first commit

app.rb

@@ -0,0 +1,331 @@
+require "bundler/setup"
+require "sinatra"
+require "sinatra/json"
+require "sinatra/cookies"
+require "time"
+require "fileutils"
+require "json"
+
+require "securerandom"
+require "random/formatter"
+require "ulid"
+require "anyflake"
+
+require "jwt"
+
+SESSION_SECRET_HEX_LENGTH = 64
+
+set :session_secret, ENV.fetch('SESSION_SECRET') { SecureRandom.hex(SESSION_SECRET_HEX_LENGTH) }
+
+CLK_TCK = 100
+PID_FILE_PATH = "/run/pid".freeze
+PROC_UPTIME_PATH = "/proc/uptime".freeze
+
+SECONDS_PER_YEAR = 31_556_952
+SECONDS_PER_MINUTE = 60
+SECONDS_PER_HOUR = 3_600
+SECONDS_PER_DAY = 86_400
+SECONDS_PER_WEEK = 604_800
+SECONDS_PER_MONTH = SECONDS_PER_YEAR / 12
+
+DURATION_PARTS = [
+  [SECONDS_PER_YEAR, "year", "y"],
+  [SECONDS_PER_MONTH, "month", "m"],
+  [SECONDS_PER_WEEK, "week", "w"],
+  [SECONDS_PER_DAY, "day", "d"],
+  [SECONDS_PER_HOUR, "hour", "h"],
+  [SECONDS_PER_MINUTE, "minute", "m"],
+  [1, "second", "s"],
+].freeze
+
+JWT_SECRET = SecureRandom.bytes(64).freeze
+
+module Sinatra
+  module RequestHeadersHelper
+    def req_headers
+      hash = request.env.select { |k, _| k.start_with? "HTTP_" }
+                    .collect { |k, v| [k.gsub(/^HTTP_/, "").gsub(/_/, "-").downcase, v] }
+                    .sort
+      h = Rack::Headers.new
+      h.merge hash
+    end
+  end
+
+  helpers RequestHeadersHelper
+end
+
+module State
+  def enable
+    FileUtils.touch(@file)
+  end
+
+  def disable
+    File.delete @file if File.file? @file
+  end
+
+  def enabled?
+    File.file? @file
+  end
+
+  def toggle
+    return enable unless enabled?
+
+    disable
+  end
+end
+
+module UpDown
+  def up
+    enable
+  end
+
+  def down
+    disable
+  end
+
+  def to_s
+    enabled? ? "up" : "down"
+  end
+
+  def to_json(*_args)
+    return unless enabled?
+
+    JSON.generate({ "status" => "ok" })
+  end
+end
+
+class TickTock
+  def initialize
+    @pid = master_pid
+    @procfs_f = format "/proc/%s/stat", @pid
+    puts @pid
+  end
+
+  def uptime
+    x = ""
+    File.open @procfs_f do |f|
+      f.each_line do |l|
+        x = l.strip.split
+      end
+    end
+    system_uptime - (Integer(x[21]) / CLK_TCK)
+  end
+
+  def started_at
+    Time.now - uptime
+  end
+end
+
+class Health
+  include Singleton
+  include State
+  include UpDown
+
+  def initialize
+    @file = "./healthy"
+  end
+
+  def healthy?
+    enabled?
+  end
+end
+
+class Ready
+  include Singleton
+  include State
+  include UpDown
+
+  def initialize
+    @file = "./ready"
+  end
+
+  def ready?
+    enabled?
+  end
+end
+
+class Sleep
+  include Singleton
+  include State
+
+  def initialize
+    @file = "./sleep"
+  end
+
+  def asleep?
+    enabled?
