A script to help installing elm packages.

elmpackager.rb

require "json"
require "net/http"
require "uri"

def download(name)
  puts "Installing " + name
  `elm package install #{name} --yes`
end

def prompt(instructions)
  resp = ""
  print instructions
  resp = $stdin.gets.chomp
  if resp == "y"
    true
  elsif resp == "n"
    false
  else
    prompt "Must type 'y' for yes or 'n' for no: "
  end
end

package = ARGV[0].downcase
yesToPrompts = ARGV.include? "--yes"

if package.nil?
  $stderr.puts "Error: no package specified"
  exit 1
end

if package.include? "start"
  if prompt "Would you like to download StartApp and related packages? "
    download "evancz/elm-effects"
    download "evancz/elm-html"
    download "evancz/elm-http"
    download "evancz/start-app"
    exit
  end
end

uri = URI.parse('http://package.elm-lang.org/all-packages?elm-package-version=0.16')
http = Net::HTTP.new(uri.host, uri.port)
request = Net::HTTP::Get.new(uri.request_uri)
response = http.request(request)

if response.code == "200"
  result = JSON.parse(response.body)
  names = result.map{|h| h["name"]}
  matches = names.select{|n| n.downcase.include? package}
  if matches.empty?
    puts "No matching packages found."
  elsif matches.length == 1
    match = matches.first
    if yesToPrompts
      download match, true
    else
      puts "Found one match: " + match
      if prompt "Do you want to install it now? (y/n) "
        download match
      else
        puts "Okay, you can download #{match} yourself."
      end
    end
  else
    puts "Multiple matching packages were found. You should install the one(s) you want."
    puts matches.map{|s| "\t"+s}
  end
else
  $stderr.puts "Error downloading package list."
end