[Rails] How to upload images to AWS S3 using Carrierwave and fog-aws

Target

Development environment

・ Ruby: 2.5.7 Rails: 5.2.4 ・ Vagrant: 2.2.7 -VirtualBox: 6.1 ・ OS: macOS Catalina

Premise

You have already registered an AWS account.

The following has been implemented.

・ Implementation of posting function -Implementation of image posting function using Carrierwave

AWS settings

1. Access the link below

AWS Management Console (https://ap-northeast-1.console.aws.amazon.com/console/home?region=ap-northeast-1)

2. Click Service

3. Click ʻIAM`

4. Click User

5. Click Add User

6. User details settings

** ① Enter your user name. (Appropriate) **

** ② Set the access type to programmatic access. ** **

** ③ Click Next Step: Access Restriction **

7. Click Attach existing policy directly

8.Select ʻAmazonS3FullAccess and click Next Step: Tag`

9. Click Next Step: Confirm

10. Click Create User

11. Copy the access key ID and secret access key, make a note of them, and click service.

12. Click S3

13. Click Create Bucket

14. Set name and region

** ① Enter the bucket name. (Appropriate) **

** ② Set the region to Asia Pacific (Tokyo). ** **

** ③ Click Next. ** **

14. Click Next

15. Click Next

16. Click Create Bucket

Implementation

1. Make the key an environment variable

** ① Introduced "gem'dotenv-rails'" **

Gemfile

gem 'dotenv-rails'

Terminal

& bundle

** ② Create a ".env" file directly under the application **

• Move to the application directory and then execute the following command

Terminal

$ touch .env 

** ③ Edit the .env file **

.env

S3_ACCESS_KEY_ID = 'access key' #Postscript
S3_SECRET_ACCESS_KEY = 'Secret access key' #Postscript

** ④ Edit the .gitignore file **

.gitignore

/.env #Postscript

2. Introduce Gem

Gemfile

gem 'fog-aws'

Terminal

$ bundle

3. Edit ʻimage_uploader.rb`

Comment out storage: file on the 7th line and add the following code.

image_uploader.rb

#Postscript
if Rails.env.development? #For development environment
  storage :file
elsif Rails.env.test? #For test environment
  storage :file
else #For production environment
  storage :fog
end

storage :file ➡︎ Upload the image into the application.

storage :fog ➡︎ Upload the image to S3.

4. Create / edit carrierwave.rb

Terminal

$ touch config/initializers/carrierwave.rb

carrierwave.rb

require 'carrierwave/storage/abstract'
require 'carrierwave/storage/file'
require 'carrierwave/storage/fog'

CarrierWave.configure do |config|
  if Rails.env.production? #Upload to S3 in production environment
    config.storage :fog
    config.fog_provider = 'fog/aws'
    config.fog_directory  = 'matsubishi-sample' #Bucket name
    config.fog_public = false
    config.fog_credentials = {
      provider: 'AWS',
      aws_access_key_id: ENV['S3_ACCESS_KEY_ID'], #access key
      aws_secret_access_key: ENV['S3_SECRET_ACCESS_KEY'], #Secret access key
      region: 'ap-northeast-1', #region
      path_style: true
    }
  else #Upload within the application if not in production
    config.storage :file
    config.enable_processing = false if Rails.env.test?
  end
end