Ricardo García Vega bigardone

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An API search engine in Elm for Elm

Elm is a statically typed functional language that compiles to JavaScript. It's well-known for its developer experience: the compiler provides nice error messages, the package system enforces semantic versioning for all published packages and makes sure every exposed value or type has some documentation and type annotations.

Type Safe JSON Decoding in Elm

The power of a Static Typed language can seem magical at first. But the goal here is to take a tiny peak behind that curtain.

Elm's implementation of JSON parsing is type safe and how it achieves that can seem like a mystery. Even though I got the code to work, it took me a while to fully understand how it works.

I'm writing it down here for 2 reasons. To help others gain a greater understanding of Types and so I don't forget what I learned.

Word of Caution

Build Server

Go to Digital Ocean
Create new droplet
London
Ubuntu
No apps
Add SSH keys

Deploying Phoenix on Dokku

Worked 2015-09-08 for Phoenix 1.0.1 on Dokku 0.3.25.

These instructions assume you've set up Dokku. If not, go find a tutorial for that part. My notes for setting it up on Digital Ocean.

On your local machine, in the app's repo

Create a Dokku app:

	defmodule RequestCache do
	@moduledoc """
	Simple ETS-based cache.
	"""
	use GenServer

	@type t :: %{ttl: integer, invalidators: %{}}
	@type cache_key :: any
	@type cache_value :: any

	defmodule Map.Helpers do
	@moduledoc """
	Functions to transform maps
	"""

	@doc """
	Convert map string camelCase keys to underscore_keys
	"""
	def underscore_keys(nil), do: nil

	defmodule Reporter do
	def progress(last_data, file_name, {size_type, chunk_size}) do
	IO.inspect({last_data[:downloaded], "#{last_data[:rate]} MB/s", file_name, size_type, chunk_size})

	new_timestamp = :os.system_time(:milli_seconds)
	timestamp_diff = new_timestamp - last_data[:last_timestamp]

	case chunk_size do
	:unknown ->
	downloaded = 0

	module Auth0
	( AuthenticationState(..), AuthenticationError, AuthenticationResult

	, Options, defaultOpts

	, LoggedInUser, UserProfile, Token

	, showLock, showLockSignal
	, mapResult
	) where

	defmodule DBTransactions do
	use ExUnit.CaseTemplate

	setup_all do
	Ecto.Adapters.SQL.begin_test_transaction(Repo)

	on_exit fn ->
	Ecto.Adapters.SQL.rollback_test_transaction(Repo)
	end
	end

	;;; runs eslint --fix on the current file after save
	;;; alpha quality -- use at your own risk

	(defun eslint-fix-file ()
	(interactive)
	(message "eslint --fixing the file" (buffer-file-name))
	(shell-command (concat "eslint --fix " (buffer-file-name))))

	(defun eslint-fix-file-and-revert ()
	(interactive)