Update to use Elixir DateTime module with time zone suppport

.github/workflows/main.yml

@@ -0,0 +1,42 @@
+name: Elixir CI
+
+on:
+ push:
+ branches: [master]
+ pull_request:
+ branches: [master]
+
+env:
+ MIX_ENV: test
+
+permissions:
+ contents: read
+
+jobs:
+ build:
+ name: Build and test
+ runs-on: ubuntu-latest
+
+ strategy:
+ matrix:
+ elixir: ['1.14.5', '1.15.4']
+ erlang: ['24.3', '25.3', '26.0']
+
+ steps:
+ - uses: actions/checkout@v3
+ - name: Set up Elixir
+ uses: erlef/setup-beam@v1
+ with:
+ version-type: 'loose'
+ elixir-version: ${{ matrix.elixir }}
+ otp-version: ${{ matrix.erlang }}
+ - name: Restore dependencies cache
+ uses: actions/cache@v2
+ with:
+ path: deps
+ key: ${{ runner.os }}-${{ matrix.erlang }}-${{ matrix.elixir }}-mix-${{ hashFiles('**/mix.lock') }}
+ restore-keys: ${{ runner.os }}-${{ matrix.erlang }}-${{ matrix.elixir }}-mix-
+ - name: Install dependencies
+ run: mix deps.get
+ - name: Run tests
+ run: mix test

CHANGELOG.md

@@ -1,5 +1,10 @@
 # Changelog
 
+## Master
+
+* Add DateTime and time zone support to date parsing/rendering
+* Fix compile warnings
+
 ## 0.2.3 2021-06-28
 
 * Add support for incorrect case in date parsing https://github.com/DockYard/elixir-mail/pull/132

README.md

@@ -1,4 +1,6 @@
-# Mail [![Build Status](https://secure.travis-ci.org/DockYard/elixir-mail.svg?branch=master)](https://travis-ci.org/DockYard/elixir-mail)
+# Mail
+
+![Build Status](https://github.com/DockYard/elixir-mail/actions/workflows/main.yml/badge.svg)
 
 An RFC2822 implementation in Elixir, built for composability.
 

lib/mail/parsers/rfc_2822.ex

@@ -41,131 +41,189 @@ defmodule Mail.Parsers.RFC2822 do
  do: extract_headers(tail, [header | headers])
 
  @doc """
- Parses a RFC2822 timestamp to an Erlang timestamp
+ Parses a RFC2822 timestamp to a DateTime with timezone
 
  [RFC2822 3.3 - Date and Time Specification](https://tools.ietf.org/html/rfc2822#section-3.3)
-
- Timezone information is ignored
  """
- def erl_from_timestamp(<<" ", rest::binary>>), do: erl_from_timestamp(rest)
- def erl_from_timestamp(<<"\t", rest::binary>>), do: erl_from_timestamp(rest)
-
- def erl_from_timestamp(<<_day::binary-size(3), ", ", rest::binary>>) do
- erl_from_timestamp(rest)
- end
+ def to_datetime(<<" ", rest::binary>>), do: to_datetime(rest)
+ def to_datetime(<<"\t", rest::binary>>), do: to_datetime(rest)
+ def to_datetime(<<_day::binary-size(3), ", ", rest::binary>>), do: to_datetime(rest)
 
- def erl_from_timestamp(<<date::binary-size(1), " ", rest::binary>>) do
- erl_from_timestamp("0" <> date <> " " <> rest)
- end
+ def to_datetime(<<date::binary-size(1), " ", rest::binary>>),
+ do: to_datetime("0" <> date <> " " <> rest)
 
  # This caters for an invalid date with no 0 before the hour, e.g. 5:21:43 instead of 05:21:43
- def erl_from_timestamp(<<date::binary-size(11), " ", hour::binary-size(1), ":", rest::binary>>) do
- erl_from_timestamp("#{date} 0#{hour}:#{rest}")
+ def to_datetime(<<date::binary-size(11), " ", hour::binary-size(1), ":", rest::binary>>) do
+ to_datetime("#{date} 0#{hour}:#{rest}")
  end
 
