feat: fetch_input mix task

2021/.gitignore

@@ -25,3 +25,5 @@ advent_of_code-*.tar
 
 # Temporary files for e.g. tests
 /tmp
+
+.envrc

2021/config/config.exs

@@ -0,0 +1,4 @@
+import Config
+
+config :advent_of_code,
+  event: "2021"

2021/config/runtime.exs

@@ -0,0 +1,3 @@
+import Config
+
+config :advent_of_code, session: System.get_env("ADVENT_OF_CODE_SESSION")

2021/lib/advent_of_code.ex

@@ -16,6 +16,8 @@ defmodule AdventOfCode do
     Module.concat(AdventOfCode, Macro.camelize("Day#{day_number(day)}"))
   end
 
+  def day_input_path(day), do: "priv/inputs/#{day_number(day)}.input"
+
   defp day_number(day), do: String.pad_leading(day, 2, "0")
   defp part_number(part), do: String.trim_leading(part, "0")
 end

2021/lib/mix/advent_of_code.ex

@@ -5,4 +5,5 @@ defmodule Mix.AdventOfCode do
 
   defdelegate day_module(day), to: AdventOfCode
   defdelegate part_module(day, part), to: AdventOfCode
+  defdelegate day_input_path(day), to: AdventOfCode
 end

2021/lib/mix/tasks/advent_of_code.fetch_input.ex

@@ -0,0 +1,54 @@
+defmodule Mix.Tasks.AdventOfCode.FetchInput do
+  use Mix.Task
+
+  import Mix.Generator
+  import Mix.AdventOfCode
+
+  @shortdoc "Fetches the inputs for day and saves them in `priv/inputs`"
+
+  @moduledoc """
+  #{@shortdoc}.
+
+  ## Examples
+
+      # Fetch day 1's inputs
+      $ mix advent_of_code.fetch_input 1
+  """
+
+  @finch Mix.AdventOfCode.FetchInput.Finch
+
+  @switches [event: :string, session: :string]
+
+  @impl Mix.Task
+  def run(args) do
+    Mix.Task.run("app.config")
+    :ok = Application.ensure_started(:telemetry)
+    {:ok, _pid} = Finch.start_link(name: @finch)
+
+    default_event = Application.get_env(:advent_of_code, :event)
+    default_session = Application.get_env(:advent_of_code, :session)
+
+    case OptionParser.parse!(args, strict: @switches) do
+      {opts, [day]} ->
+        input_file_path = day_input_path(day)
+
+        if overwrite?(input_file_path) do
+          event = Keyword.get(opts, :event, default_event)
+          session = Keyword.get(opts, :session, default_session)
+
+          {:ok, %{body: data}} =
+            Finch.build(
+              :get,
+              "https://adventofcode.com/#{event}/day/#{day}/input",
+              [{"Cookie", "session=#{session}"}]
+            )
+            |> Finch.request(@finch)
+
+          create_file(input_file_path, data, force: true)
+        end
+
+      _ ->
+        Mix.raise("Unexpected arguments.")
+    end
+  end
+end

2021/mix.exs

@@ -25,6 +25,7 @@ defmodule AdventOfCode.MixProject do
   # Run "mix help deps" to learn about dependencies.
   defp deps do
     [
+      {:finch, "~> 0.9.0"},
       {:progress_bar, "~> 2.0"}
     ]
   end

2021/mix.lock

@@ -1,4 +1,10 @@
 %{
+  "castore": {:hex, :castore, "0.1.13", "ccf3ab251ffaebc4319f41d788ce59a6ab3f42b6c27e598ad838ffecee0b04f9", [:mix], [], "hexpm", "a14a7eecfec7e20385493dbb92b0d12c5d77ecfd6307de10102d58c94e8c49c0"},
   "decimal": {:hex, :decimal, "2.0.0", "a78296e617b0f5dd4c6caf57c714431347912ffb1d0842e998e9792b5642d697", [:mix], [], "hexpm", "34666e9c55dea81013e77d9d87370fe6cb6291d1ef32f46a1600230b1d44f577"},
+  "finch": {:hex, :finch, "0.9.0", "8b772324aebafcaba763f1dffaa3e7f52f8c4e52485f50f48bbb2f42219a2e87", [:mix], [{:castore, "~> 0.1", [hex: :castore, repo: "hexpm", optional: false]}, {:mint, "~> 1.3", [hex: :mint, repo: "hexpm", optional: false]}, {:nimble_options, "~> 0.3.5", [hex: :nimble_options, repo: "hexpm", optional: false]}, {:nimble_pool, "~> 0.2", [hex: :nimble_pool, repo: "hexpm", optional: false]}, {:telemetry, "~> 0.4 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "a93bfcad9ca50fa3cb2d459f27667d9a87cfbb7fecf9b29b2e78a50bc2ab445d"},
+  "mint": {:hex, :mint, "1.4.0", "cd7d2451b201fc8e4a8fd86257fb3878d9e3752899eb67b0c5b25b180bde1212", [:mix], [{:castore, "~> 0.1.0", [hex: :castore, repo: "hexpm", optional: true]}], "hexpm", "10a99e144b815cbf8522dccbc8199d15802440fc7a64d67b6853adb6fa170217"},
+  "nimble_options": {:hex, :nimble_options, "0.3.7", "1e52dd7673d36138b1a5dede183b5d86dff175dc46d104a8e98e396b85b04670", [:mix], [], "hexpm", "2086907e6665c6b6579be54ef5001928df5231f355f71ed258f80a55e9f63633"},
+  "nimble_pool": {:hex, :nimble_pool, "0.2.4", "1db8e9f8a53d967d595e0b32a17030cdb6c0dc4a451b8ac787bf601d3f7704c3", [:mix], [], "hexpm", "367e8071e137b787764e6a9992ccb57b276dc2282535f767a07d881951ebeac6"},
   "progress_bar": {:hex, :progress_bar, "2.0.1", "7b40200112ae533d5adceb80ff75fbe66dc753bca5f6c55c073bfc122d71896d", [:mix], [{:decimal, "~> 2.0", [hex: :decimal, repo: "hexpm", optional: false]}], "hexpm", "2519eb58a2f149a3a094e729378256d8cb6d96a259ec94841bd69fdc71f18f87"},
+  "telemetry": {:hex, :telemetry, "1.0.0", "0f453a102cdf13d506b7c0ab158324c337c41f1cc7548f0bc0e130bbf0ae9452", [:rebar3], [], "hexpm", "73bc09fa59b4a0284efb4624335583c528e07ec9ae76aca96ea0673850aec57a"},
 }