HL7py 1.0

HL7 message parser

HL7py
=====
The MIT License

Copyright (c) 2012 Nicholas Orlowski

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
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=====



A parser for the HL7 Health data interchange format written in python. Provides
attribute-like access to correct datatypes and provides the ability to construct HL7
messages from dictionaries.

The HL7 transport protocol is a confusing mess of pipes and carriage returns. This package
provides easy Pythonic access to attributes within a message. There is much domain
knowledge of segments names and field names, but what follows are some basic examples of
syntax and usage.



Here is a sample message from http://www.coast2coastinformatics.com/user/ADTA08_examples-110106.pdf

MSH|^~\&|AccMgr|1|||20050110045504||ADT^A01|599102|P|2.3|||
EVN|A01|20050110045502|||||
PID|1||10006579^^^1^MRN^1||DUCK^DONALD^D||19241010|M||1|111 DUCK ST^^FOWL^CA^999990000^^M|1|8885551212|8885551212|1|2||40007716^^^AccMgr^VN^1|123121234|||||||||||NO NK1|1|DUCK^HUEY|SO|3583 DUCK RD^^FOWL^CA^999990000|8885552222||Y||||||||||||||
PV1|1|I|PREOP^101^1^1^^^S|3|||37^DISNEY^WALT^^^^^^AccMgr^^^^CI|||01||||1|||37^DISNEY^WALT^^^^^^AccMgr^^^^CI|2|40007716^^^AccMgr^VN|4|||||||||||||||||||1||G|||20050110045253||||||
GT1|1|8291|DUCK^DONALD^D||111^DUCK ST^^FOWL^CA^999990000|8885551212||19241010|M||1|123121234||||#Cartoon Ducks Inc|111^DUCK ST^^FOWL^CA^999990000|8885551212||PT| DG1|1|I9|71596^OSTEOARTHROS NOS-L/LEG ^I9|OSTEOARTHROS NOS-L/LEG ||A|
IN1|1|MEDICARE|3|MEDICARE|||||||Cartoon Ducks Inc|19891001|||4|DUCK^DONALD^D|1|19241010|111^DUCK ST^^FOWL^CA^999990000|||||||||||||||||123121234A||||||PT|M|111 DUCK ST^^FOWL^CA^999990000|||||8291
IN2|1||123121234|Cartoon Ducks Inc|||123121234A|||||||||||||||||||||||||||||||||||||||||||||||||||||||||8885551212 IN1|2|NON-PRIMARY|9|MEDICAL MUTUAL CALIF.|PO BOX 94776^^HOLLYWOOD^CA^441414776||8003621279|PUBSUMB|||Cartoon Ducks Inc||||7|DUCK^DONALD^D|1|19241010|111 DUCK ST^^FOWL^CA^999990000|||||||||||||||||056269770||||||PT|M|111^DUCK ST^^FOWL^CA^999990000|||||8291 IN2|2||123121234|Cartoon Ducks Inc||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||8885551212
IN1|3|SELF PAY|1|SELF PAY|||||||||||5||1


(Lines not wrapped for emotional effect)


=================DATA ACCESS EXAMPLES============

You will be able to use syntax like

1. 'SEG.some_attribute.data' to access either a dictionary (if that field has subfields)
or a value parsed to the correct datatype, e.g. datetime or numeric.
2. 'SEG.some_attribute.hl7' to have the message construct the HL7 equivalent of that
attribute and all of its following segments and subsegments.

3. 'SEG.some_attribute.some_timestamp.data = datetime.datetime.now()' allows you to set
the value of a specific note/segment. See examples in the tests.


Examples:

from HL7py import parser
my_message = parser.parse(incoming_str)
my_message.PID.pat_name.data
{'family_name':'DUCK','give_name':'DONALD','middle_name':'D'}
my_message.PID.pat_name.family_name.hl7
'DUCK'
my_message.IN1[0].ins_company_name.hl7
'MEDICARE'
my_message.IN1[0].ins_company_name.data
'MEDICARE'
my_message.IN1[1].ins_company_name.hl7
'SELF PAY'
my_message.IN1_list
[IN1,IN1]
for ins in IN1_list:
print ins.ins_company_name.hl7
'MEDICARE'
'SELFPAY




The NTE section is a special case. NTE sections can come after any other section and
are assembled into the .note attribute for a segment.



PID|1|123456789|112233|1234567|Test^Patient||19820620|F|||123 Fake St.^^SumCity^ST^12345-||[phone]||||||
ORC|RE|29117637990^LAB|291176379902012^LAB||||||201210170000|||1366445686^Doctor^M^^^^^N
OBR|1|29117637990^LAB|291176379902012^LAB|001321^Iron and TIBC^L|||201210171632|||||||201210171934||||M542856833||29117637990||201210180743|||F
OBX|1|NM|001347^Iron Bind.Cap.(TIBC)^L||476|ug/dL|250-450|H||N|F|19840622||201210180726|BN
OBX|2|NM|001348^UIBC^L||462|ug/dL|150-375|H||N|F|19940518||201210180726|BN
NTE|1|L|Results confirmed on
NTE|2|L|dilution.

The following would occur:

print my_message.ORC.OBR.OBX_list[1].note
'Results confirmed on dilution'

=================MESSAGE CREATION EXAMPLES============
Messages are created by assembling Segments and adding them to a Message.
Here is an example of how our EMR, Ankhos, constructs an ADT/A08 message. The chart.to_dict()
method constructs a dictionary of the relevant fields from chart demographics, etc.

msg = Message()
msh_data= dict(
recv_app={'app_name': 'Their App'},
send_app={'app_name': 'ANKHOS'},
msg_type=dict(message_code='ADT',
event_code='A08'),
accept_ack_type='AL',
application_ack_type='AL',
proc_id='P',
version='2.3',
msg_ctl_id=control_id,
encoding_chars='^~\&',
timestamp=datetime.datetime.now())
MSH = Segment(code='MSH',data=msh_data)
evn_data = dict(event_code=event_code,timestamp=dict(time=datetime.datetime.now(),
resolution='S'))
EVN = Segment(code='EVN',data=evn_data)
PID = Segment(code='PID',data=chart.to_dict())
pv1_data = {...}
PV1 = Segment(code='PV1',data=pv1_data)
msg.add_segments([MSH,EVN,PID,PV1])

#Voila!
print msg.hl7


As long as the data dictionaries follow the signatures in the HL7fields.py specification,
the Segments should be constructed correctly. There are a LOT of HL7 specified segments
but only a few in the include HL7fields.py file. We simply haven't had a use for most of them
yet but if we do, I will be sure to update the HL7fields specification dictionary.


Current limitations:
1. The ADD operation is not supported. (very low priority)
2. Intra-field repetition is not yet supported
3. The tests included are only smoke tests to make sure fundamental things haven't broken!
HL7 is used in life-critical systems. Again. Please Please Please test your own software!
More real tests will be added when time allows.