SimpleHL7Parser

simple_hl7_parser is a gem to parse HL7 text into ruby objects, optimized for developer happiness.

Installation

Add this line to your application's Gemfile:

gem 'simple_hl7_parser'

And then execute:

$ bundle

Or install it yourself as:

$ gem install simple_hl7_parser

Usage

SimpleHL7Parser::HL7.parse parses an HL7 string, returning a SimpleHL7Parser::HL7Message object. The returned object will respond to any message for a segment it contains with an array of matching segments. Each segment in the array in turn responds to messages based on standard HL7 element definitions.

Example:

hl7_string = "MSH|^~\\&|GHH LAB|ELAB-3|GHH OE|BLDG4|200202150930||ORU^R01|CNTRL-3456|P|2.4\nPID|||555-44-4444||EVERYWOMAN^EVE^E^^^^L|JONES|19620320|F|||153 FERNWOOD DR.^^STATESVILLE^OH^35292||(206)3345232|(206)752-121||||AC555444444||67-A4335^OH^20030520\nOBR|1|845439^GHH OE|1045813^GHH LAB|15545^GLUCOSE|||200202150730|||||||||555-55-5555^PRIMARY^PATRICIA P^^^^MD^^|||||||||F||||||444-44-4444^HIPPOCRATES^HOWARD H^^^^MD\nOBX|1|SN|1554-5^GLUCOSE^POST 12H CFST:MCNC:PT:SER/PLAS:QN||^182|mg/dl|70_105|H|||F"

msg = SimpleHL7Parser::HL7.parse(hl7_string)
msg.msh.first.message_type             #=> "ORU^R01"
msg.obr.first.universal_service_id     #=> "15545^GLUCOSE"
msg.obx.first.obr.universal_service_id #=> "15545^GLUCOSE"
msg.obx.first.observation_identifier   #=> "1554-5^GLUCOSE^POST 12H CFST:MCNC:PT:SER/PLAS:QN"
msg.obx.first.observation_value        #=> "^182"
msg.obx.first.units                    #=> "mg/dl"

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/sufyanadam/simple_hl7_parser. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.

Adding support for a HL7 Segment

Just create a class under the SimpleHL7Parser module namespace called XXXSegment (where XXX is a segment name, such as PID), include the Segment module and define a column map. That's it! It's that simple; hence the name SimpleHL7Parser.

The column map is a map of segment_attribute => position_number. For example, the placer_order_number is the third element in the OBR segment. So the column map would define {placer_order_number: 2}. The segment_attribute part of the column map becomes the name of the function you can call to retrieve the value of the attribute at the position it maps to.

The example below demonstrates how SimpleHL7Parser currently supports parsing the OBR HL7 segment in Ruby:

Example:

# Extending SimpleHL7Parser to support another
# HL7 Segment
require 'simple_hl7_parser/segments/segment'

module SimpleHL7Parser
  class OBRSegment
    include Segment

    COLUMN_MAP = {
      set_id:  1,
      placer_order_number:  2,
      filler_order_number:  3,
      universal_service_id:  4,
      priority:  5,
      requested_date_time:  6,
      observation_date_time:  7,
      observation_end_date_time:  8,
    }
  end
end

After adding support for a new segment, add a test that demonstrates it works correctly and make a pull request :)

License

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