error related to REXML

Question

I'm not sure it's REXML or ruby issue. But this is happening when I work with REXML.

The program below should access elements of each xml file in the directory.

#!/usr/bin/ruby -w

require 'rexml/document'
include REXML

p "Current directory was: " + Dir.pwd

Dir.chdir("/home/askar/xml_files1") {

    p "Now we're in: " + Dir.pwd

    if File.exist?(Dir.pwd)

        xml_files = Dir.glob("ShipmentRequest*.xml")

        Dir.foreach(Dir.pwd) do |file|

            xmlfile = File.new(file)
            xmldoc = Document.new(xmlfile)

        end

    else
        puts "It's empty"
    end

}

When I run:

ruby import_xml.rb

Errors:

"Current directory was: /home/askar/Dropbox/rails_studio/xml_to_mysql"
"Now we're in: /home/askar/xml_files1"
There're 6226 files in the folder...
/home/askar/.rvm/rubies/ruby-1.9.3-p429/lib/ruby/1.9.1/rexml/source.rb:148:in `read': Is a directory - . (Errno::EISDIR)
    from /home/askar/.rvm/rubies/ruby-1.9.3-p429/lib/ruby/1.9.1/rexml/source.rb:148:in `initialize'
    from /home/askar/.rvm/rubies/ruby-1.9.3-p429/lib/ruby/1.9.1/rexml/source.rb:14:in `new'
    from /home/askar/.rvm/rubies/ruby-1.9.3-p429/lib/ruby/1.9.1/rexml/source.rb:14:in `create_from'
    from /home/askar/.rvm/rubies/ruby-1.9.3-p429/lib/ruby/1.9.1/rexml/parsers/baseparser.rb:127:in `stream='
    from /home/askar/.rvm/rubies/ruby-1.9.3-p429/lib/ruby/1.9.1/rexml/parsers/baseparser.rb:116:in `initialize'
    from /home/askar/.rvm/rubies/ruby-1.9.3-p429/lib/ruby/1.9.1/rexml/parsers/treeparser.rb:9:in `new'
    from /home/askar/.rvm/rubies/ruby-1.9.3-p429/lib/ruby/1.9.1/rexml/parsers/treeparser.rb:9:in `initialize'
    from /home/askar/.rvm/rubies/ruby-1.9.3-p429/lib/ruby/1.9.1/rexml/document.rb:245:in `new'
    from /home/askar/.rvm/rubies/ruby-1.9.3-p429/lib/ruby/1.9.1/rexml/document.rb:245:in `build'
    from /home/askar/.rvm/rubies/ruby-1.9.3-p429/lib/ruby/1.9.1/rexml/document.rb:43:in `initialize'
    from import_xml.rb:20:in `new'
    from import_xml.rb:20:in `block (2 levels) in <main>'
    from import_xml.rb:17:in `foreach'
    from import_xml.rb:17:in `block in <main>'
    from import_xml.rb:8:in `chdir'
    from import_xml.rb:8:in `<main>'

When I comment out:

#xmldoc = Document.new(xmlfile)

it's not giving errors.

Folder /home/askar/xml_files1 contains only 3 xml files.

I'm using Linux Mint Nadia and

ruby -v
ruby 1.9.3p429 (2013-05-15 revision 40747) [x86_64-linux]

If you noticed, for some reason, error shows ruby 1.9.1. Is this an issue?

Why are you using REXML? It's fallen to the wayside as far as XML parsers go. I'd strongly recommend using [Nokogiri](http://nokogiri.org). It's much faster and full featured. — the Tin Man, May 31 '13 at 05:54
@the Tin Man, thanks for you precious advice. I'll have to check it out! :) — Askar, May 31 '13 at 06:06

score 2 · Accepted Answer · answered May 31 '13 at 04:15

2

I think @halfelf is correct here. The API docs say that Dir.foreach will iterate over every entry in the directory - and in Unix, that includes the two directories . and ...

A couple lines before your Dir.foreach call, you use glob to build an array of files called xml_files. What happens if you iterate over that in your loop instead?

answered May 31 '13 at 04:15

dpassage

5,423
3
25
53

I got the same errors when substitute "foreach" with "glob". I even create new folder and put only 3 files there, so I know there's no a directory. I simplified the code and it worked for me, because I commented out xmldoc = Document.new(xmlfile), but xmlfile = File.new(file) does work. Please see the post with the updated (simplified) code. – Askar May 31 '13 at 05:06
You're still not fixing the problem, which is this line: `Dir.foreach(Dir.pwd) do |file|`. Try replacing it with `xml_files.each do |file|` – dpassage May 31 '13 at 05:39

score 1 · Answer 2 · answered May 31 '13 at 03:36

1

Just a guess: Not everything returned by Dir.foreach(Dir.pwd) is a file that can be read. Some of them are directories.

answered May 31 '13 at 03:36

halfelf

9,737
13
54
63

I know there're only files. – Askar May 31 '13 at 03:46
You sure? what about add a `begin rescue` block around `File.new` to see which file cannot be opened? – halfelf May 31 '13 at 03:50
Yes. I've even created empty directory and checked. I've noticed it's giving errors for the line xmldoc = Document.new(xmlfile). When I commented out from this line up to the end of the block, it's not giving errors. So the key is: xmldoc = Document.new(xmlfile) – Askar May 31 '13 at 03:59

score 0 · Answer 3 · answered May 31 '13 at 06:06

Using Nokogiri, here's how I'd write this:

#!/usr/bin/ruby -w

require 'nokogiri'

DIRNAME = "/home/askar/xml_files1"

puts "Current directory is: #{ Dir.pwd }"
Dir.chdir(DIRNAME) do

  puts "Now in: #{ DIRNAME }"
  xml_files = Dir.glob("ShipmentRequest*.xml")

  if xml_files.empty?
    puts "#{ DIRNAME } is empty."
  else
    xml_files.each do |file|
      doc = Nokogiri::XML(open(file))
      # ... do something with the doc ...
    end
  end
end

error related to REXML

3 Answers3