50 lines
1.2 KiB
Elixir
50 lines
1.2 KiB
Elixir
defmodule Pleroma.PrometheusExporter do
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@moduledoc """
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Exports metrics in Prometheus format.
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Mostly exists because of https://github.com/beam-telemetry/telemetry_metrics_prometheus_core/issues/52
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Basically we need to fetch metrics every so often, or the lib will let them pile up and eventually crash the VM.
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It also sorta acts as a cache so there is that too.
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"""
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use GenServer
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require Logger
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def start_link(_opts) do
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GenServer.start_link(__MODULE__, :ok, name: __MODULE__)
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end
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def init(_opts) do
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schedule_next()
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{:ok, ""}
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end
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defp schedule_next do
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Process.send_after(self(), :gather, 60_000)
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end
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# Scheduled function, gather metrics and schedule next run
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def handle_info(:gather, _state) do
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schedule_next()
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state = TelemetryMetricsPrometheus.Core.scrape()
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{:noreply, state}
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end
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# Trigger the call dynamically, mostly for testing
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def handle_call(:gather, _from, _state) do
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state = TelemetryMetricsPrometheus.Core.scrape()
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{:reply, state, state}
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end
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def handle_call(:show, _from, state) do
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{:reply, state, state}
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end
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def show do
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GenServer.call(__MODULE__, :show)
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end
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def gather do
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GenServer.call(__MODULE__, :gather)
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end
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end
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