Coach: Explain what specifying the image width in HTML at the end of Part 4 does and how it differs from resizing images on the server.
1. Installing ImageMagick
OS X: run brew install imagemagick. If you don’t have the brew command, you can install Homebrew here. After installation, close and reopen the terminal to make sure imagemagick is loaded correctly
Windows: download and run the ImageMagick installer (use the first download link). In the installation wizard, make sure you check the checkbox to install legacy binaries. After installation, close and reopen GitBash, and Command Prompt with Ruby and Rails.
Linux: On Ubuntu and Debian, run sudo apt-get install imagemagick. Use the appropriate package manager instead of apt-get for other distributions. After installation, close and reopen the terminal to make sure imagemagick is loaded correctly
Coach: What is ImageMagick and how is it different from libraries/gems we used before?
Open Gemfile in the project and add
gem 'mini_magick','4.9.5'
under the line
gem 'carrierwave'
In the Terminal run:
bundle
2. Telling our app to create thumbnails when an image is uploaded
Open app/uploaders/picture_uploader.rb and find the line that looks like this:
# include CarrierWave::MiniMagick
Remove the # sign.
Coach: Explain the concept of comments in code.
Below the line you just changed, add:
The images uploaded from now on should be resized, but the ones we already have weren’t affected. So edit one of the existing ideas and re-add a picture.
3. Displaying the thumbnails
To see if the uploaded picture was resized open app/views/ideas/index.html.erb. Change the line
to
Take a look at the list of ideas in the browser to see if the thumbnail is there. You will probably need to re-upload the images for the new thumbnails to generate.
Our images are now resized/cropped to be 50x50px thumbnails
