Merge branch '29-pseudonym-for-operator-on-pdf' into 'init19'

Resolve "Pseudonym for Operator on PDF"

Closes #29

See merge request !20

app/lib/pdfs/sample_pdf.rb

@@ -16,7 +16,7 @@ class SamplePdf < Prawn::Document
          text "submitted at: \ #{@sample.submitted_at}", size: 15, style: :bold
     elsif @sample.status=="measured"
        text "measured at: \ #{@sample.measured_at}",size: 15, style: :bold
-       text "measured by: \ #{@sample.operator_name}",size: 15, style: :bold
+       text "measured by: \ #{@sample.operator_link_id}",size: 15, style: :bold
     else
        text "created at: \ #{@sample.created_at}",size: 15, style: :bold
    end

app/lib/sample_pdf.rb

@@ -16,7 +16,7 @@ class SamplePdf < Prawn::Document
          text "submitted at: \ #{@sample.submitted_at}", size: 15, style: :bold
     elsif @sample.status=="measured"
        text "measured at: \ #{@sample.measured_at}",size: 15, style: :bold
-       text "measured by: \ #{@sample.operator_name}",size: 15, style: :bold
+       text "measured by: \ #{@sample.operator_link_id}",size: 15, style: :bold
     else
        text "created at: \ #{@sample.created_at}",size: 15, style: :bold
    end

app/models/sample.rb

@@ -20,6 +20,10 @@ class Sample < ApplicationRecord
 
   REG = /(#{ELEMENTS.keys.map(&:to_s).sort.reverse.join("|")})(\d*)/
 
+  def operator_link_id
+    User.find_by(name: operator_name)&.id
+  end
+
   def formatted_calculation
     self.calculation
     keys = ( PREDEF_ELEMENTS+(self.calculation.keys  - PREDEF_ELEMENTS) ).uniq