Get names of all files from a folder with Ruby

Question

I want to get all file names from a folder using Ruby.

Answer 1

You also have the shortcut option of

Dir["/path/to/search/*"]

and if you want to find all Ruby files in any folder or sub-folder:

Dir["/path/to/search/**/*.rb"]

Answer 2

Dir.entries(folder)

example:

Dir.entries(".")

Source: http://ruby-doc.org/core/classes/Dir.html#method-c-entries

Answer 3

The following snippets exactly shows the name of the files inside a directory, skipping subdirectories and ".", ".." dotted folders:

Dir.entries("your/folder").select { |f| File.file? File.join("your/folder", f) }

Answer 4

To get all files (strictly files only) recursively:

Dir.glob('path/**/*').select { |e| File.file? e }

Or anything that's not a directory (File.file? would reject non-regular files):

Dir.glob('path/**/*').reject { |e| File.directory? e }

Alternative Solution

Using Find#find over a pattern-based lookup method like Dir.glob is actually better. See this answer to "One-liner to Recursively List Directories in Ruby?".

Answer 5

This works for me:

If you don't want hidden files[1], use Dir[]:

# With a relative path, Dir[] will return relative paths 
# as `[ './myfile', ... ]`
#
Dir[ './*' ].select{ |f| File.file? f } 

# Want just the filename?
# as: [ 'myfile', ... ]
#
Dir[ '../*' ].select{ |f| File.file? f }.map{ |f| File.basename f }

# Turn them into absolute paths?
# [ '/path/to/myfile', ... ]
#
Dir[ '../*' ].select{ |f| File.file? f }.map{ |f| File.absolute_path f }

# With an absolute path, Dir[] will return absolute paths:
# as: [ '/home/../home/test/myfile', ... ]
#
Dir[ '/home/../home/test/*' ].select{ |f| File.file? f }

# Need the paths to be canonical?
# as: [ '/home/test/myfile', ... ]
#
Dir[ '/home/../home/test/*' ].select{ |f| File.file? f }.map{ |f| File.expand_path f }

Now, Dir.entries will return hidden files, and you don't need the wildcard asterix (you can just pass the variable with the directory name), but it will return the basename directly, so the File.xxx functions won't work.

# In the current working dir:
#
Dir.entries( '.' ).select{ |f| File.file? f }

# In another directory, relative or otherwise, you need to transform the path 
# so it is either absolute, or relative to the current working dir to call File.xxx functions:
#
home = "/home/test"
Dir.entries( home ).select{ |f| File.file? File.join( home, f ) }

[1] .dotfile on unix, I don't know about Windows

Answer 6

In Ruby 2.5 you can now use Dir.children. It gets filenames as an array except for "." and ".."

Example:

Dir.children("testdir")   #=> ["config.h", "main.rb"]

http://ruby-doc.org/core-2.5.0/Dir.html#method-c-children

Answer 7

Personally, I found this the most useful for looping over files in a folder, forward looking safety:

Dir['/etc/path/*'].each do |file_name|
  next if File.directory? file_name 
end

Answer 8

This is a solution to find files in a directory:

files = Dir["/work/myfolder/**/*.txt"]

files.each do |file_name|
  if !File.directory? file_name
    puts file_name
    File.open(file_name) do |file|
      file.each_line do |line|
        if line =~ /banco1/
          puts "Found: #{line}"
        end
      end
    end
  end
end

Answer 9

this code returns only filenames with their extension (without a global path)

Dir.children("/path/to/search/")

=> [file_1.rb, file_2.html, file_3.js]

Answer 10

While getting all the file names in a directory, this snippet can be used to reject both directories [., ..] and hidden files which start with a .

files = Dir.entries("your/folder").reject {|f| File.directory?(f) || f[0].include?('.')}

Answer 11

This is what works for me:

Dir.entries(dir).select { |f| File.file?(File.join(dir, f)) }

Dir.entries returns an array of strings. Then, we have to provide a full path of the file to File.file?, unless dir is equal to our current working directory. That's why this File.join().

Answer 12

Dir.new('/home/user/foldername').each { |file| puts file }

Answer 13

You may also want to use Rake::FileList (provided you have rake dependency):

FileList.new('lib/*') do |file|
  p file
end

According to the API:

FileLists are lazy. When given a list of glob patterns for possible files to be included in the file list, instead of searching the file structures to find the files, a FileList holds the pattern for latter use.

https://docs.ruby-lang.org/en/2.1.0/Rake/FileList.html

Answer 14

One simple way could be:

dir = './' # desired directory
files = Dir.glob(File.join(dir, '**', '*')).select{|file| File.file?(file)}

files.each do |f|
    puts f
end

Answer 15

When loading all names of files in the operating directory you can use

Dir.glob("*)

This will return all files within the context that the application is running in (Note for Rails this is the top level directory of the application)

You can do additional matching and recursive searching found here https://ruby-doc.org/core-2.7.1/Dir.html#method-c-glob

