FlyCTL is eager to say "The app is not listening on the expected address" when the app takes longer to bind

[lubien]

Describe the bug

Myself and a customer have been seeing flyctl report "The app is not listening on the expected address and will not be reachable by fly proxy..." very fast because our apps have slow boot times, mine being a NodeJS+puppeteer and theirs a rails app.

Deployment works as expected this might be a non-urgent display issue.

• Operating system; Mac M1 2022
• fly version: fly v0.2.15 darwin/arm64 Commit: 8466302-dirty BuildDate: 2024-03-10T09:52:28Z

** Paste your fly.toml

# fly.toml app configuration file generated for myapp on 2024-03-09T09:06:35+09:00
#
# See https://fly.io/docs/reference/configuration/ for information about how to use this file.
#

app = 'myapp'
primary_region = 'nrt'
console_command = '/rails/bin/rails console'
swap_size_mb = 512

[build]

[deploy]
  release_command = './bin/rails db:prepare'

[http_service]
  internal_port = 3000
  force_https = true
  auto_stop_machines = true
  auto_start_machines = true
  min_machines_running = 0
  processes = ['app']

[[vm]]
  memory = 256
  cpu_kind = 'shared'
  cpus = 1

** Command output: **

2024-03-11T02:41:27.581 app[784e667b274628] nrt [info] => Booting Puma

2024-03-11T02:41:27.581 app[784e667b274628] nrt [info] => Rails 7.0.4.3 application starting in production

2024-03-11T02:41:27.581 app[784e667b274628] nrt [info] => Run `bin/rails server --help` for more startup options

2024-03-11T02:41:30.007 app[784e667b274628] nrt [info] Puma starting in single mode...

2024-03-11T02:41:30.007 app[784e667b274628] nrt [info] * Puma version: 5.6.5 (ruby 3.2.2-p53) ("Birdie's Version")

2024-03-11T02:41:30.007 app[784e667b274628] nrt [info] * Min threads: 5

2024-03-11T02:41:30.007 app[784e667b274628] nrt [info] * Max threads: 5

2024-03-11T02:41:30.007 app[784e667b274628] nrt [info] * Environment: production

2024-03-11T02:41:30.008 app[784e667b274628] nrt [info] * PID: 305

2024-03-11T02:41:30.009 app[784e667b274628] nrt [info] * Listening on http://0.0.0.0:3000

2024-03-11T02:41:30.028 app[784e667b274628] nrt [info] Use Ctrl-C to stop