###heroku apps:infoを実行
ターミナル
% heroku apps:info
===***-app-*****.
Addons: cleardb:ignite
Auto Cert Mgmt: false
Dynos: web: 1
Git URL: https://git.heroku.com/***-app-*****.git
Owner: sample@sample.com
Region: us
Repo Size: 165 KB
Slug Size: 56 MB
Stack: heroku-**
Web URL: https:/*****-app-*****.herokuapp.com/
heroku logs --tail --app <<アプリケーション名>>
###【例】heroku logs --tail --app a***-app-****
ターミナル
2021-04-30T08:35:22.839682+00:00 heroku[web.1]: Starting process with command `bin/rails server -p ${PORT:-5000} -e production`
2021-04-30T08:35:30.766757+00:00 app[web.1]: => Booting Puma
2021-04-30T08:35:30.766813+00:00 app[web.1]: => Rails 6.0.3.6 application starting in production
cafe***@olive******.sakura.ne.jp
2021-04-30T08:47:21.738584+00:00 app[api]: Release v14 created by user cafe***@olive******.sakura.ne.jp
2021-04-30T08:47:21.738584+00:00 app[api]: Deploy c065f55e by user cafe***@olive******.sakura.ne.jp
2021-04-30T08:47:21.960860+00:00 heroku[web.1]: Restarting
2021-04-30T08:47:21.974003+00:00 heroku[web.1]: State changed from up to starting
2021-04-30T08:47:23.387217+00:00 heroku[web.1]: Stopping all processes with SIGTERM
2021-04-30T08:47:23.489523+00:00 app[web.1]: - Gracefully stopping, waiting for requests to finish
2021-04-30T08:47:23.547863+00:00 app[web.1]: === puma shutdown: 2021-04-30 08:47:23 +0000 ===
2021-04-30T08:47:23.547896+00:00 app[web.1]: - Goodbye!
2021-04-30T08:47:42.762010+00:00 app[web.1]: * Environment: production
2021-04-30T09:18:24.501762+00:00 app[web.1]: === puma shutdown: 2021-04-30 09:18:24 +0000 ===
cafe***@olive******.sakura.ne.jp
2021-04-30T09:53:36.022502+00:00 heroku[web.1]: State changed from down to starting
2021-04-30T09:53:39.000000+00:00 app[api]: Build succeeded
2021-04-30T09:53:45.391721+00:00 heroku[web.1]: Starting process with command `bin/rails server -p ${PO**:-*0**} -e production`
2021-04-30T09:53:54.356026+00:00 app[web.1]: => Booting Puma
2021-04-30T09:53:54.356085+00:00 app[web.1]: => Rails 6.0.3.6 application starting in production
2021-04-30T09:53:54.356085+00:00 app[web.1]: => Run `rails server --help` for more startup options
2021-04-30T09:59:29.855528+00:00 app[api]: Release v** created by user cafe***@olive******.sakura.ne.jp
2021-04-30T09:59:30.176191+00:00 heroku[web.1]: Restarting
2021-04-30T09:59:30.197190+00:00 heroku[web.1]: State changed from up to starting
2021-04-30T09:59:31.254922+00:00 heroku[web.1]: Stopping all processes with SIGTERM
2021-04-30T09:59:31.330731+00:00 app[web.1]: - Gracefully stopping, waiting for requests to finish
2021-04-30T09:59:31.341751+00:00 app[web.1]: === puma shutdown: 2021-04-30 09:59:31 +0000 ===
2021-04-30T09:59:31.341754+00:00 app[web.1]: - Goodbye!
2021-04-30T09:59:42.042358+00:00 app[web.1]: => Run `rails server --help` for more startup options
2021-04-30T09:59:43.113738+00:00 app[web.1]: Puma starting in single mode...
2021-04-30T09:59:43.113772+00:00 app[web.1]: * Version 3.12.6 (ruby 2.6.5-p114), codename: L*****s in P*******s
2021-04-30T09:59:46.449298+00:00 app[api]: Release v17 created by user cafe***@olive******.sakura.ne.jp
2021-04-30T09:59:46.724617+00:00 heroku[web.1]: Restarting
2021-04-30T09:59:46.736251+00:00 heroku[web.1]: State changed from up to starting
2021-04-30T09:59:47.648532+00:00 heroku[web.1]: Stopping all processes with SIGTERM
2021-04-30T09:59:47.715254+00:00 app[web.1]: - Gracefully stopping, waiting for requests to finish
2021-04-30T09:59:47.716038+00:00 app[web.1]: === puma shutdown: 2021-04-30 09:59:47 +0000 ===
2021-04-30T09:59:58.571860+00:00 app[web.1]: => Rails 6.0.3.6 application starting in production
2021-04-30T09:59:58.571860+00:00 app[web.1]: => Run `rails server --help` for more startup options
2021-04-30T09:59:59.839376+00:00 app[web.1]: Puma starting in single mode...
2021-04-30T09:59:59.839392+00:00 app[web.1]: * Version 3.12.6 (ruby 2.6.5-p114), codename: L****s in P******s
2021-04-30T09:59:59.839393+00:00 app[web.1]: * Min threads: 5, max threads: 5
2021-04-30T09:59:59.839393+00:00 app[web.1]: * Environment: production
2021-04-30T09:59:59.839622+00:00 app[web.1]: * Listening on tcp://0.0.0.0:18031
2021-04-30T09:59:59.839910+00:00 app[web.1]: Use Ctrl-C to stop
2021-04-30T10:00:00.402077+00:00 heroku[web.1]: State changed from starting to up
##最新のlogは下にでます.