DEV Community: Luis Gustavo Caciatori

TIL - Phoenix Router 1.7 --Info trick

Luis Gustavo Caciatori — Thu, 10 Aug 2023 16:10:14 +0000

For Phoenix 1.7 you can pass an option --info for a path and the mix command will return to you the controller, action and file name with line for that router.

mix phx.routes --info http://localhost:4000/status

results

$ mix phx.routes --info http://localhost:4000/status
Module: ExampleWeb.StatusController
Function: :status
/Users/lab/example/lib/example_web/controllers/status_controller.ex:7

More info https://hexdocs.pm/phoenix/1.7.7/Mix.Tasks.Phx.Routes.html

Commit for this change on Phoenix repository
https://github.com/phoenixframework/phoenix/commits/v1.7.7/lib/mix/tasks/phx.routes.ex

TIL Phoenix Live View #1

Luis Gustavo Caciatori — Mon, 24 Oct 2022 23:46:44 +0000

With Phoenix LiveView 0.18 now you can define attributes to components

attr :name, :string, required: true
# or define with default value
# attr :name, :string, default: "World"

def hello(assigns) do
  ~H"""
    <h1>Hello #{@name} </h1>
  """
end

But the most interesting part is that you can also define with a Schema or Struct, helping you with autocomplete (if your editor supports) and compile warns

attr :user, User, required: true

def hello(assigns) do
  ~H"""
    <h1>Hello #{user.name}</h1>
  """
end

You can find more information about here

TIL IEX Console #2

Luis Gustavo Caciatori — Thu, 12 May 2022 09:05:31 +0000

Quick learn for today, when you need to check the public functions from a specific module use the helper exports/1, here an example:

iex(1)> exports Enum
all?/1                all?/2                any?/1                any?/2
at/2                  at/3                  chunk/2               chunk/3
chunk/4               chunk_by/2            chunk_every/2         chunk_every/3
chunk_every/4         chunk_while/4         concat/1              concat/2
count/1               count/2               count_until/2         count_until/3
dedup/1               dedup_by/2            drop/2                drop_every/2
drop_while/2          each/2                empty?/1              fetch/2
fetch!/2              filter/2              filter_map/3          find/2
find/3                find_index/2          find_value/2          find_value/3
flat_map/2            flat_map_reduce/3     frequencies/1         frequencies_by/2
group_by/2            group_by/3            intersperse/2         into/2
into/3                join/1                join/2                map/2
map_every/3           map_intersperse/3     map_join/2            map_join/3
map_reduce/3          max/1                 max/2                 max/3
max_by/2              max_by/3              max_by/4              member?/2
min/1                 min/2                 min/3                 min_by/2
min_by/3              min_by/4              min_max/1             min_max/2
min_max_by/2          min_max_by/3          min_max_by/4          partition/2
product/1             random/1              reduce/2              reduce/3
reduce_while/3        reject/2              reverse/1             reverse/2
reverse_slice/3       scan/2                scan/3                shuffle/1
slice/2               slice/3               slide/3               sort/1
sort/2                sort_by/2             sort_by/3             split/2
split_while/2         split_with/2          sum/1                 take/2
take_every/2          take_random/2         take_while/2          to_list/1
uniq/1                uniq/2                uniq_by/2             unzip/1
with_index/1          with_index/2          zip/1                 zip/2
zip_reduce/3          zip_reduce/4          zip_with/2            zip_with/3

Also works with Erlang modules:

iex(2)> exports :io
nl/1                  columns/0             columns/1             rows/1
get_chars/2           get_chars/3           get_password/0        get_password/1
setopts/1             write/1               write/2               read/1
read/2                read/4                fwrite/1              fwrite/3
fread/2               fread/3               scan_erl_exprs/1      scan_erl_exprs/2
scan_erl_exprs/3      scan_erl_exprs/4      scan_erl_form/1       scan_erl_form/2
scan_erl_form/4       parse_erl_exprs/1     parse_erl_exprs/2     parse_erl_exprs/4
parse_erl_form/1      parse_erl_form/2      parse_erl_form/3      parse_erl_form/4
request/1             requests/1            requests/2            scan_erl_form/3
fwrite/2              getopts/1             nl/0                  rows/0
put_chars/2           setopts/2             get_line/2            parse_erl_exprs/3
read/3                request/2             getopts/0             get_line/1
put_chars/1           format/1              format/2              format/3
printable_range/0

TIL IEX Console #1

Luis Gustavo Caciatori — Wed, 04 May 2022 00:27:57 +0000

TIL a small trick on Elixir console (iex) that is the helper i/1

When you type some piece of code on iex e.g:

iex(1)> IO.inspect {:a, :b}
{:a, :b}

And after that you type i. This helper will print the type information about the last command typed on iex.

iex(1)> I
Term
  {:a, :b}
Data type
  Tuple
Reference modules
  Tuple
Implemented protocols
  IEx.Info, Inspect

You also can specify a term to the helper as on the example below.

iex(3)> i (4 / 2)
Term
  2.0
Data type
  Float
Reference modules
  Float
Implemented protocols
  IEx.Info, Inspect, List.Chars, String.Chars

iex(4)> i "hello"
Term
  "hello"
Data type
  BitString
Byte size
  5
Description
  This is a string: a UTF-8 encoded binary. It's printed surrounded by
  "double quotes" because all UTF-8 encoded code points in it are printable.
Raw representation
  <<104, 101, 108, 108, 111>>
Reference modules
  String, :binary
Implemented protocols
  Collectable, IEx.Info, Inspect, List.Chars, String.Chars

And that's it for today.