add bibtex fetch and output to file using 'extract-bib'

bin/pdf-extract

@@ -22,6 +22,7 @@ resolvers = {
 
 outputs = {
   :xml => proc { :stdout },
+  :bib => proc { |f| File::basename(f.sub /\.[a-zA-Z0-9]+\Z/, "") + ".refs.bib" },
   :pdf => proc { |f| File::basename(f.sub /\.[a-zA-Z0-9]+\Z/, "") + ".mask.pdf" }
 }
 
@@ -31,6 +32,11 @@ commands = [
     :view => :xml,
     :description => "Extract objects as XML."
   },
+  {
+    :name => "extract-bib",
+    :view => :bib,
+    :description => "Extract resolved references in BibTeX format."
+  },
   {
     :name => "mark",
     :view => :pdf,

lib/pdf/extract.rb

@@ -11,6 +11,7 @@
 require_relative 'extract/references/resolved_references.rb'
 require_relative 'extract/view/pdf_view.rb'
 require_relative 'extract/view/xml_view.rb'
+require_relative 'extract/view/bib_view.rb'
 
 module PdfExtract
 
@@ -68,6 +69,7 @@ def self.init
 
     add_view :pdf, PdfView
     add_view :xml, XmlView
+    add_view :bib, BibView
   end
 
   init

lib/pdf/extract/references/resolve.rb

@@ -13,8 +13,9 @@ def self.find ref
       url = "http://search.labs.crossref.org/dois?q=#{CGI.escape(ref)}&rows=1"
       query = JSON.parse(open(url).read())
       unless query.nil?
-        resolved[:doi] = query[0]["doi"]
+        resolved[:doi] = query[0]["doi"].sub "http://dx.doi.org/",""
         resolved[:score] = query[0]["score"]
+        puts "Found DOI from Text: #{resolved[:doi]} (Score: #{resolved[:score]})"
       end
       resolved
     end

lib/pdf/extract/view/bib_view.rb

@@ -0,0 +1,48 @@
+require 'net/http'
+
+require_relative 'abstract_view'
+require_relative '../language'
+
+module PdfExtract
+  class BibView < AbstractView
+
+    def render options={}
+
+      bibs = []
+
+      objects.each_pair do |type, objs|
+        objs.each do |obj|
+
+          if obj.key? :doi and obj.key? :score
+
+            if obj[:score] > 1
+              url = "http://api.crossref.org/works/#{obj[:doi]}/transform/application/x-bibtex"
+              begin
+                bib = open(URI.encode(url)).read()
+              rescue URI::InvalidURIError
+                puts "DOI not a valid URL: #{obj[:doi]}"
+              rescue OpenURI::HTTPError
+                puts "DOI not found on CrossRef: #{obj[:doi]}"
+              else
+                puts "Found BibTeX from DOI: #{obj[:doi]}"
+                bibs << bib
+              end
+            end
+
+          else
+            raise "Must run extract-bib with --resolved_references flag"
+          end
+        end
+      end
+
+      bibs.join("\n")
+    end
+
+    def self.write render, filename
+      File.open filename, "w" do |file|
+        file.write render
+      end
+    end
+
+  end
+end