aries/aries/lib/aries.rb

# frozen_string_literal: true
require_relative "aries/version"
require_relative "aries/database"

require "json"
require "socket"
# require "profile"

module Aries
  class Error < StandardError; end
  # Your code goes here...

  def self.action callable
    begin
      [callable.call, nil]
    rescue => e
      pp e.backtrace << e
      [nil, e]
    end
  end

  def self.valid? commands
    for command in commands
      command.keys.each do |k|
        if ! ["add", "find", "first", "last"].include? k
          return [nil, "Undefined command key '#{k}'"]
        end
      end
    end

    return [true, nil]
  end

  host   = "localhost"
  port   = 1234
  server = TCPServer.new host, port
    
  puts "Server started, listening #{host}:#{port}"

  dbs = {}
  db_factory = lambda do |n|
    if ! dbs.keys.include? n
      dbs[n] = Database.new n
      puts "Initialized database #{n}"
    end

    dbs[n]
  end

  # ticker thread
  Thread.new do
    limit = 60 * 10
    loop do
      dbs.keys.each do |n|
        db = dbs[n]
        if db.used_at and ((db.used_at.to_i + limit) < Time.now.to_i)
          puts "Closing database #{n} it was last used more than #{limit} seconds ago"
          dbs.delete n
          puts "Closed database #{n}"
        end
      end
      sleep 1
    end
  end

  loop do
    Thread.start server.accept do |client|
      # client = server.accept
    
      connection = JSON.parse(client.gets)
      db = db_factory.call connection['database']

      # client.puts "Connected to Aries"
      puts "Client connected #{client}"

      while commands = client.gets
        commands, err = action -> { JSON.parse commands }
        
        if ! err.nil?
          client.puts JSON.generate(err: err)
          next
        end

        _, err = valid? commands

        if ! err.nil?
          client.puts JSON.generate(err: err)
          next
        end

        results = {}
        commands.each_with_index do |command, idx|
        
          func, vals = command.to_a.first
          begin
            results[idx] = db.send(func, vals)
            db.used_at = Time.now.to_i
          rescue => e
            pp [e.backtrace << e]
            results = {err: e}
            break
          end
        end

        client.puts JSON.generate(results)
      end

      client.close
      puts "Client disconnected #{client}"
    end
  end

end