fix postal code downloader/parser

Author: mithereal

lib/location.ex

@@ -1,3 +1,4 @@
+NimbleCSV.define(PostCodeCSV, separator: ",", escape: "\~")
 NimbleCSV.define(LocationCSV, separator: "\t", escape: "\~")
 
 defmodule Location do

lib/location/postalcode.ex

@@ -23,40 +23,26 @@ defmodule Location.PostalCode do
         {:decentralized_counters, false}
       ])
 
+    @ets_table_by_id =
+      :ets.new(@ets_table_by_id, [
+        :set,
+        :named_table,
+        :public,
+        :compressed,
+        {:write_concurrency, true},
+        {:read_concurrency, true},
+        {:decentralized_counters, false}
+      ])
+
     source_file()
     |> File.stream!()
     |> Stream.chunk_every(15_000)
     |> Task.async_stream(
       fn chunk ->
         chunk
-        |> LocationCSV.parse_stream()
-        |> Stream.each(fn [
-                            country_code,
-                            postal_code,
-                            city_name,
-                            _state_name,
-                            state_code,
-                            _municipality,
-                            _municipality_code,
-                            _admin_name3,
-                            _admin_code3,
-                            latitude,
-                            longitude,
-                            _accuracy
-                          ] ->
-          country_code = String.trim(country_code)
-
-          true =
-            :ets.insert(
-              @ets_table_by_lookup,
-              {{country_code, state_code, city_name}, {postal_code, latitude, longitude}}
-            )
-
-          true =
-            :ets.insert(
-              @ets_table_by_id,
-              {postal_code, {country_code, state_code, city_name, latitude, longitude}}
-            )
+        |> PostCodeCSV.parse_stream()
+        |> Stream.each(fn data ->
+          __MODULE__.parse(data)
         end)
         |> Stream.run()
       end,
@@ -65,6 +51,125 @@ defmodule Location.PostalCode do
     |> Stream.run()
   end
 
+  def parse(data) do
+    case data do
+      [
+        country_code,
+        postal_code,
+        city_name,
+        _state_name,
+        state_code,
+        _municipality,
+        _municipality_code,
+        _admin_name3,
+        _admin_code3,
+        latitude,
+        longitude,
+        _accuracy,
+        _,
+        _
+      ] ->
+        country_code = String.trim(country_code)
+
+        true =
+          :ets.insert(
+            @ets_table_by_lookup,
+            {{country_code, state_code, city_name}, {postal_code, latitude, longitude}}
+          )
+
+        true =
+          :ets.insert(
+            @ets_table_by_id,
+            {postal_code, {country_code, state_code, city_name, latitude, longitude}}
+          )
+
+      [
+        country_code,
+        postal_code,
+        city_name,
+        _state_name,
+        state_code,
+        _municipality,
+        _municipality_code,
+        _admin_name3,
+        _admin_code3,
+        latitude,
+        longitude,
+        _accuracy,
+        _
+      ] ->
+        country_code = String.trim(country_code)
+
+        true =
+          :ets.insert(
+            @ets_table_by_lookup,
+            {{country_code, state_code, city_name}, {postal_code, latitude, longitude}}
+          )
+
+        true =
+          :ets.insert(
+            @ets_table_by_id,
+            {postal_code, {country_code, state_code, city_name, latitude, longitude}}
+          )
+
+      [
+        country_code,
+        postal_code,
+        city_name,
+        _state_name,
+        state_code,
+        _municipality,
+        _municipality_code,
+        _admin_name3,
+        _admin_code3,
+        latitude,
+        longitude,
+        _accuracy
+      ] ->
+        country_code = String.trim(country_code)
+
+        true =
+          :ets.insert(
+            @ets_table_by_lookup,
+            {{country_code, state_code, city_name}, {postal_code, latitude, longitude}}
+          )
+
+        true =
+          :ets.insert(
+            @ets_table_by_id,
+            {postal_code, {country_code, state_code, city_name, latitude, longitude}}
+          )
+
+      [
+        country_code,
+        postal_code,
+        city_name,
+        _state_name,
+        state_code,
+        _municipality,
+        _municipality_code,
+        _admin_name3,
+        _admin_code3,
+        latitude,
+        longitude
+      ] ->
+        true =
+          :ets.insert(
+            @ets_table_by_lookup,
+            {{country_code, state_code, city_name}, {postal_code, latitude, longitude}}
+          )
+
+        true =
+          :ets.insert(
+            @ets_table_by_id,
+            {postal_code, {country_code, state_code, city_name, latitude, longitude}}
+          )
+
+      _data ->
+        :ok
+    end
+  end
+
   @doc """
   Finds postal_code information by postal code.
   """
@@ -99,6 +204,15 @@ defmodule Location.PostalCode do
     end
   end
 
