Awesome
RQRCodeCore
rqrcode_core
is a library for encoding QR Codes in pure Ruby. It has a simple interface with all the standard qrcode options. It was originally adapted in 2008 from a Javascript library by Kazuhiko Arase.
Features:
rqrcode_core
is a Ruby only library. It requires no 3rd party libraries. Just Ruby!- It is an encoding library. You can't decode QR Codes with it.
- The interface is simple and assumes you just want to encode a string into a QR Code, but also allows for encoding multiple segments.
- QR Code is trademarked by Denso Wave inc.
- Minimum Ruby version is
>= 3.0.0
rqrcode_core
is the basis of the popular rqrcode
gem [https://github.com/whomwah/rqrcode]. This gem allows you to generate different renderings of your QR Code, including png
, svg
and ansi
.
Installation
Add this line to your application's Gemfile:
gem "rqrcode_core"
And then execute:
$ bundle
Or install it yourself as:
$ gem install rqrcode_core
Basic Usage
$ require "rqrcode_core"
$ qr = RQRCodeCore::QRCode.new("https://kyan.com")
$ puts qr.to_s
Output:
xxxxxxx x x x x x xx xxxxxxx
x x xxx xxxxxx xxx x x
x xxx x xxxxx x xx x xxx x
... etc
Multiple Encoding Support
$ require "rqrcode_core"
$ qr = RQRCodeCore::QRCode.new([
{data: "byteencoded", mode: :byte_8bit},
{data: "A1" * 100, mode: :alphanumeric},
{data: "1" * 500, mode: :number}
])
This will create a QR Code with byte encoded, alphanumeric and number segments. Any combination of encodings/segments will work provided it fits within size limits.
Doing your own rendering
require "rqrcode_core"
qr = RQRCodeCore::QRCode.new("https://kyan.com")
qr.modules.each do |row|
row.each do |col|
print col ? "#" : " "
end
print "\n"
end
Options
The library expects a string or array (for multiple encodings) to be parsed in, other args are optional.
data - the string or array you wish to encode
size - the size (integer) of the QR Code (defaults to smallest size needed to encode the string)
max_size - the max_size (Integer) of the QR Code (default RQRCodeCore::QRUtil.max_size)
level - the error correction level, can be:
* Level :l 7% of code can be restored
* Level :m 15% of code can be restored
* Level :q 25% of code can be restored
* Level :h 30% of code can be restored (default :h)
mode - the mode of the QR Code (defaults to alphanumeric or byte_8bit, depending on the input data, only used when data is a string):
* :number
* :alphanumeric
* :byte_8bit
* :kanji
Example
RQRCodeCore::QRCode.new("http://kyan.com", size: 2, level: :m, mode: :byte_8bit)
Development
Tests
You can run the test suite using:
$ ./bin/setup
$ rake
or try the project from the console with:
$ ./bin/console
Linting
The project uses standardrb and can be run with:
$ ./bin/setup
$ rake standard # check
$ rake standard:fix # fix
Experimental
On 64 bit systems when generating lots of QR Codes the lib will consume more memory than on a 32 bit systems during the internal "right shift zero fill" steps (this is expected). In tests though, it's shown that by forcing the lib to think you're on a 32 systems greatly reduces the memory footprint. This could of course have undesired consequences too! but if you're happy to try, you can use the RQRCODE_CORE_ARCH_BITS
ENV to make this change. e.g RQRCODE_CORE_ARCH_BITS=32
.
Contributing
Bug reports and pull requests are welcome on GitHub at https://github.com/whomwah/rqrcode_core.
License
The gem is available as open source under the terms of the MIT License.