discourse/app/models/optimized_image.rb

249 lines
7.3 KiB
Ruby

require "digest/sha1"
require_dependency "file_helper"
require_dependency "url_helper"
require_dependency "db_helper"
require_dependency "file_store/local_store"
class OptimizedImage < ActiveRecord::Base
belongs_to :upload
# BUMP UP if optimized image algorithm changes
VERSION = 1
def self.create_for(upload, width, height, opts={})
return unless width > 0 && height > 0
return if upload.try(:sha1).blank?
DistributedMutex.synchronize("optimized_image_#{upload.id}_#{width}_#{height}") do
# do we already have that thumbnail?
thumbnail = find_by(upload_id: upload.id, width: width, height: height)
# make sure we have an url
if thumbnail && thumbnail.url.blank?
thumbnail.destroy
thumbnail = nil
end
# return the previous thumbnail if any
return thumbnail unless thumbnail.nil?
# create the thumbnail otherwise
original_path = Discourse.store.path_for(upload)
if original_path.blank?
external_copy = Discourse.store.download(upload) rescue nil
original_path = external_copy.try(:path)
end
if original_path.blank?
Rails.logger.error("Could not find file in the store located at url: #{upload.url}")
else
# create a temp file with the same extension as the original
extension = File.extname(original_path)
temp_file = Tempfile.new(["discourse-thumbnail", extension])
temp_path = temp_file.path
if extension =~ /\.svg$/i
FileUtils.cp(original_path, temp_path)
resized = true
else
resized = resize(original_path, temp_path, width, height, opts)
end
if resized
thumbnail = OptimizedImage.create!(
upload_id: upload.id,
sha1: Digest::SHA1.file(temp_path).hexdigest,
extension: extension,
width: width,
height: height,
url: "",
)
# store the optimized image and update its url
File.open(temp_path) do |file|
url = Discourse.store.store_optimized_image(file, thumbnail)
if url.present?
thumbnail.url = url
thumbnail.save
else
Rails.logger.error("Failed to store optimized image #{width}x#{height} for #{upload.url}")
end
end
else
Rails.logger.error("Failed to create optimized image #{width}x#{height} for #{upload.url}")
end
# close && remove temp file
temp_file.close!
end
# make sure we remove the cached copy from external stores
if Discourse.store.external?
external_copy.try(:close!) rescue nil
end
thumbnail
end
end
def destroy
OptimizedImage.transaction do
Discourse.store.remove_optimized_image(self)
super
end
end
def local?
!(url =~ /^(https?:)?\/\//)
end
def self.resize_instructions(from, to, dimensions, opts={})
# NOTE: ORDER is important!
%W{
convert
#{from}[0]
-gravity center
-background transparent
-thumbnail #{dimensions}^
-extent #{dimensions}
-interpolate bicubic
-unsharp 2x0.5+0.7+0
-quality 98
#{to}
}
end
def self.resize_instructions_animated(from, to, dimensions, opts={})
%W{
gifsicle
#{from}
--colors=256
--resize-fit #{dimensions}
--optimize=3
--output #{to}
}
end
def self.downsize_instructions(from, to, dimensions, opts={})
%W{
convert
#{from}[0]
-gravity center
-background transparent
-resize #{dimensions}#{!!opts[:force_aspect_ratio] ? "\\!" : "\\>"}
#{to}
}
end
def self.downsize_instructions_animated(from, to, dimensions, opts={})
resize_instructions_animated(from, to, dimensions, opts)
end
def self.resize(from, to, width, height, opts={})
optimize("resize", from, to, width, height, opts)
end
def self.downsize(from, to, max_width, max_height, opts={})
optimize("downsize", from, to, max_width, max_height, opts)
end
def self.optimize(operation, from, to, width, height, opts={})
dim = dimensions(width, height)
method_name = "#{operation}_instructions"
method_name += "_animated" if !!opts[:allow_animation] && from =~ /\.GIF$/i
instructions = self.send(method_name.to_sym, from, to, dim, opts)
convert_with(instructions, to)
end
def self.dimensions(width, height)
"#{width}x#{height}"
end
def self.convert_with(instructions, to)
`#{instructions.join(" ")} &> /dev/null`
return false if $?.exitstatus != 0
ImageOptim.new.optimize_image!(to)
true
rescue
Rails.logger.error("Could not optimize image: #{to}")
false
end
def self.migrate_to_new_scheme(limit=50)
problems = []
if SiteSetting.migrate_to_new_scheme
max_file_size_kb = SiteSetting.max_image_size_kb.kilobytes
local_store = FileStore::LocalStore.new
OptimizedImage.includes(:upload)
.where("url NOT LIKE '%/optimized/_X/%'")
.limit(limit)
.order(id: :desc)
.each do |optimized_image|
begin
# keep track of the url
previous_url = optimized_image.url.dup
# where is the file currently stored?
external = previous_url =~ /^\/\//
# download if external
if external
url = SiteSetting.scheme + ":" + previous_url
file = FileHelper.download(url, max_file_size_kb, "discourse", true) rescue nil
path = file.path
else
path = local_store.path_for(optimized_image)
file = File.open(path)
end
# compute SHA if missing
if optimized_image.sha1.blank?
optimized_image.sha1 = Digest::SHA1.file(path).hexdigest
end
# optimize if image
ImageOptim.new.optimize_image!(path)
# store to new location & update the filesize
File.open(path) do |f|
optimized_image.url = Discourse.store.store_optimized_image(f, optimized_image)
optimized_image.save
end
# remap the URLs
DbHelper.remap(UrlHelper.absolute(previous_url), optimized_image.url) unless external
DbHelper.remap(previous_url, optimized_image.url)
# remove the old file (when local)
unless external
FileUtils.rm(path, force: true) rescue nil
end
rescue => e
problems << { optimized_image: optimized_image, ex: e }
# just ditch the optimized image if there was any errors
optimized_image.destroy
ensure
file.try(:unlink) rescue nil
file.try(:close) rescue nil
end
end
end
problems
end
end
# == Schema Information
#
# Table name: optimized_images
#
# id :integer not null, primary key
# sha1 :string(40) not null
# extension :string(10) not null
# width :integer not null
# height :integer not null
# upload_id :integer not null
# url :string(255) not null
#
# Indexes
#
# index_optimized_images_on_upload_id (upload_id)
# index_optimized_images_on_upload_id_and_width_and_height (upload_id,width,height) UNIQUE
#