Class: HL7::Message

Inherits:
Object
  • Object
show all
Includes:
Enumerable
Defined in:
lib/ruby-hl7.rb

Overview

Ruby Object representation of an hl7 2.x message the message object is actually a “smart” collection of hl7 segments

Examples

Creating a new HL7 message

# create a message
msg = HL7::Message.new

# create a MSH segment for our new message
msh = HL7::Message::Segment::MSH.new
msh.recv_app = "ruby hl7"
msh.recv_facility = "my office"
msh.processing_id = rand(10000).to_s

msg << msh # add the MSH segment to the message

puts msg.to_s # readable version of the message

puts msg.to_hl7 # hl7 version of the message (as a string)

puts msg.to_mllp # mllp version of the message (as a string)

Parse an existing HL7 message 

raw_input = open( "my_hl7_msg.txt" ).readlines
msg = HL7::Message.new( raw_input )

puts "message type: %s" % msg[:MSH].message_type

Defined Under Namespace

Classes: Segment

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(raw_msg = nil) ⇒ Message

setup a new hl7 message

raw_msg

is an optional object containing an hl7 message it can either be a string or an Enumerable object



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# File 'lib/ruby-hl7.rb', line 83

def initialize( raw_msg=nil )
  @segments = []
  @segments_by_name = {}
  @item_delim = "^"
  @element_delim = '|' 
  @segment_delim = "\r"

  parse( raw_msg ) if raw_msg
end

Instance Attribute Details

#element_delim ⇒ Object (readonly)

Returns the value of attribute element_delim.



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# File 'lib/ruby-hl7.rb', line 76

def element_delim
  @element_delim
end

#item_delim ⇒ Object (readonly)

Returns the value of attribute item_delim.



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# File 'lib/ruby-hl7.rb', line 77

def item_delim
  @item_delim
end

#segment_delim ⇒ Object (readonly)

Returns the value of attribute segment_delim.



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# File 'lib/ruby-hl7.rb', line 78

def segment_delim
  @segment_delim
end

Class Method Details

.parse(inobj) ⇒ Object

parse a String or Enumerable object into an HL7::Message if possible

  • returns a new HL7::Message if successful



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# File 'lib/ruby-hl7.rb', line 151

def self.parse( inobj )
  ret = HL7::Message.new
  ret.parse( inobj )
  ret
end

Instance Method Details

#<<(value) ⇒ Object

add a segment to the message

  • will force auto set_id sequencing for segments containing set_id’s



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# File 'lib/ruby-hl7.rb', line 138

def <<( value )
  unless ( value && value.kind_of?(HL7::Message::Segment) )
    raise HL7::Exception.new( "attempting to append something other than an HL7 Segment" ) 
  end

  (@segments ||= []) << value
  name = value.class.to_s.gsub("HL7::Message::Segment::", "").to_sym
  (@segments_by_name[ name ] ||= []) << value
  sequence_segments # let's auto-set the set-id as we go
end

#[](index) ⇒ Object

access a segment of the message

index

can be a Range, Fixnum or anything that responds to to_sym



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# File 'lib/ruby-hl7.rb', line 96

def []( index )
  ret = nil

  if index.kind_of?(Range) || index.kind_of?(Fixnum)
    ret = @segments[ index ]
  elsif (index.respond_to? :to_sym)
    ret = @segments_by_name[ index.to_sym ]
    ret = ret.first if ret.length == 1
  end

  ret
end

#[]=(index, value) ⇒ Object

modify a segment of the message

index

can be a Range, Fixnum or anything that responds to to_sym

value

an HL7::Message::Segment object



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# File 'lib/ruby-hl7.rb', line 113

def []=( index, value )
  unless ( value && value.kind_of?(HL7::Message::Segment) )
    raise HL7::Exception.new( "attempting to assign something other than an HL7 Segment" ) 
  end

  if index.kind_of?(Range) || index.kind_of?(Fixnum)
    @segments[ index ] = value
  else
    (@segments_by_name[ index.to_sym ] ||= []) << value
  end
end

#each ⇒ Object

yield each segment in the message



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# File 'lib/ruby-hl7.rb', line 171

def each # :yeilds: segment
  return unless @segments
  @segments.each { |s| yield s }
end

#index(value) ⇒ Object

return the index of the value if it exists, nil otherwise

value

is expected to be a string



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# File 'lib/ruby-hl7.rb', line 127

def index( value )
  return nil unless (value && value.respond_to?(:to_sym))
  
  segs = @segments_by_name[ value.to_sym ]
  return nil unless segs

  @segments.index( segs.to_a.first )
end

#parse(inobj) ⇒ Object

parse the provided String or Enumerable object into this message



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# File 'lib/ruby-hl7.rb', line 158

def parse( inobj )
  unless inobj.kind_of?(String) || inobj.respond_to?(:each)
    raise HL7::ParseError.new
  end

  if inobj.kind_of?(String)
      parse_string( inobj )
  elsif inobj.respond_to?(:each)
      parse_enumerable( inobj )
  end
end

#sequence_segments(base = nil) ⇒ Object

auto-set the set_id fields of any message segments that provide it and have more than one instance in the message



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# File 'lib/ruby-hl7.rb', line 194

def sequence_segments(base=nil)
  last = nil
  segs = @segments
  segs = base.children if base

  segs.each do |s|
    if s.kind_of?( last.class ) && s.respond_to?( :set_id )
      if (last.set_id == "" || last.set_id == nil)
        last.set_id = 1
      end
      s.set_id = last.set_id.to_i + 1
    end

    if s.respond_to?(:children)
      sequence_segments( s )
    end

    last = s
  end
end

#to_hl7 ⇒ Object

provide a HL7 spec version of the message



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# File 'lib/ruby-hl7.rb', line 182

def to_hl7
  @segments.join( @segment_delim )
end

#to_mllp ⇒ Object

provide the HL7 spec version of the message wrapped in MLLP



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# File 'lib/ruby-hl7.rb', line 187

def to_mllp
  pre_mllp = to_hl7
  "\x0b" + pre_mllp + "\x1c\r"
end

#to_s ⇒ Object

provide a screen-readable version of the message



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# File 'lib/ruby-hl7.rb', line 177

def to_s                         
  @segments.join( '\n' )
end