This document summarizes various things that can be done with the Elixir programming language. It discusses building web applications with Phoenix, integrating with services like RethinkDB and Postgres using libraries like ex_aws and Postgrex, communicating with Java processes using ports, building HTTP and socket APIs, and running concurrent tasks. Examples are provided for web sockets, database changefeeds, notifications, HTTP requests/responses, TCP sockets, and async task streams in Elixir.

1. Александр Хохлов
@nots_io
Phoenix and beyond:
Things we do with Elixir

2. Founder at Nots.io
http://nots.io

6. Why this talk?

7. In the beginning…

8. Phoenix:
Web Sockets, HAML, SASS

9. Guardian, Arc, ex_aws, Swoosh,
ueberauth/ueberauth_github

10. RethinkDB
rethinkdb_changefeed
postgrex

11. https://github.com/h4cc/
awesome-elixir

12. http://obolinx.com/resources/?p=1837

13. Erlang/Elixir port to Java process
with JInterface

14. https://www.safaribooksonline.com/library/view/erlang-programming/9780596803940/ch16s05.html

16. def init(_params) do
cd = “#{:code.priv_dir(:your_app)}"
cmd = "java -jar package.jar"
port = Port.open({:spawn,cmd}, [:binary, :use_stdio,
packet: 4, cd: cd])
true = Port.connect(port, self())
{:ok,port}
end
Port.command(port, :erlang.term_to_binary(data))
def handle_info({port,{:data,b}}, port) do
data = :erlang.binary_to_term(b)
end

17. Postgrex.Notifications +
GenServer

19. PLPGSQL:
PERFORM pg_notify(‘invitations_changes’, payload)
Elixir:
{:ok, pid} = Postgrex.Notifications.start_link(config)
Postgrex.Notifications.listen(pid, "invitations_changes")
def handle_info({:notification, _pid, _ref,
"invitations_changes", payload}, state) do … end

21. API:
HTTP API with
Poison & HTTPoison

22. HTTPoison.put(url, Poison.encode!(data))
HTTPoison.get(url)
HTTPoison.post(url, Poison.encode!(data)))
case resp do
{:ok, %HTTPoison.Response{status_code: 200, body: body}}->
{:ok, body |> Poison.decode!}
{:ok, %HTTPoison.Response{status_code: 404}} ->
{:error, :not_found}
{:ok, %HTTPoison.Response{body: body}} ->
{:error, body |> Poison.decode!}
{:error, %HTTPoison.Error{reason: reason}} ->
{:error, reason}
end

23. API:
Socket API with gen_tcp

25. # receive tcp packet as message
{:ok, socket} = :gen_tcp.connect('localhost', port,
[:binary, active: true])
def handle_info({:tcp, _socket, msg}, state) do ...
end
# receive tcp packet with recv
:inet.setopts(socket, active: false)
:ok = :gen_tcp.send(socket, data)
{:ok, <<_msg_len :: binary - size(16),
msg :: binary>>} = :gen_tcp.recv(socket, 0, 2000)

26. Concurrent tasks

27. results = notes
|> Task.async_stream(__MODULE__, :update,
[some, params], max_concurrency: 20)
|> Enum.to_list
|> Keyword.get(:ok)
def update(note, some, params) do ... end

29. point@nots.io
http://nots.io
http://blog.nots.io
@nots_io
facebook.com/nots.io