
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end
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