Cloud9、Herokuにデプロイできない

rails tutorialをやっていたのですがHerokuにデプロイできていないことに気が付きました。3時間ほどGoogleで検索を書けていますが一向に解決しません。具体的に言うとターミナルで
git push heroku masterと打つと

Terminal
1Counting objects: 127, done.
2Compressing objects: 100% (110/110), done.
3Writing objects: 100% (127/127), 153.70 KiB | 3.75 MiB/s, done.
4Total 127 (delta 5), reused 0 (delta 0)
5remote: Compressing source files... done.
6remote: Building source:
7remote: 
8remote: -----> Building on the Heroku-20 stack
9remote:  !     Warning: Multiple default buildpacks reported the ability to handle this app. The first buildpack in the list below will be used.
10remote:                         Detected buildpacks: Ruby,Node.js
11remote:                         See https://devcenter.heroku.com/articles/buildpacks#buildpack-detect-order
12remote: -----> Ruby app detected
13remote: -----> Installing bundler 1.17.3
14remote: -----> Removing BUNDLED WITH version in the Gemfile.lock
15remote: -----> Compiling Ruby/Rails
16remote:        Command: 'set -o pipefail; curl -L --fail --retry 5 --retry-delay 1 --connect-timeout 3 --max-time 30 https://s3-external-1.amazonaws.com/heroku-buildpack-ruby/heroku-20/ruby-2.6.3.tgz -s -o - | tar zxf - ' failed on attempt 1 of 3.
17remote:        Command: 'set -o pipefail; curl -L --fail --retry 5 --retry-delay 1 --connect-timeout 3 --max-time 30 https://s3-external-1.amazonaws.com/heroku-buildpack-ruby/heroku-20/ruby-2.6.3.tgz -s -o - | tar zxf - ' failed on attempt 2 of 3.
18remote: 
19remote:  !
20remote:  !     The Ruby version you are trying to install does not exist on this stack.
21remote:  !     
22remote:  !     You are trying to install ruby-2.6.3 on heroku-20.
23remote:  !     
24remote:  !     Ruby ruby-2.6.3 is present on the following stacks:
25remote:  !     
26remote:  !     - cedar-14
27remote:  !     - heroku-16
28remote:  !     - heroku-18
29remote:  !     
30remote:  !     Heroku recommends you use the latest supported Ruby version listed here:
31remote:  !     https://devcenter.heroku.com/articles/ruby-support#supported-runtimes
32remote:  !     
33remote:  !     For more information on syntax for declaring a Ruby version see:
34remote:  !     https://devcenter.heroku.com/articles/ruby-versions
35remote:  !
36remote:  !     Push rejected, failed to compile Ruby app.
37remote: 
38remote:  !     Push failed
39remote:  !
40remote:  ! ## Warning - The same version of this code has already been built: 2dc56620d26562f11b369e73f71139f88b51ad39
41remote:  !
42remote:  ! We have detected that you have triggered a build from source code with version 2dc56620d26562f11b369e73f71139f88b51ad39
43remote:  ! at least twice. One common cause of this behavior is attempting to deploy code from a different branch.
44remote:  !
45remote:  ! If you are developing on a branch and deploying via git you must run:
46remote:  !
47remote:  !     git push heroku <branchname>:main
48remote:  !
49remote:  ! This article goes into details on the behavior:
50remote:  !   https://devcenter.heroku.com/articles/duplicate-build-version
51remote: 
52remote: Verifying deploy...
53remote: 
54remote: !       Push rejected to damp-inlet-19623.
55remote: 
56To https://git.heroku.com/damp-inlet-19623.git
57 ! [remote rejected] master -> master (pre-receive hook declined)
58error: failed to push some refs to 'https://git.heroku.com/damp-inlet-19623.git'

と表示されます。
Gemfileは

source 'https://rubygems.org'
git_source(:github) { |repo| "https://github.com/#{repo}.git" }

ruby '2.6.3'

# Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
gem 'rails', '~> 6.0.3'
# Use sqlite3 as the database for Active Record
# gem 'sqlite3', '~> 1.4'
# Use Puma as the app server
gem 'puma', '~> 4.1'
# Use SCSS for stylesheets
gem 'sass-rails', '>= 6'
# Transpile app-like JavaScript. Read more: https://github.com/rails/webpacker
gem 'webpacker', '~> 4.0'
# Turbolinks makes navigating your web application faster. Read more: https://github.com/turbolinks/turbolinks
gem 'turbolinks', '~> 5'
# Build JSON APIs with ease. Read more: https://github.com/rails/jbuilder
gem 'jbuilder', '~> 2.7'
# Use Redis adapter to run Action Cable in production
# gem 'redis', '~> 4.0'
# Use Active Model has_secure_password
# gem 'bcrypt', '~> 3.1.7'

