CV Rake Task to run a list of druids in a csv

Rake task to Rakefile: cv_druid_list which takes a file_path
parameter.

Checksum.validate_list_of_druids method which iterates over each
druid in the csv and invokes the already written method:
Checksum.validate_druid

RSpec test where Checksum.validate_druid is called once per druid

Update README with usage information and assumptions

README.md

@@ -200,12 +200,19 @@ RAILS_ENV=production bundle exec rake cv_all_endpoints[profile]
 ```
 this will generate a log at, for example, `log/profile_cv_validate_disk_all_endpoints2018-01-01T14:25:31-flat.txt`
 
-### One druid at a time
+#### Single Druid
 - Without profiling:
 ```sh
 RAILS_ENV=production bundle exec rake cv_druid[bz514sm9647]
 ```
 
+#### Druid List
+- Give the file path of the csv as the parameter. The first column of the csv should contain druids, without the prefix, and contain no headers.
+- Without profiling:
+```sh
+RAILS_ENV=production bundle exec rake cv_druid_list[/file/path/to/your/csv/druid_list.csv]
+
+```
 ## Development
 
 ### Running Tests

Rakefile

@@ -224,3 +224,11 @@ task :cv_druid, [:druid] => [:environment] do |_t, args|
   # exit with non-zero status if any of the pres copies failed checksum validation
   exit 1 if cv_results_lists.detect { |aud_res| !aud_res.contains_result_code?(AuditResults::MOAB_CHECKSUM_VALID) }
 end
+
+desc "Fire off checksum validation on a list of druids"
+task :cv_druid_list, [:file_path] => [:environment] do |_t, args|
+  druid_list_file_path = args[:file_path]
+  puts "#{Time.now.utc.iso8601} Checksum Validation on the list of druids from #{druid_list_file_path} has started"
+  Checksum.validate_list_of_druids(druid_list_file_path)
+  puts "#{Time.now.utc.iso8601} Checksum Validation on the list of druids from #{druid_list_file_path} has finished."
+end

lib/audit/checksum.rb

@@ -1,4 +1,5 @@
 require 'profiler.rb'
+require 'csv'
 
 # Checksum validator code
 class Checksum
@@ -57,4 +58,11 @@ def self.validate_druid(druid)
   ensure
     logger.info "#{Time.now.utc.iso8601} CV validate_druid ended for #{druid}"
   end
+
+  # assumes that the list of druids is in column 1, and has no header.
+  def self.validate_list_of_druids(druid_list_file_path)
+    CSV.foreach(druid_list_file_path) do |druid|
+      Checksum.validate_druid(druid.join)
+    end
+  end
 end

spec/lib/audit/checksum_spec.rb

@@ -126,4 +126,17 @@
       expect(checksum_results.contains_result_code?(AuditResults::MOAB_CHECKSUM_VALID)).to eq true
     end
   end
+
+  describe ".validate_list_of_druids" do
+    include_context 'fixture moabs in db'
+
+    it 'calls Checksum.validate_druid once per druid' do
+      csv_file_path = 'spec/fixtures/druid_list.csv'
+      CSV.foreach(csv_file_path) do |row|
+        expect(described_class).to receive(:validate_druid).with(row.first)
+      end
+      described_class.validate_list_of_druids(csv_file_path)
+    end
+  end
+
 end