Trying to deploy an existing app on Gigalixir and have had a bit of difficulty, but can’t find anything about how to resolve this current issue. It has no front end assets, it’s just an Absinthe GraphQL API.

This error occors:

 [error] Postgrex.Protocol (#PID<0.2308.0>) failed to connect: ** (Postgrex.Error) FATAL 53300 (too_many_connections) remaining connection slots are reserved for non-replication superuser connections

Followed by this warning:

[warn] Description: 'Authenticity is not established by certificate path validation' 

web.1  | Reason: 'Option {verify, verify_peer} and cacertfile/cacerts is missing'

I provisioned the database through the CLI as a Standard tier and set the pool size down to 2 as suggested by the troubleshooting docs for hitting the too_many_connections error.

Using Phoenix 1.6 / Elixir 1.12.3 / Erlang 24.2

config.exs:

import Config

config :evora,
  ecto_repos: [Evora.Repo],
  generators: [binary_id: true]

# Configures the endpoint
config :evora, EvoraWeb.Endpoint,
  url: [host: "localhost"],
  render_errors: [view: EvoraWeb.ErrorView, accepts: ~w(json), layout: false],
  pubsub_server: Evora.PubSub

prod.exs:

import Config

config :evora, Evora.Endpoint,
  load_from_system_env: true,
  http: [port: {:system, "PORT"}],
  server: true,
  secret_key_base: "${SECRET_KEY_BASE}",
  url: [host: "${APP_NAME}.gigalixirapp.com", port: 443],

releases.exs:

import Config
config :evora, EvoraWeb.Endpoint,
  server: true,
  http: [port: {:system, "PORT"}], # Needed for Phoenix 1.2 and 1.4. Doesn't hurt for 1.3.
  url: [host: System.get_env("APP_NAME") <> ".gigalixirapp.com", port: 443]

runtime.exs:

import Config
if config_env() == :prod do
  config :evora, Evora.Repo,
    adapter: Ecto.Adapters.Postgres,
    database: "",
    ssl: true,
    url: System.get_env("DATABASE_URL"),
    pool_size: String.to_integer(System.get_env("POOL_SIZE") || "10")

  secret_key_base =
    System.get_env("SECRET_KEY_BASE") ||
      raise """
      environment variable SECRET_KEY_BASE is missing.
      You can generate one by calling: mix phx.gen.secret
      """

  config :evora, EvoraWeb.Endpoint,
    http: [
      ip: {0, 0, 0, 0, 0, 0, 0, 0},
      port: String.to_integer(System.get_env("PORT") || "4000")
    ],
    secret_key_base: secret_key_base
end

elixir_buildpack.config

elixir_version=1.12.3
erlang_version=24.2