Merge pull request #32 from Vidyard/CRT-2193-S3-TMP-PROCESSING

[CRT-2193] Create tmp dir for interim file to process

Author: MilesPurvis

lib/ffmpeg/transcoder.rb

@@ -5,6 +5,7 @@
 
 FIXED_LOWER_TO_UPPER_RATIO = 16.0/9.0
 FIXED_UPPER_TO_LOWER_RATIO = 9.0/16.0
+TEMP_DIR = "/tmp/rlovelett".freeze
 
 module FFMPEG
   class Transcoder
@@ -36,16 +37,18 @@ def initialize(movie, output_file, options = EncodingOptions.new, transcoder_opt
       if requires_pre_encode
         @movie.paths.each do |path|
           # Make the interim path folder if it doesn't exist
-          dirname = "#{File.dirname(path)}/interim"
+
+          dirname = "#{TEMP_DIR}/interim#{File.dirname(path)}/"
           unless File.directory?(dirname)
             FileUtils.mkdir_p(dirname)
           end
-
-          interim_path = "#{File.dirname(path)}/interim/#{File.basename(path, File.extname(path))}_#{SecureRandom.urlsafe_base64}.mp4"
+          # Example output: /tmp/rlovelett/interim/test_gv6Hw86ryqklKNiYCu9a8w.mp4
+          interim_path = "#{dirname}#{File.basename(path, File.extname(path))}_#{SecureRandom.urlsafe_base64}.mp4"
           @movie.interim_paths << interim_path
         end
       else
         @movie.interim_paths << @movie.paths
+        @movie.interim_paths.flatten!
       end
 
       if options.is_a?(String)
@@ -171,7 +174,14 @@ def delete_files(destination)
     def transcode_movie
       pre_encode_if_necessary
 
-      @command = "#{@movie.ffmpeg_command} -y #{@raw_options} #{Shellwords.escape(@output_file)}"
+      temp_output_dir = "#{TEMP_DIR}/output/"
+      FileUtils.mkdir_p(temp_output_dir) unless File.directory?(temp_output_dir)
+
+      # We use a temporary output file to avoid issues with manipulating the output file directly in ffmpeg, which can occur due to s3 mountpoint restrictions.
+      # Example output: /tmp/rlovelett/output/test_gv6Hw86ryqklKNiYCu9a8w.mp4
+      temp_output_file = "#{temp_output_dir}#{File.basename(@output_file, File.extname(@output_file))}_#{SecureRandom.urlsafe_base64}#{File.extname(@output_file)}"
+
+      @command = "#{@movie.ffmpeg_command} -y #{@raw_options} #{Shellwords.escape(temp_output_file)}"
 
       FFMPEG.logger.info("Running transcoding...\n#{@command}\n")
       @output = ""
@@ -204,6 +214,16 @@ def transcode_movie
           raise Error, "Process hung. Full output: #{@output}"
         end
       end
+
+      # Copy temp_output_file to output_file and cleanup interim paths
+      if File.exist?(temp_output_file)
+        FileUtils.cp(temp_output_file, @output_file)
+        FileUtils.rm_rf(temp_output_file)
+      end
+    ensure
+      @movie.interim_paths.each do |path|
+        FileUtils.rm_rf(path) if path.start_with?(TEMP_DIR)
+      end
     end
 
     def validate_output_file(&block)

spec/ffmpeg/transcoder_spec.rb

@@ -1,4 +1,5 @@
 require 'spec_helper.rb'
+require 'fileutils'
 
 module FFMPEG
   describe Transcoder do
@@ -427,5 +428,28 @@ module FFMPEG
         expect(transcoder.requires_pre_encode).to be false
       end
     end
+
+    describe "#handle_temp_files" do
+      let(:temp_output_file) { %r{#{TEMP_DIR}/output/output_.*\.mp4} }
+      let(:output_file) { "#{tmp_path}/output.mp4" }
+      let(:interim_path) { "#{TEMP_DIR}/interim/interim_path.mp4" }
+      let(:transcoder) { Transcoder.new(movie, output_file, EncodingOptions.new) }
+
+      it 'copies the temp output file to the final output file' do
+        expect(FileUtils).to receive(:cp).with(temp_output_file, output_file)
+        transcoder.send(:transcode_movie)
+      end
+
+      it 'removes the temp output file' do
+        expect(FileUtils).to receive(:rm_rf).with(temp_output_file)
+        transcoder.send(:transcode_movie)
+      end
+
+      it 'removes interim paths' do
+        movie.interim_paths << interim_path
+        expect(FileUtils).to receive(:rm_rf).with(interim_path)
+        transcoder.send(:transcode_movie)
+      end
+    end
   end
 end