Code for step 3

config/dev.exs

@@ -7,7 +7,8 @@ config :elixir_monitoring_prom, ElixirMonitoringProm.Repo,
   database: "elixir_monitoring_prom_dev",
   hostname: "postgres",
   show_sensitive_data_on_connection_error: true,
-  pool_size: 10
+  pool_size: 10,
+  types: ElixirMonitoringProm.PostgresTypes
 
 # For development, we disable any cache and enable
 # debugging and code reloading.

lib/elixir_monitoring_prom/postgres_types.ex

@@ -0,0 +1,5 @@
+Postgrex.Types.define(
+  ElixirMonitoringProm.PostgresTypes,
+  [Geo.PostGIS.Extension] ++ Ecto.Adapters.Postgres.extensions(),
+  json: Jason
+)

lib/elixir_monitoring_prom/zip_codes/zip_code.ex

@@ -0,0 +1,28 @@
+defmodule ElixirMonitoringProm.ZipCodes.ZipCode do
+  @moduledoc """
+  Schema to define zip code entries
+  """
+
+  use Ecto.Schema
+
+  import Ecto.Changeset
+
+  alias __MODULE__
+
+  schema "zip_codes" do
+    field :zip_code, :string
+    field :city, :string
+    field :state, :string
+    field :point, Geo.PostGIS.Geometry
+    field :timezone, :integer
+    field :dst, :boolean
+  end
+
+  def changeset(%ZipCode{} = zip_code, attrs \\ %{}) do
+    all_fields = [:zip_code, :city, :state, :point, :timezone, :dst]
+
+    zip_code
+    |> cast(attrs, all_fields)
+    |> validate_required(all_fields)
+  end
+end

mix.exs

@@ -42,7 +42,9 @@ defmodule ElixirMonitoringProm.MixProject do
       {:phoenix_live_reload, "~> 1.2", only: :dev},
       {:gettext, "~> 0.11"},
       {:jason, "~> 1.0"},
-      {:plug_cowboy, "~> 2.0"}
+      {:plug_cowboy, "~> 2.0"},
+      {:geo, "~> 3.1.0"},
+      {:geo_postgis, "~> 3.1.0"}
     ]
   end
 

mix.lock

@@ -7,6 +7,8 @@
   "ecto": {:hex, :ecto, "3.1.7", "fa21d06ef56cdc2fdaa62574e8c3ba34a2751d44ea34c30bc65f0728421043e5", [:mix], [{:decimal, "~> 1.6", [hex: :decimal, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: true]}], "hexpm"},
   "ecto_sql": {:hex, :ecto_sql, "3.1.6", "1e80e30d16138a729c717f73dcb938590bcdb3a4502f3012414d0cbb261045d8", [:mix], [{:db_connection, "~> 2.0", [hex: :db_connection, repo: "hexpm", optional: false]}, {:ecto, "~> 3.1.0", [hex: :ecto, repo: "hexpm", optional: false]}, {:mariaex, "~> 0.9.1", [hex: :mariaex, repo: "hexpm", optional: true]}, {:myxql, "~> 0.2.0", [hex: :myxql, repo: "hexpm", optional: true]}, {:postgrex, "~> 0.14.0 or ~> 0.15.0", [hex: :postgrex, repo: "hexpm", optional: true]}, {:telemetry, "~> 0.4.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm"},
   "file_system": {:hex, :file_system, "0.2.7", "e6f7f155970975789f26e77b8b8d8ab084c59844d8ecfaf58cbda31c494d14aa", [:mix], [], "hexpm"},
+  "geo": {:hex, :geo, "3.1.0", "727e005262430d037e870ff364e65d80ca5ca21d5ac8eddd57a1ada72c3f83b0", [:mix], [], "hexpm"},
+  "geo_postgis": {:hex, :geo_postgis, "3.1.0", "d06c8fa5fd140a52a5c9dab4ad6623a696dd7d99dd791bb361d3f94942442ff9", [:mix], [{:geo, "~> 3.1", [hex: :geo, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: true]}, {:poison, "~> 2.2 or ~> 3.0 or ~> 4.0", [hex: :poison, repo: "hexpm", optional: true]}, {:postgrex, "~> 0.14", [hex: :postgrex, repo: "hexpm", optional: false]}], "hexpm"},
   "gettext": {:hex, :gettext, "0.17.0", "abe21542c831887a2b16f4c94556db9c421ab301aee417b7c4fbde7fbdbe01ec", [:mix], [], "hexpm"},
   "jason": {:hex, :jason, "1.1.2", "b03dedea67a99223a2eaf9f1264ce37154564de899fd3d8b9a21b1a6fd64afe7", [:mix], [{:decimal, "~> 1.0", [hex: :decimal, repo: "hexpm", optional: true]}], "hexpm"},
   "mime": {:hex, :mime, "1.3.1", "30ce04ab3175b6ad0bdce0035cba77bba68b813d523d1aac73d9781b4d193cf8", [:mix], [], "hexpm"},

priv/repo/migrations/20190821020059_zip_code_table.exs

@@ -0,0 +1,58 @@
+defmodule ElixirMonitoringProm.Repo.Migrations.ZipCodeTable do
+  use Ecto.Migration
+
+  alias ElixirMonitoringProm.ZipCodes.ZipCode
+
+  def up do
+    execute("CREATE EXTENSION IF NOT EXISTS postgis")
+
+    create table(:zip_codes) do
+      add :zip_code, :string, size: 5, null: false
+      add :city, :string, null: false
+      add :state, :string, size: 2, null: false
+      add :timezone, :integer, null: false
+      add :dst, :boolean, null: false
+    end
+
+    execute("SELECT AddGeometryColumn('zip_codes', 'point', 4326, 'POINT', 2)")
+    execute("CREATE INDEX zip_code_point_index on zip_codes USING gist (point)")
+
+    create unique_index(:zip_codes, [:zip_code])
+
+    flush()
+
+    "#{__DIR__}/../wa_zip_codes.csv"
+    |> File.read!()
+    |> String.split("\n")
+    |> Enum.filter(fn line -> String.trim(line) != "" end)
+    |> Enum.map(fn csv_line ->
+      [zip, city, state, lat, long, tz, dst] =
+        csv_line
+        |> String.replace("\"", "")
+        |> String.replace("\n", "")
+        |> String.split(",")
+
+      city = String.downcase(city)
+      state = String.downcase(state)
+
+      attrs = %{
+        zip_code: zip,
+        city: city,
+        state: state,
+        point: %Geo.Point{coordinates: {long, lat}, srid: 4326},
+        timezone: String.to_integer(tz),
+        dst: (dst == "1" && true) || false
+      }
+
+      ZipCode.changeset(%ZipCode{}, attrs)
+    end)
+    |> Enum.each(fn zip_code_changeset ->
+      ElixirMonitoringProm.Repo.insert(zip_code_changeset, on_conflict: :nothing)
+    end)
+  end
+
+  def down do
+    drop(table(:zip_codes))
+    execute("DROP EXTENSION IF EXISTS postgis")
+  end
+end