# Use Active Storage variant
# gem 'image_processing', '~> 1.2'

# Reduces boot times through caching; required in config/boot.rb
gem 'bootsnap', '>= 1.4.2', require: false

group :development, :test do
  # Call 'byebug' anywhere in the code to stop execution and get a debugger console
  gem 'byebug', platforms: [:mri, :mingw, :x64_mingw]
  gem 'sqlite3'
  
  
end

group :development do
  # Access an interactive console on exception pages or by calling 'console' anywhere in the code.
  gem 'web-console', '>= 3.3.0'
  gem 'listen', '~> 3.2'
  # Spring speeds up development by keeping your application running in the background. Read more: https://github.com/rails/spring
  gem 'spring'
  gem 'spring-watcher-listen', '~> 2.0.0'
end

group :test do
  # Adds support for Capybara system testing and selenium driver
  gem 'capybara', '>= 2.15'
  gem 'selenium-webdriver'
  # Easy installation and use of web drivers to run system tests with browsers
  gem 'webdrivers'
  
end

group :production do
  gem 'pg'
end


# Windows does not include zoneinfo files, so bundle the tzinfo-data gem
gem 'tzinfo-data', platforms: [:mingw, :mswin, :x64_mingw, :jruby]
gem 'slim-rails'
gem 'html2slim'
gem 'bcrypt'

で、database.ymlは

default: &default
  adapter: sqlite3
  pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
  timeout: 5000

development:
  <<: *default
  database: db/development.sqlite3

# Warning: The database defined as "test" will be erased and
# re-generated from your development database when you run "rake".
# Do not set this db to the same as development or production.
test:
  <<: *default
  database: db/test.sqlite3

production:
  # <<: *default
  # database: db/production.sqlite3
  adapter: postgresql
  encoding: unicode
  pool: 5
  database: db/production.postgresql

です。
git init
git add -A
git commit
git remote add origin https://github.com/<私のGitHubアカウント名>/hello_app.git
git push origin master
herokuのversion確認、
heroku login --interactive
heroku create
まで完了しております。

どなたか解決方法をご教授いただけると幸いです。

行動規範の内容に同意します

回答2件

ベストアンサー

エラーメッセージの下記の部分がそのまんま答えです。
使用しているRubyのバージョンがheroku-20の環境では対応していないそうなのでURLを参考に対応しているバージョンを使うか、対応しているherokuの環境を使うしかないと思います。

remote: ! The Ruby version you are trying to install does not exist on this stack.

remote: !
remote: ! You are trying to install ruby-2.6.3 on heroku-20.
remote: !
remote: ! Ruby ruby-2.6.3 is present on the following stacks:
remote: !
remote: ! - cedar-14
remote: ! - heroku-16
remote: ! - heroku-18
remote: !
remote: ! Heroku recommends you use the latest supported Ruby version listed here:
remote: ! https://devcenter.heroku.com/articles/ruby-support#supported-runtimes
remote: !
remote: ! For more information on syntax for declaring a Ruby version s

投稿2021/01/30 16:07

yu_1985

総合スコア7595

nekoyama141592

2021/01/31 04:34

（既にheroku createしていたのでアプリを削除し、一から作り直した） 'heroku login --interactive` のあとに 'heroku stack:set heroku-18` でheroku-20からruby2.6.3に対応しているheroku-18に下げて `git push heroku master` でうまくいきました！！ yu_1985さん！本当にありがとうございました！！！

行動規範の内容に同意します

Railsチュートリアルの本文では、Gemfileからruby '2.6.3'の行を削除するように指示されています。
ですので、stackを下げるのではなく、この指示に従うのがRailsチュートリアルの進め方として最適です。

最後に、Rubyの正確なバージョン番号を指定する行（ruby '2.6.3'）をリスト 1.5から削除している点に注意してください。業務でWebサービスを開発する場面では削除しないことをオススメしますが、本チュートリアルでは、この行が残っているとエラーになる可能性が高まります。

https://railstutorial.jp/chapters/beginning?version=6.0#sec-bundler

詳しい内容は以下にまとめたので、こちらをご覧ください。

【初心者向け】RailsチュートリアルでHerokuデプロイ時に「Ruby 2.6.3はインストールできない」と言われたときの適切な対処方法 - Qiita

投稿2021/02/19 22:50