defmodule Router do
use Plug.Router
use Plug.Debugger
require Logger
plug(Plug.Logger, log: :debug)
plug(Plug.Parsers, parsers: [:urlencoded])
plug(:match)
plug(:dispatch)
@usage """
Usage: Try querying some of the following endpoints...
GET /
GET /help
GET /semiprime?number=<integer>
GET /semiprimes?numbers=<comma-separated-integers>
"""
get "/" do
send_resp(conn, 200, "Welcome to Semiprimes Service!\n\n#{@usage}")
end
get "/help" do
send_resp(conn, 200, @usage)
end
get "/semiprime" do
case conn |> Map.get(:query_params) |> Map.get("number") do
nil ->
send_resp(conn, 400, "You must pass an integer as a query parameter. #{@usage}")
val ->
case Integer.parse(val) do
{n, ""} ->
send_resp(conn, 200, semiprime_response(n))
_ ->
send_resp(conn, 400, "We could not parse the number you provided.\n\n#{@usage}")
end
end
end
get "/semiprimes" do
case conn |> Map.get(:query_params) |> Map.get("numbers") do
nil ->
send_resp(
conn,
400,
"You must pass a comma-separated list of integers as a query parameter.\n\n#{@usage}"
)
xs ->
response =
xs
|> String.split(",")
|> Stream.map(&Integer.parse/1)
|> Stream.filter(fn
{n, ""} -> true
_ -> false
end)
|> Stream.map(fn {n, ""} -> semiprime_response(n) end)
|> Enum.join("\n")
send_resp(conn, 200, response)
end
end
match _ do
send_resp(conn, 404, "Not found.")
end
################################################################################
# Utils
################################################################################
defp semiprime_response(n) do
case Server.semiprime(n) do
nil ->
"#{n} is not a semiprime. Try another number!"
{hit_or_miss, factors} ->
response = "#{n} is a semiprime! Its factors are #{Enum.join(factors, " and ")}."
"Cache #{Atom.to_string(hit_or_miss)} - #{response}"
end
end
end
