herokuでgit push heroku masterが通らない(rails)

Question

herokuでgit push heroku masterを実行すると、以下のようなエラーが出てしまいます。
（こちらのサイトを参考にしました）
想像でいいので、間違っている可能性のある部分を教えていただけませんか？
試したことなども下に乗せています。

C:\Users\user>git push heroku master
Enumerating objects: 4234, done.
Counting objects: 100% (4234/4234), done.
Delta compression using up to 4 threads
Compressing objects: 100% (3792/3792), done.
Writing objects: 100% (4234/4234), 10.54 MiB | 1.91 MiB/s, done.
Total 4234 (delta 544), reused 0 (delta 0), pack-reused 0
remote: Compressing source files... done.
remote: Building source:
remote:
remote:  !     No default language could be detected for this app.
remote:                         HINT: This occurs when Heroku cannot detect the buildpack to use for this application automatically.
remote:                         See https://devcenter.heroku.com/articles/buildpacks
remote:
remote:  !     Push failed
remote: Verifying deploy...
remote:
remote: !       Push rejected to sheltered-crag-86184.
remote:
To https://git.heroku.com/sheltered-crag-86184.git
 ! [remote rejected] master -> master (pre-receive hook declined)
error: failed to push some refs to 'https://git.heroku.com/sheltered-crag-86184.git'

その前にやったこと

前述のサイトのとおり、

• ・gemfileでデータベースの変更
• ・config/datebase.ymlを変更
• ・config/environments/production.rbを変更
• ・bin以下のフォルダを変更

を行ったつもりです。
###変更したファイル一覧
bin/bundle

#!/usr/bin/env ruby
ENV['BUNDLE_GEMFILE'] ||= File.expand_path('../Gemfile', __dir__)
load Gem.bin_path('bundler', 'bundle')

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

ruby '2.5.1'

# Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
gem 'rails', '~> 5.2.4', '>= 5.2.4.1'
# Use sqlite3 as the database for Active Record
#gem 'sqlite3'
# Use Puma as the app server
gem 'puma', '~> 3.11'
# Use SCSS for stylesheets
gem 'sass-rails', '~> 5.0'
# Use Uglifier as compressor for JavaScript assets
gem 'uglifier', '>= 1.3.0'
# See https://github.com/rails/execjs#readme for more supported runtimes
gem 'duktape'
# Use CoffeeScript for .coffee assets and views
gem 'coffee-rails', '~> 4.2'
# 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', '~> 2.5'
# Use Redis adapter to run Action Cable in production
# gem 'redis', '~> 4.0'
# Use ActiveModel has_secure_password
# gem 'bcrypt', '~> 3.1.7'

# Use ActiveStorage variant
# gem 'mini_magick', '~> 4.8'

# Use Capistrano for deployment
# gem 'capistrano-rails', group: :development

# Reduces boot times through caching; required in config/boot.rb

gem 'bootsnap', '>= 1.1.0', require: false

gem 'bcrypt'

group :development, :test do
  gem 'sqlite3'
  # Call 'byebug' anywhere in the code to stop execution and get a debugger console
  gem 'byebug', platforms: [:mri, :mingw, :x64_mingw]
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'
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 chromedriver to run system tests with Chrome
  gem 'chromedriver-helper'
end

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

group :production do
  gem 'pg'
end

config/datebase.yml

# SQLite version 3.x
#   gem install sqlite3
#
#   Ensure the SQLite 3 gem is defined in your Gemfile
#   gem 'sqlite3'
#
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
  adapter: postgresql
  encoding: unicode
  pool: 5

config/environments/production.rb

Rails.application.configure do
  # Settings specified here will take precedence over those in config/application.rb.

  # Code is not reloaded between requests.
  config.cache_classes = true

  # Eager load code on boot. This eager loads most of Rails and
  # your application in memory, allowing both threaded web servers
  # and those relying on copy on write to perform better.
  # Rake tasks automatically ignore this option for performance.
  config.eager_load = true

  # Full error reports are disabled and caching is turned on.
  config.consider_all_requests_local       = false
  config.action_controller.perform_caching = true

  # Ensures that a master key has been made available in either ENV["RAILS_MASTER_KEY"]
  # or in config/master.key. This key is used to decrypt credentials (and other encrypted files).
  # config.require_master_key = true

  # Disable serving static files from the `/public` folder by default since
  # Apache or NGINX already handles this.
  config.public_file_server.enabled = ENV['RAILS_SERVE_STATIC_FILES'].present?

