Allow optional extraction of archive in net_fetcher

Author: Przemysław Niekraś

README.md

@@ -151,7 +151,8 @@ Here is an example:
 name "ruby"
 default_version "1.9.2-p290"
 source url: "http://ftp.ruby-lang.org/pub/ruby/1.9/ruby-#{version}.tar.gz",
-       md5: "604da71839a6ae02b5b5b5e1b792d5eb"
+       md5: "604da71839a6ae02b5b5b5e1b792d5eb",
+       extract: false
 
 dependency "zlib"
 dependency "ncurses"

lib/omnibus/fetchers/net_fetcher.rb

@@ -44,6 +44,16 @@ def fetch_required?
       !(File.exist?(downloaded_file) && digest(downloaded_file, digest_type) == checksum)
     end
 
+    #
+    # A extract is required if the downloaded_file is an archive and
+    # source[:extract] is set to true if provided. Default: true
+    #
+    # @return [true, false]
+    #
+    def extract_required?
+      return false unless downloaded_file.end_with?(*ALL_EXTENSIONS)
+      !source.key?(:extract) ? true : source[:extract]
+    end
     #
     # The version identifier for this remote location. This is computed using
     # the name of the software, the version of the software, and the checksum.
@@ -182,11 +192,15 @@ def download
     # is copied over as a raw file.
     #
     def deploy
-      if downloaded_file.end_with?(*ALL_EXTENSIONS)
+      if downloaded_file.end_with?(*ALL_EXTENSIONS) && extract_required?
         log.info(log_key) { "Extracting `#{safe_downloaded_file}' to `#{safe_project_dir}'" }
         extract
       else
-        log.info(log_key) { "`#{safe_downloaded_file}' is not an archive - copying to `#{safe_project_dir}'" }
+        if extract_required?
+          log.info(log_key) { "`#{safe_downloaded_file}' has extraction disabled - copying to `#{safe_project_dir}'" }
+        else
+          log.info(log_key) { "`#{safe_downloaded_file}' is not an archive - copying to `#{safe_project_dir}'" }
+        end
 
         if File.directory?(downloaded_file)
           # If the file itself was a directory, copy the whole thing over. This