Herokuへポートフォリオのの情報を追加出来ません。git push heroku master後のエラー解決をお願いいたします！

Question

前提・実現したいこと

git push heroku masterを実行して、
Herokuへアプリケーションを追加すること。

##発生している問題・エラーメッセージ
オリジナルアプリを作成しています。
下記のコマンドを実行した所、エラーが発生します。
% git push heroku master

remote: !
remote: ! Failed to install gems via Bundler.
remote: !
remote: ! Push rejected, failed to compile Ruby app.
remote:
remote: ! Push failed
remote: Verifying deploy...
remote:
remote: ! Push rejected to xxxx-xxxx.
remote:
To https://git.heroku.com/xxxx-xxxx.git
! [remote rejected] master -> master (pre-receive hook declined)
error: failed to push some refs to 'https://git.heroku.com/xxxx-xxxx.git'

該当のソースコード

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

ruby '2.6.5'

# Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
gem 'rails', '~> 6.0.0'
# Use mysql as the database for Active Record
gem 'mysql2', '>= 0.4.4'
# Use Puma as the app server
gem 'puma', '~> 3.11'
# Use SCSS for stylesheets
gem 'sass-rails', '~> 5'
# 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]
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', '>= 3.0.5', '< 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

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

group :development do
  gem 'rubocop', require: false
end

gem 'active_hash'


gem 'devise'


gem 'pry-rails'

試したこと

二点。

・Gemfile.lockが下記の状態であることを確認。
RUBY VERSION
ruby 2.6.5p114

BUNDLED WITH
2.1.4

・下記コマンドを実行して、Herokuで利用するStackを指定。
heroku stack:set heroku-20 -a

補足情報（FW/ツールのバージョンなど）

予想としてはbundlerのバーションを2.2.5→2.1.4へ下げ流必要がある。

言い方をかえるとHeroku環境のbundlerのversionとローカル環境のbundlerのversionを一致させた。今回の場合は、Herokuのbundlerが2.1.4だったけど、ローカルでは2.2.5だったため、Herokuにpushした際にエラーが発生した。

ローカル環境のbundlerのversion変更方法が分かりません。

Comments

[mather]

エラーメッセージはそれで全てですか？ bundle install を実行している部分のログは出力されていませんか？

[sn007]

ご返信ありがとうございます。
その他のエラーメッセージはこちらです。ご確認お願い致します。

Enumerating objects: 248, done.
Counting objects: 100% (248/248), done.
Delta compression using up to 4 threads
Compressing objects: 100% (224/224), done.
Writing objects: 100% (248/248), 305.15 KiB | 3.51 MiB/s, done.
Total 248 (delta 71), reused 0 (delta 0), pack-reused 0
remote: Compressing source files... done.
remote: Building source:
remote:
remote: -----> Building on the Heroku-18 stack
remote: -----> Determining which buildpack to use for this app
remote: ! Warning: Multiple default buildpacks reported the ability to handle this app. The first buildpack in the list below will be used.
remote: Detected buildpacks: Ruby,Node.js
remote: See https://devcenter.heroku.com/articles/buildpacks#buildpack-detect-order
remote: -----> Ruby app detected
remote: -----> Installing bundler 2.2.16
remote: -----> Removing BUNDLED WITH version in the Gemfile.lock
remote: -----> Compiling Ruby/Rails
remote: -----> Using Ruby version: ruby-2.6.5
remote: -----> Installing dependencies using bundler 2.2.16
remote: Running: BUNDLE_WITHOUT='development:test' BUNDLE_PATH=vendor/bundle BUNDLE_BIN=vendor/bundle/bin BUNDLE_DEPLOYMENT=1 bundle install -j4
remote: Fetching gem metadata from https://rubygems.org/............
remote: Your bundle is locked to mimemagic (0.3.5) from rubygems repository
remote: https://rubygems.org/ or installed locally, but that version can no longer be
remote: found in that source. That means the author of mimemagic (0.3.5) has removed it.
remote: You'll need to update your bundle to a version other than mimemagic (0.3.5) that
remote: hasn't been removed in order to install.
remote: Bundler Output: Fetching gem metadata from https://rubygems.org/............
remote: Your bundle is locked to mimemagic (0.3.5) from rubygems repository
remote: https://rubygems.org/ or installed locally, but that version can no longer be
remote: found in that source. That means the author of mimemagic (0.3.5) has removed it.
remote: You'll need to update your bundle to a version other than mimemagic (0.3.5) that
remote: hasn't been removed in order to install.
remote:

Answer 1

お手元の環境では mimemagic (0.3.5) がインストールされているようですが、現在はすでに利用できないようです。

remote: Your bundle is locked to mimemagic (0.3.5) from rubygems repository
remote: https://rubygems.org/ or installed locally, but that version can no longer be
remote: found in that source. That means the author of mimemagic (0.3.5) has removed it.

詳しいことは mimemagic でググってみると良いのですが、以下のページがヒットします。
https://hackmd.io/@mametter/mimemagic-info-ja

簡単な対処法は Rails のバージョンを更新することです。