Answer 16

def get_path_content(dir)
  queue = Queue.new
  result = []
  queue << dir
  until queue.empty?
    current = queue.pop
    Dir.entries(current).each { |file|
      full_name = File.join(current, file)
      if not (File.directory? full_name)
        result << full_name
      elsif file != '.' and file != '..'
          queue << full_name
      end
    }
  end
  result
end

returns file's relative paths from directory and all subdirectories

Answer 17

If you want get an array of filenames including symlinks, use

Dir.new('/path/to/dir').entries.reject { |f| File.directory? f }

or even

Dir.new('/path/to/dir').reject { |f| File.directory? f }

and if you want to go without symlinks, use

Dir.new('/path/to/dir').select { |f| File.file? f }

As shown in other answers, use Dir.glob('/path/to/dir/**/*') instead of Dir.new('/path/to/dir') if you want to get all the files recursively.

Answer 18

In addition to the suggestions in this thread, I wanted to mention that if you need to return dot files as well (.gitignore, etc), with Dir.glob you would need to include a flag as so: Dir.glob("/path/to/dir/*", File::FNM_DOTMATCH) By default, Dir.entries includes dot files, as well as current a parent directories.

For anyone interested, I was curious how the answers here compared to each other in execution time, here was the results against deeply nested hierarchy. The first three results are non-recursive:

       user     system      total        real
Dir[*]: (34900 files stepped over 100 iterations)
  0.110729   0.139060   0.249789 (  0.249961)
Dir.glob(*): (34900 files stepped over 100 iterations)
  0.112104   0.142498   0.254602 (  0.254902)
Dir.entries(): (35600 files stepped over 100 iterations)
  0.142441   0.149306   0.291747 (  0.291998)
Dir[**/*]: (2211600 files stepped over 100 iterations)
  9.399860  15.802976  25.202836 ( 25.250166)
Dir.glob(**/*): (2211600 files stepped over 100 iterations)
  9.335318  15.657782  24.993100 ( 25.006243)
Dir.entries() recursive walk: (2705500 files stepped over 100 iterations)
 14.653018  18.602017  33.255035 ( 33.268056)
Dir.glob(**/*, File::FNM_DOTMATCH): (2705500 files stepped over 100 iterations)
 12.178823  19.577409  31.756232 ( 31.767093)

These were generated with the following benchmarking script:

require 'benchmark'
base_dir = "/path/to/dir/"
n = 100
Benchmark.bm do |x|
  x.report("Dir[*]:") do
    i = 0
    n.times do
      i = i + Dir["#{base_dir}*"].select {|f| !File.directory? f}.length
    end
    puts " (#{i} files stepped over #{n} iterations)"
  end
  x.report("Dir.glob(*):") do
    i = 0
    n.times do
      i = i + Dir.glob("#{base_dir}/*").select {|f| !File.directory? f}.length
    end
    puts " (#{i} files stepped over #{n} iterations)"
  end
  x.report("Dir.entries():") do
    i = 0
    n.times do
      i = i + Dir.entries(base_dir).select {|f| !File.directory? File.join(base_dir, f)}.length
    end
    puts " (#{i} files stepped over #{n} iterations)"
  end
  x.report("Dir[**/*]:") do
    i = 0
    n.times do
      i = i + Dir["#{base_dir}**/*"].select {|f| !File.directory? f}.length
    end
    puts " (#{i} files stepped over #{n} iterations)"
  end
  x.report("Dir.glob(**/*):") do
    i = 0
    n.times do
      i = i + Dir.glob("#{base_dir}**/*").select {|f| !File.directory? f}.length
    end
    puts " (#{i} files stepped over #{n} iterations)"
  end
  x.report("Dir.entries() recursive walk:") do
    i = 0
    n.times do
      def walk_dir(dir, result)
        Dir.entries(dir).each do |file|
          next if file == ".." || file == "."

          path = File.join(dir, file)
          if Dir.exist?(path)
            walk_dir(path, result)
          else
            result << file
          end
        end
      end
      result = Array.new
      walk_dir(base_dir, result)
      i = i + result.length
    end
    puts " (#{i} files stepped over #{n} iterations)"
  end
  x.report("Dir.glob(**/*, File::FNM_DOTMATCH):") do
    i = 0
    n.times do
      i = i + Dir.glob("#{base_dir}**/*", File::FNM_DOTMATCH).select {|f| !File.directory? f}.length
    end
    puts " (#{i} files stepped over #{n} iterations)"
  end
end

The differences in file counts are due to Dir.entries including hidden files by default. Dir.entries ended up taking a bit longer in this case due to needing to rebuild the absolute path of the file to determine if a file was a directory, but even without that it was still taking consistently longer than the other options in the recursive case. This was all using ruby 2.5.1 on OSX.

Answer 19

if you create directories with spaces:

mkdir "a b"
touch "a b/c"

You don't need to escape the directory names, it will do it automatically:

p Dir["a b/*"] # => ["a b/c"]