  # This caters for an invalid date with dashes between the date/month/year parts
- def erl_from_timestamp(
+ def to_datetime(
  <<date::binary-size(2), "-", month::binary-size(3), "-", year::binary-size(4),
  rest::binary>>
  ) do
- erl_from_timestamp("#{date} #{month} #{year}#{rest}")
+ to_datetime("#{date} #{month} #{year}#{rest}")
  end
 
- def erl_from_timestamp(
+ # This caters for an invalid two-digit year
+ def to_datetime(
+ <<date::binary-size(2), " ", month::binary-size(3), " ", year::binary-size(2), " ",
+ rest::binary>>
+ ) do
+ year = year |> String.to_integer() |> to_four_digit_year()
+ to_datetime("#{date} #{month} #{year} #{rest}")
+ end
+
+ # This caters for missing seconds
+ def to_datetime(
  <<date::binary-size(11), " ", hour::binary-size(2), ":", minute::binary-size(2), " ",
  rest::binary>>
  ) do
- erl_from_timestamp("#{date} #{hour}:#{minute}:00 #{rest}")
+ to_datetime("#{date} #{hour}:#{minute}:00 #{rest}")
  end
 
- def erl_from_timestamp(
+ # Fixes invalid value: Wed, 14 10 2015 12:34:17
+ def to_datetime(
+ <<date::binary-size(2), " ", month_digits::binary-size(2), " ", year::binary-size(4), " ",
+ hour::binary-size(2), ":", minute::binary-size(2), ":", second::binary-size(2),
+ rest::binary>>
+ ) do
+ month_name = get_month_name(month_digits)
+ to_datetime("#{date} #{month_name} #{year} #{hour}:#{minute}:#{second}#{rest}")
+ end
+
+ def to_datetime(
  <<date::binary-size(2), " ", month::binary-size(3), " ", year::binary-size(4), " ",
  hour::binary-size(2), ":", minute::binary-size(2), ":", second::binary-size(2), " ",
- _timezone::binary-size(5), _rest::binary>>
+ time_zone::binary>>
  ) do
  year = year |> String.to_integer()
- month_name = String.downcase(month)
- month = Enum.find_index(@months, &(&1 == month_name)) + 1
+ month = get_month(String.downcase(month))
  date = date |> String.to_integer()
 
  hour = hour |> String.to_integer()
  minute = minute |> String.to_integer()
  second = second |> String.to_integer()
 
- {{year, month, date}, {hour, minute, second}}
- end
+ time_zone = parse_time_zone(time_zone)
 
- def erl_from_timestamp(
-  <<date::binary-size(2), " ", month::binary-size(3), " ", year::binary-size(4), " ",
- hour::binary-size(2), ":", minute::binary-size(2), ":", second::binary-size(2)>>
-  ) do
- erl_from_timestamp("#{date} #{month} #{year} #{hour}:#{minute}:#{second} (+00:00)")
+  date_string =
+ "#{year}-#{date_pad(month)}-#{date_pad(date)}T#{date_pad(hour)}:#{date_pad(minute)}:#{date_pad(second)}#{time_zone}"
+
+ {:ok, datetime, _offset} = DateTime.from_iso8601(date_string)
+ datetime
  end
 
  # This adds support for a now obsolete format
  # https://tools.ietf.org/html/rfc2822#section-4.3
- def erl_from_timestamp(
+ def to_datetime(
  <<date::binary-size(2), " ", month::binary-size(3), " ", year::binary-size(4), " ",
  hour::binary-size(2), ":", minute::binary-size(2), ":", second::binary-size(2), " ",
  timezone::binary-size(3), _rest::binary>>
  ) do
- erl_from_timestamp("#{date} #{month} #{year} #{hour}:#{minute}:#{second} (#{timezone})")
- end
-
- # This adds support for a now obsolete format (with obsolete timezone, UT)
- # https://tools.ietf.org/html/rfc2822#section-4.3
- def erl_from_timestamp(
- <<date::binary-size(2), " ", month::binary-size(3), " ", year::binary-size(4), " ",
- hour::binary-size(2), ":", minute::binary-size(2), ":", second::binary-size(2), " ",
- "UT", _rest::binary>>
- ) do
- erl_from_timestamp("#{date} #{month} #{year} #{hour}:#{minute}:#{second} (+00:00)")
+ to_datetime("#{date} #{month} #{year} #{hour}:#{minute}:#{second} (#{timezone})")
  end
 
