StrMasker

A simple and flexible Ruby gem for masking portions of strings with customizable characters.

Add this line to your application's Gemfile:

gem 'str_masker'

And then execute:

$ bundle install

Or install it yourself as:

$ gem install str_masker

StrMasker provides a simple interface for masking strings with asterisks or any custom character.

require 'str_masker'

# Mask entire string (default behavior)
StrMasker.mask_string("password")
#=> "********"

# Mask middle characters, keeping first and last
StrMasker.mask_string("password", from: 1, to: -2)
#=> "p******d"

# Mask from beginning, keeping last character
StrMasker.mask_string("secret", from: 0, to: -2)
#=> "*****t"

# Mask from second character to end
StrMasker.mask_string("confidential", from: 1, to: -1)
#=> "c***********"

# Use a different character for masking
StrMasker.mask_string("password", from: 1, to: -2, char: '#')
#=> "p######d"

StrMasker.mask_string("email@example.com", from: 2, to: -5, char: 'X')
#=> "emXXXXXXXXX.com"

# Returns nil for nil input
StrMasker.mask_string(nil)
#=> nil

# Returns original string if no masking is needed
StrMasker.mask_string("ab", from: 1, to: -2)
#=> "ab"

# Empty string
StrMasker.mask_string("")
#=> ""

Masks a portion of a string with the specified character.

• val (String, nil): The string to mask. Returns nil if input is nil.
• from (Integer, optional): Starting position for masking (inclusive). Must be non-negative. Default: 0.
• to (Integer, optional): Ending position for masking (must be negative, counts from end). Default: -1.
• char (String, optional): The character to use for masking. Must be a single character. Default: '*'.

• String or nil: The masked string, or nil if input was nil.

• ArgumentError: If from is negative, to is non-negative, or char is not a single character.

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and the created tag, and push the .gem file to rubygems.org.

Bug reports and pull requests are welcome on GitHub at https://github.com/MichalZaporski/str_masker.

The gem is available as open source under the terms of the MIT License.