  # Compress JavaScripts and CSS.
  config.assets.js_compressor = :uglifier
  # config.assets.css_compressor = :sass

  # Do not fallback to assets pipeline if a precompiled asset is missed.
  config.assets.compile = true

  # `config.assets.precompile` and `config.assets.version` have moved to config/initializers/assets.rb

  # Enable serving of images, stylesheets, and JavaScripts from an asset server.
  # config.action_controller.asset_host = 'http://assets.example.com'

  # Specifies the header that your server uses for sending files.
  # config.action_dispatch.x_sendfile_header = 'X-Sendfile' # for Apache
  # config.action_dispatch.x_sendfile_header = 'X-Accel-Redirect' # for NGINX

  # Store uploaded files on the local file system (see config/storage.yml for options)
  config.active_storage.service = :local

  # Mount Action Cable outside main process or domain
  # config.action_cable.mount_path = nil
  # config.action_cable.url = 'wss://example.com/cable'
  # config.action_cable.allowed_request_origins = [ 'http://example.com', /http://example.*/ ]

  # Force all access to the app over SSL, use Strict-Transport-Security, and use secure cookies.
  # config.force_ssl = true

  # Use the lowest log level to ensure availability of diagnostic information
  # when problems arise.
  config.log_level = :debug

  # Prepend all log lines with the following tags.
  config.log_tags = [ :request_id ]

  # Use a different cache store in production.
  # config.cache_store = :mem_cache_store

  # Use a real queuing backend for Active Job (and separate queues per environment)
  # config.active_job.queue_adapter     = :resque
  # config.active_job.queue_name_prefix = "chat_spot_#{Rails.env}"

  config.action_mailer.perform_caching = false

  # Ignore bad email addresses and do not raise email delivery errors.
  # Set this to true and configure the email server for immediate delivery to raise delivery errors.
  # config.action_mailer.raise_delivery_errors = false

  # Enable locale fallbacks for I18n (makes lookups for any locale fall back to
  # the I18n.default_locale when a translation cannot be found).
  config.i18n.fallbacks = true

  # Send deprecation notices to registered listeners.
  config.active_support.deprecation = :notify

  # Use default logging formatter so that PID and timestamp are not suppressed.
  config.log_formatter = ::Logger::Formatter.new

  # Use a different logger for distributed setups.
  # require 'syslog/logger'
  # config.logger = ActiveSupport::TaggedLogging.new(Syslog::Logger.new 'app-name')

  if ENV["RAILS_LOG_TO_STDOUT"].present?
    logger           = ActiveSupport::Logger.new(STDOUT)
    logger.formatter = config.log_formatter
    config.logger    = ActiveSupport::TaggedLogging.new(logger)
  end

  # Do not dump schema after migrations.
  config.active_record.dump_schema_after_migration = false
end

Answer 1

git pushのログを見ると、

remote: ! No default language could be detected for this app.

となっているので、heroku側がrailsアプリだと自動的に認識できなかったのだと思われます。
Herokuの管理画面から、rubyのビルドパックを入れた上で再度試してみてはどうでしょうか？

Comments

[aspot_0734]

いろいろ調べて、デスクトップからherokuの設定画面のビルドパックを追加したのですが、また同じエラーが出てしまいます。ビルドパックの欄には「heroku/ruby」と表示されています。

[sss]

ビルドパックの設定はそれであっています。
添付のログを見ると、
C:\Users\user>git push heroku master

となっており、Windoｗsのユーザーのホームのディレクトリ(C:\Users\user)でgit push heroku masterをしているように見えます。
git push heroku masteは、Railsアプリのルートディレクトリで実行されていますか？

[aspot_0734]

cd で移動してからまたやってみましたが、なぜかできません。
可能性でいいので、またお願いします。

[sss]

Railsアプリのルートディレクトリで、git initされてますか？
まだしてないのなら、git initした後、git add .をしてコミットしてください。

[aspot_0734]

デプロイできました！
しかし、そのURLにアクセスすると
Method Not Allowed
となってしまいます。
別の質問として出してこの質問は閉じたほうが良いでしょうか？

[sss]

そうですね。ここで、出されている情報では、Method Not Allowedの原因を探りづらいので、別の質問として、経緯や関連のコードとともに出されたほうがよいと思います。