  # Fixes invalid value: Tue Aug 8 12:05:31 CAT 2017
- def erl_from_timestamp(
+ def to_datetime(
  <<_day::binary-size(3), " ", month::binary-size(3), " ", date::binary-size(2), " ",
  hour::binary-size(2), ":", minute::binary-size(2), ":", second::binary-size(2), " ",
  _tz::binary-size(3), " ", year::binary-size(4), _rest::binary>>
  ) do
- erl_from_timestamp("#{date} #{month} #{year} #{hour}:#{minute}:#{second} (+00:00)")
+ to_datetime("#{date} #{month} #{year} #{hour}:#{minute}:#{second}")
  end
 
  # Fixes invalid value with milliseconds Tue, 20 Jun 2017 09:44:58.568 +0000 (UTC)
- def erl_from_timestamp(
+ def to_datetime(
  <<date::binary-size(2), " ", month::binary-size(3), " ", year::binary-size(4), " ",
  hour::binary-size(2), ":", minute::binary-size(2), ":", second::binary-size(2), ".",
  _milliseconds::binary-size(3), rest::binary>>
  ) do
- erl_from_timestamp("#{date} #{month} #{year} #{hour}:#{minute}:#{second}#{rest}}")
+ to_datetime("#{date} #{month} #{year} #{hour}:#{minute}:#{second}#{rest}}")
  end
 
  # Fixes invalid value: Tue May 30 15:29:15 2017
- def erl_from_timestamp(
+ def to_datetime(
  <<_day::binary-size(3), " ", month::binary-size(3), " ", date::binary-size(2), " ",
  hour::binary-size(2), ":", minute::binary-size(2), ":", second::binary-size(2), " ",
  year::binary-size(4), _rest::binary>>
  ) do
- erl_from_timestamp("#{date} #{month} #{year} #{hour}:#{minute}:#{second} (+00:00)")
+ to_datetime("#{date} #{month} #{year} #{hour}:#{minute}:#{second} +0000")
  end
 
  # Fixes invalid value: Tue Aug 8 12:05:31 2017
- def erl_from_timestamp(
+ def to_datetime(
  <<_day::binary-size(3), " ", month::binary-size(3), " ", date::binary-size(1), " ",
  hour::binary-size(2), ":", minute::binary-size(2), ":", second::binary-size(2), " ",
  year::binary-size(4), _rest::binary>>
  ) do
- erl_from_timestamp("#{date} #{month} #{year} #{hour}:#{minute}:#{second} (+00:00)")
+ to_datetime("#{date} #{month} #{year} #{hour}:#{minute}:#{second} +0000")
  end
 
