Initial upload

elixir/newsletter/lib/newsletter.ex

@@ -0,0 +1,28 @@
+defmodule Newsletter do
+  def read_emails(path) do
+    File.read!(path) |> String.split("\n", trim: true)
+  end
+
+  def open_log(path) do
+    File.open!(path, [:write])
+  end
+
+  def log_sent_email(pid, email) do
+    IO.puts(pid, "#{email}")
+  end
+
+  def close_log(pid) do
+    File.close(pid)
+  end
+
+  def send_newsletter(emails_path, log_path, send_fun) do
+    log = open_log(log_path)
+    read_emails(emails_path)
+    |> Enum.map(fn email ->
+      with :ok <- send_fun.(email) do
+        log_sent_email(log, email)
+      end
+    end)
+    close_log(log)
+  end
+end