imranismail

Elixir Tips and Tricks That You Might Not Know Of

SaaS/Multitenant Migrations with Ecto

defmodule App.Team do
  use App, :schema

  ...

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function new = () => ({
  _struct: "Conn",
  host: null,
  path: null,
  port: null,
  scheme: null,
  params: {},
  requestHeaders: [],
  responseHeaders: [],
  responseBody: {},

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defmodule Queue do
  def insert(queue, item), do: :queue.in(item, queue)

  def insert_last(queue, item), do: :queue.in_r(item, queue)

  def member?(queue, item), do: :queue.member(item, queue)

  def filter(queue, fun), do: :queue.filter(fun, queue)

  def split(queue, n) do

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# Elixir :queue wrapper with modified behavior for empty queues to mimic Enumerable module in Elixir
defmodule Queue do
  def insert(queue, item), do: :queue.in(item, queue)

  def insert_last(queue, item), do: :queue.in_r(item, queue)

  def member?(queue, item), do: :queue.member(item, queue)

  def filter(queue, fun), do: :queue.filter(fun, queue)

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Attach Block Storage

Attach block storage to droplet.

50G for starters

Configure Volume

sudo mkfs.ext4 -F /dev/disk/by-id/ sudo mkdir -p /mnt/; sudo mount -o discard,defaults /dev/disk/by-id/ /mnt/; echo /dev/disk/by-id/ /mnt/ ext4 defaults,nofail,discard 0 0 | sudo tee -a /etc/fstab

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Using React with Phoenix

Create a component renderer helper and pass props as [data-props=""]

defmodule Web.ComponentHelpers do
  import Phoenix.HTML.Tag, only: [content_tag: 3]

  def component(name, props \\ %{})
  def component(name, props) when is_list(props),
    do: component(name, Enum.into(props, %{}))

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defmodule Aggregate do
  defmacro replay(struct, aggregate, do: block) do
    quote bind_quoted: [struct: struct] do
      @events [struct|@events]
      def __replay__(struct, unquote(aggregate)), do: unquote(block)
    end
  end
end

defmodule User do

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Keybase proof

I hereby claim:

• I am imranismail on github.
• I am imranismail (https://keybase.io/imranismail) on keybase.
• I have a public key ASDxoGttt5zk2ozJKng_1DUiRYjeAxoakXYHWFE_bsoObwo

To claim this, I am signing this object:

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defmodule BinaryGap do
  def max(number) when is_number(number) do
    number
    |> Integer.to_string(2)
    |> calculate()
  end

  defp calculate(binary, count \\ -1, max \\ 0)
  defp calculate("1" <> remaining, count, max) do
    calculate(remaining, 0, Enum.max([max, count]))

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defmodule App.ChangesetView do
  use App, :view

  @doc """
  Traverses and translates changeset errors.
  See `Ecto.Changeset.traverse_errors/2`
  """
  def translate_errors(changeset) do
    Ecto.Changeset.traverse_errors(changeset, &translate_error/1)
  end