- # Fixes invalid value: Wed, 14 10 2015 12:34:17
- def erl_from_timestamp(
- <<date::binary-size(2), " ", month_digits::binary-size(2), " ", year::binary-size(4), " ",
- hour::binary-size(2), ":", minute::binary-size(2), ":", second::binary-size(2),
- rest::binary>>
+ # Fixes missing time zone
+ def to_datetime(
+ <<date::binary-size(2), " ", month::binary-size(3), " ", year::binary-size(4), " ",
+ hour::binary-size(2), ":", minute::binary-size(2), ":", second::binary-size(2)>>
  ) do
- month_name = get_month_name(month_digits)
- erl_from_timestamp("#{date} #{month_name} #{year} #{hour}:#{minute}:#{second}#{rest}")
+ to_datetime("#{date} #{month} #{year} #{hour}:#{minute}:#{second} +0000")
+ end
+
+ # # Fixes invalid value: Wed, 14 10 2015 12:34:17
+ # def to_datetime(
+ # <<date::binary-size(2), " ", month_digits::binary-size(2), " ", year::binary-size(4), " ",
+ # hour::binary-size(2), ":", minute::binary-size(2), ":", second::binary-size(2),
+ # rest::binary>>
+ # ) do
+ # month_name = get_month_name(month_digits)
+ # to_datetime("#{date} #{month_name} #{year} #{hour}:#{minute}:#{second}#{rest}")
+ # end
+
+ defp to_four_digit_year(year) when year >= 0 and year < 50, do: 2000 + year
+ defp to_four_digit_year(year) when year < 100 and year >= 50, do: 1900 + year
+
+ defp date_pad(number) when number < 10, do: "0" <> Integer.to_string(number)
+ defp date_pad(number), do: Integer.to_string(number)
+
+ defp parse_time_zone(<<"(", time_zone::binary>>) do
+ time_zone
+ |> String.trim_trailing(")")
+ |> parse_time_zone()
+ end
+
+ @months
+ |> Enum.with_index(1)
+ |> Enum.each(fn {month_name, month_number} ->
+ defp get_month(unquote(month_name)), do: unquote(month_number)
+
+ defp get_month_name(unquote(String.pad_leading(to_string(month_number), 2, "0"))),
+ do: unquote(month_name)
+ end)
+
+ # Greenwich Mean Time
+ defp parse_time_zone("GMT"), do: "+0000"
+ # Universal Time
+ defp parse_time_zone("UTC"), do: "+0000"
+ defp parse_time_zone("UT"), do: "+0000"
+
+ # US
+ defp parse_time_zone("EDT"), do: "-0400"
+ defp parse_time_zone("EST"), do: "-0500"
+ defp parse_time_zone("CDT"), do: "-0500"
+ defp parse_time_zone("CST"), do: "-0600"
+ defp parse_time_zone("MDT"), do: "-0600"
+ defp parse_time_zone("MST"), do: "-0700"
+ defp parse_time_zone("PDT"), do: "-0700"
+ defp parse_time_zone("PST"), do: "-0800"
+ # Military A-Z
+ defp parse_time_zone(<<_zone_letter::binary-size(1)>>), do: "-0000"
+
+ defp parse_time_zone(<<"+", offset::binary-size(4), _rest::binary>>), do: "+#{offset}"
+ defp parse_time_zone(<<"-", offset::binary-size(4), _rest::binary>>), do: "-#{offset}"
+
+ defp parse_time_zone(time_zone) do
+ time_zone
+ |> String.trim_leading("(")
+ |> String.trim_trailing(")")
  end
 
  @doc """
@@ -194,13 +252,6 @@ defmodule Mail.Parsers.RFC2822 do
  end)
  end
 
- @months
- |> Enum.with_index(1)
- |> Enum.each(fn {month_name, number} ->
- defp get_month_name(unquote(String.pad_leading(to_string(number), 2, "0"))),
- do: unquote(month_name)
- end)
-
  defp parse_headers(message, []), do: message
 
  defp parse_headers(message, [header | tail]) do
@@ -250,7 +301,7 @@ defmodule Mail.Parsers.RFC2822 do
  |> List.first()
 
  defp parse_header_value("Date", timestamp),
- do: erl_from_timestamp(timestamp)
+ do: to_datetime(timestamp)
 
  defp parse_header_value("Received", value),
  do: parse_received_value(value)
@@ -350,7 +401,7 @@ defmodule Mail.Parsers.RFC2822 do
  {date, comment} -> {"#{value} #{comment}", date}
  end
 
- [value, {"date", erl_from_timestamp(remove_excess_whitespace(date))}]
+ [value, {"date", to_datetime(remove_excess_whitespace(date))}]
 
  value ->
  value