+  end
+
+  def wake
+    disable
+  end
+
+  def sleep
+    enable
+  end
+end
+
+def master_pid
+  pid_s = File.read PID_FILE_PATH
+  Integer pid_s.strip
+end
+
+def system_uptime
+  uptime_s = File.read PROC_UPTIME_PATH
+  Float uptime_s.strip.split[0]
+end
+
+##
+# Convert to human friendly time interval
+#
+# @param [Integer] time in seconds
+def human_time(seconds, delim = " ")
+  s = []
+  DURATION_PARTS.each do |divisor, unit, abbrev|
+    q = seconds / divisor
+    r = seconds % divisor
+    s.push "#{q}#{abbrev}" if q.positive?
+    seconds = r
+  end
+
+  s.join delim
+end
+
+Health.instance.up
+Ready.instance.up
+Sleep.instance.wake
+
+enable :sessions
+
+configure do
+  mime_type :json, "application/json"
+end
+
+before do
+  # content_type 'text/plain'
+  sleep(1) while Sleep.instance.asleep? unless request.path_info == "/livez/sleep"
+end
+
+get "/" do
+  "hello there!\n"
+end
+
+get "/env" do
+  stream do |out|
+    ENV.sort.each do |k, v|
+      out << "#{k}=#{v}\n"
+    end
+  end
+end
+
+get "/headers", provides: "json" do
+  h = req_headers
+  return JSON.pretty_generate h if params.key? "pretty"
+
+  JSON.generate h
+end
+
+get "/headers" do
+  stream do |out|
+    req_headers.each do |k, v|
+      out << "#{k}: #{v.inspect}\n"
+    end
+  end
+end
+
+get "/livez" do
+  error 503 unless Health.instance.healthy?
+
+  return Health.instance.to_json if request.env["HTTP_ACCEPT"] == "application/json"
+
+  Health.instance.to_s
+end
+
+get "/livez/uptime" do
+  tt = TickTock.new
+  x = { started_at: tt.started_at, seconds: tt.uptime.to_i, human: human_time(tt.uptime.to_i) }
+  json x
+end
+
+post "/livez/toggle" do
+  Health.instance.toggle
+  "ok\n"
+end
+
+post "/livez/sleep" do
+  Sleep.instance.toggle
+  "ok\n"
+end
+
+get "/uuid" do
+  n = params.fetch(:n, 1).to_i
+  stream do |out|
+    n.times do |_|
+      out << format("%s\n", SecureRandom.uuid)
+    end
+  end
+end
+
+get "/ulid" do
+  n = params.fetch(:n, 1).to_i
+  stream do |out|
+    n.times do |_|
+      out << format("%s\n", ULID.generate)
+    end
+  end
+end
+
+get "/snowflake" do
+  n = params.fetch(:n, 1).to_i
+  epoch = Time.new(2016, 7, 1, 0, 0, 0).strftime("%s%L").to_i
+  node_id = 1
+  af = AnyFlake.new(epoch, node_id)
+  stream do |out|
+    n.times do |_|
+      out << format("%s\n", af.next_id)
+    end
+  end
+end
+
+post "/quit" do
+  Process.kill("TERM", master_pid)
+  nil
+end
+
+post "/halt" do
+  Process.kill("QUIT", master_pid)
+  nil
+end
+
+get "/pid" do
+  JSON.generate({ puma: master_pid, pid: Process.pid })
+end
+
+get "/token" do
+  exp = Time.now.to_i + SECONDS_PER_MINUTE * 2
+  payload = { name: "anonymous", exp: exp, jti: Random.uuid }
+  expires_at = Time.at(exp).to_datetime
+  token = JWT.encode payload, JWT_SECRET, "HS256"
+  token
+  x = { :token => token, :expires_at => expires_at }
+  json x
+end
+
+get "/token/validate" do
+  token = req_headers["authorization"].split[1]
+  payload = JWT.decode token, JWT_SECRET, true, algorithm: "HS256"
+  json payload
+end
+
+post "/session" do
+  session.merge! params
+  json session.to_hash
+end
+
+get "/session" do
+  json session.to_hash
+end
+
+get "/cookies" do
+  json response.headers
+end