Refactored encoding of build output.

Moved the GitlabCi::Encode.encode! method call closer to the file read.
This keeps the boundary between "external file source with crazy
encoding -> internal rails code all in utf-8" well defined.
Additionally the build output file is opened in binary mode to prevent
encoding exceptions while reading it. It will be converted to utf-8 by
GitlabCi::Encode.encode!

app/models/build.rb

@@ -73,8 +73,7 @@ class Build < ActiveRecord::Base
   def write_trace(trace)
     self.reload
-    sanitized_output = sanitize_build_output(trace)
-    update_attributes(trace: sanitized_output)
+    update_attributes(trace: trace)
   end
   def short_before_sha
@@ -86,22 +85,12 @@ class Build < ActiveRecord::Base
   end
   def trace_html
-    if trace.present?
-      Ansi2html::convert(compose_output)
-    else
-      ''
-    end
-  end
-
-  def sanitize_build_output(output)
-    GitlabCi::Encode.encode!(output)
+    html = Ansi2html::convert(compose_output) if trace.present?
+    html ||= ''
   end
   def read_tmp_file
-    content = if tmp_file && File.readable?(tmp_file)
-                File.read(tmp_file)
-              end
-
+    content = GitlabCi::Encode.encode!(File.binread(tmp_file)) if tmp_file && File.readable?(tmp_file)
     content ||= ''
   end
@@ -109,8 +98,7 @@ class Build < ActiveRecord::Base
     output = trace
     if running?
-      sanitized_output = sanitize_build_output(read_tmp_file)
-      output << sanitized_output if sanitized_output.present?
+      output << read_tmp_file
     end
     output

lib/runner.rb

@@ -75,7 +75,7 @@ class Runner
     @output << "\n"
     @process = ChildProcess.build(cmd)
-    @tmp_file = Tempfile.new("child-output")
+    @tmp_file = Tempfile.new("child-output", binmode: true)
     @process.io.stdout = @tmp_file
     @process.io.stderr = @tmp_file
     @process.cwd = path
@@ -98,7 +98,9 @@ class Runner
     @process.exit_code == 0
   ensure
     @tmp_file.rewind
-    @output << @tmp_file.read
+    @output << GitlabCi::Encode.encode!(@tmp_file.read)
+    @tmp_file.close
+    @tmp_file.unlink
   end
   def prepare_project_cmd(path, ref)