Merge branch 'main' of https://git.zeitschlag.net/zeitschlag/elixir-book

this is the preferred approach according to the book

issues/config/config.exs

@@ -1,3 +1,5 @@
 use Mix.Config
 
 config :issues, github_url: "https://api.github.com"
+
+config :logger, compile_time_purge_level: :info

issues/lib/issues/cli.ex

@@ -1,4 +1,7 @@
 defmodule Issues.CLI do
+  
+  import Issues.TableFormatter, only: [print_table_for_columns: 2]
+  
   @default_count 4
 
   @moduledoc """
@@ -54,7 +57,7 @@ defmodule Issues.CLI do
     |> decode_response()
     |> sort_into_descending_order
     |> last(count)
-    |> show_issues_as_table
+    |> show_issues_as_table # alternative: print_table_for_columns(["id", "created_at", "title"])
   end
 
   def decode_response({:ok, body}), do: body
@@ -100,12 +103,12 @@ defmodule Issues.CLI do
 
     # print the title
     IO.puts(
-      "#{String.pad_trailing("#id", id_column_width)} | #{String.pad_trailing("created_at", creation_date_width)} | #{String.pad_trailing("title", title_length)} "
+      "#{String.pad_trailing("#id", id_column_width)} | #{String.pad_trailing("created_at", creation_date_width)} | #{String.pad_trailing("title", title_length)}"
     )
 
     # print seperator
     IO.puts(
-      "#{String.pad_trailing("-", id_column_width, "-")}-+-#{String.pad_trailing("-", creation_date_width, "-")}-+-#{String.pad_trailing("-", title_length, "-")}-"
+      "#{String.duplicate("-", id_column_width)}-+-#{String.duplicate("-", creation_date_width)}-+-#{String.duplicate("-", title_length)}"
     )
 
     # print each issue

issues/lib/issues/github_issues.ex

@@ -1,10 +1,14 @@
 defmodule Issues.GithubIssues do
+
+  require Logger
   
   @user_agent [ { "User-agent", "Elixir dave@pragprog.com" } ]
   # use a module attribute to fetch the value at compile time
   @github_url Application.get_env(:issues, :github_url)
   
   def fetch(user, project) do
+    Logger.info("Fetching #{user}'s project #{project}")
+
     issues_url(user, project)
     |> HTTPoison.get(@user_agent)
     |> handle_response 
@@ -15,6 +19,8 @@ defmodule Issues.GithubIssues do
   end
 
   def handle_response( {:ok, %{status_code: status_code, body: body}} ) do
+    Logger.info("Got response: status code=#{status_code}")
+    Logger.debug(fn -> inspect(body) end)
     {
       status_code |> check_for_error(),
       body |> Poison.Parser.parse!()

issues/lib/issues/table_formatter.ex

@@ -0,0 +1,45 @@
+defmodule Issues.TableFormatter do
+  import Enum, only: [each: 2, map: 2, map_join: 3, max: 1]
+
+  def print_table_for_columns(rows, headers) do
+    with data_by_columns = split_into_columns(rows, headers),
+         column_widths = widths_of(data_by_columns),
+         format = format_for(column_widths) do
+      puts_one_line_in_columns(headers, format)
+      IO.puts(separator(column_widths))
+      puts_in_columns(data_by_columns, format)
+    end
+  end
+
+  def split_into_columns(rows, headers) do
+    for header <- headers do
+      for row <- rows, do: printable(row[header])
+    end
+  end
+
+  def printable(str) when is_binary(str), do: str
+  def printable(str), do: to_string(str)
+
+  def widths_of(columns) do
+    for column <- columns, do: column |> map(&String.length/1) |> max
+  end
+
+  def format_for(columns_width) do
+    map_join(columns_width, " | ", fn width -> "~-#{width}s" end) <> "~n"
+  end
+
+  def separator(column_widths) do
+    map_join(column_widths, "-+-", fn width -> List.duplicate("-", width) end)
+  end
+
+  def puts_in_columns(data_by_columns, format) do
+    data_by_columns
+    |> List.zip()
+    |> map(&Tuple.to_list/1)
+    |> each(&puts_one_line_in_columns(&1, format))
+  end
+
+  def puts_one_line_in_columns(fields, format) do
+    :io.format(format, fields)
+  end
+end

issues/mix.exs

@@ -4,10 +4,13 @@ defmodule Issues.MixProject do
   def project do
     [
       app: :issues,
+      escript: escript_config(),
       version: "0.1.0",
       elixir: "~> 1.12",
       start_permanent: Mix.env() == :prod,
-      deps: deps()
+      deps: deps(),
+      name: "Issues",
+      source_url: "https://git.zeitschlag.net/zeitschlag/elixir-book",
     ]
   end
 
@@ -23,8 +26,17 @@ defmodule Issues.MixProject do
     [
       {:httpoison, "~> 1.8.0"},
       {:poison, "~> 5.0"},
+      {:ex_doc, "~> 0.28"},
+      {:earmark, "~> 1.4.18"},
+
       # {:dep_from_hexpm, "~> 0.3.0"},
       # {:dep_from_git, git: "https://github.com/elixir-lang/my_dep.git", tag: "0.1.0"}
     ]
   end
+
+  defp escript_config do
+    [
+      main_module: Issues.CLI
+    ]
+  end
 end