+  @spec get_postal_codes() :: %__MODULE__{} | nil
+  def get_postal_codes() do
+    :ets.tab2list(@ets_table_by_id)
+    |> Enum.map(fn x ->
+      {{country_code, state_code, city_name}, {postal_code, latitude, longitude}} = x
+      to_struct(postal_code, country_code, state_code, city_name, latitude, longitude)
+    end)
+  end
+
   defp source_file() do
     default = Application.app_dir(:location, "/priv/postal_codes.csv")
     Application.get_env(:location, :postal_codes_source_file, default)

lib/mix/tasks/update_geoname_data.ex

@@ -11,6 +11,7 @@ defmodule Mix.Tasks.Location.UpdateGeonameData do
     System.cmd("wget", [@allcountries_src, "-O", "/tmp/allCountries.zip"])
     zip_file = Unzip.LocalFile.open("/tmp/allCountries.zip")
     {:ok, unzip} = Unzip.new(zip_file)
+
     Unzip.file_stream!(unzip, "allCountries.txt")
     |> Stream.into(File.stream!("/tmp/allCountries.txt"))
     |> Stream.run()

lib/mix/tasks/update_postal_code_data.ex

@@ -2,7 +2,11 @@ defmodule Mix.Tasks.Location.UpdatePostalCodeData do
   use Mix.Task
   @shortdoc "Updates the postal code data from source"
 
-  @destination_filename Application.compile_env(:location, :postal_codes_source_file, "priv/postal_codes.csv")
+  @destination_filename Application.compile_env(
+                          :location,
+                          :postal_codes_source_file,
+                          "priv/postal_codes.csv"
+                        )
 
   @doc """
   The data source clocks in at 16mb. Expect this to take a while.
@@ -46,6 +50,7 @@ defmodule Mix.Tasks.Location.UpdatePostalCodeData do
 
     zip_file = Unzip.LocalFile.open("/tmp/#{name}.zip")
     {:ok, unzip} = Unzip.new(zip_file)
+
     Unzip.file_stream!(unzip, "#{name}.txt")
     |> Stream.into(File.stream!("/tmp/#{name}.txt"))
     |> Stream.run()
@@ -61,18 +66,15 @@ defmodule Mix.Tasks.Location.UpdatePostalCodeData do
       filename
       |> File.stream!(read_ahead: 100_000)
       |> Flow.from_enumerable()
-      |> Flow.map(&String.split(&1, tab))
+      |> Flow.map(&(String.trim(&1) |> String.split(tab)))
       |> Flow.partition()
       |> Enum.into([])
 
     IO.puts("Writing result to #{@destination_filename}")
 
     Location.Scraper.write_date_to_version()
 
-    case append do
-      false -> File.write!(@destination_filename, Enum.join(result, "\n"))
-      true -> File.write!(@destination_filename, Enum.join(result, "\n"), :append)
-    end
-
+    file = File.open!(@destination_filename, [:write, :utf8])
+    result |> CSV.encode() |> Enum.each(&IO.write(file, &1))
   end
 end

location.iml

@@ -77,5 +77,6 @@
     <orderEntry type="library" name="unzip" level="project" />
     <orderEntry type="library" name="benchee_html" level="project" />
     <orderEntry type="library" name="mox" level="project" />
+    <orderEntry type="library" name="csv" level="project" />
   </component>
 </module>

mix.exs

@@ -52,7 +52,8 @@ defmodule Location.MixProject do
       {:tesla, "~> 1.8"},
       {:hackney, "~> 1.20"},
       {:flow, "~> 1.2"},
-      {:unzip, "0.11.0"}
+      {:unzip, "0.11.0"},
+      {:csv, "~> 3.2"}
     ]
   end
 end

mix.lock

@@ -1,5 +1,6 @@
 %{
   "certifi": {:hex, :certifi, "2.14.0", "ed3bef654e69cde5e6c022df8070a579a79e8ba2368a00acf3d75b82d9aceeed", [:rebar3], [], "hexpm", "ea59d87ef89da429b8e905264fdec3419f84f2215bb3d81e07a18aac919026c3"},
+  "csv": {:hex, :csv, "3.2.2", "452f96414b39a176b7c390af6d8b78f15130dc6167fe3b836729131f515d843e", [:mix], [], "hexpm", "cbf256ff74a3fa01d9ec420d07b19c90d410ed9fe5b6d6e1bc7662edf35bc574"},
   "floki": {:hex, :floki, "0.35.4", "cc947b446024732c07274ac656600c5c4dc014caa1f8fb2dfff93d275b83890d", [:mix], [], "hexpm", "27fa185d3469bd8fc5947ef0f8d5c4e47f0af02eb6b070b63c868f69e3af0204"},
   "flow": {:hex, :flow, "1.2.4", "1dd58918287eb286656008777cb32714b5123d3855956f29aa141ebae456922d", [:mix], [{:gen_stage, "~> 1.0", [hex: :gen_stage, repo: "hexpm", optional: false]}], "hexpm", "874adde96368e71870f3510b91e35bc31652291858c86c0e75359cbdd35eb211"},
   "gen_stage": {:hex, :gen_stage, "1.2.1", "19d8b5e9a5996d813b8245338a28246307fd8b9c99d1237de199d21efc4c76a1", [:mix], [], "hexpm", "83e8be657fa05b992ffa6ac1e3af6d57aa50aace8f691fcf696ff02f8335b001"},