Introduction

A PHP-based HL7 v2.x Parsing, Generation and Sending library, inspired from the famous Perl Net-HL7 package.

Installation

composer require aranyasen/hl7

Usage

Parsing

// Create a Message object from a HL7 string
$msg = new Message("MSH|^~\\&|1|\rPID|||abcd|\r"); // Either \n or \r can be used as segment endings
$pid = $msg->getSegmentByIndex(1);
echo $pid->getField(3); // prints 'abcd'
echo $msg->toString(true); // Prints entire HL7 string

Creating new messages

// Create an empty Message object, and populate MSH and PID segments... 
$msg = new Message();
$msh = new MSH();
$msg->addSegment($msh); // Message is: "MSH|^~\&|||||20171116140058|||2017111614005840157||2.3|\n"

// Create any custom segment
$abc = new Segment('ABC');
$abc->setField(1, 'xyz');
$abc->setField(4, ['']); // Set an empty field at 4th position. 2nd and 3rd positions will be automatically set to empty
$msg->setSegment($abc, 1); // Message is now: "MSH|^~\&|||||20171116140058|||2017111614005840157||2.3|\nABC|xyz|\n"

// Create a defined segment (To know which segments are defined in this package, look into Segments/ directory)
// Advantages of defined segments over custom ones (shown above) are 1) Helpful setter methods, 2) Auto-incrementing segment index 
$pid = new PID(); // Automatically creates PID segment, and adds segment index at PID.1
$pid->setPatientName([$lastname, $firstname, $middlename, $suffix]); // Use a setter method to add patient's name at standard position (PID.5)
$pid->setField('abcd', 5); // Apart from standard setter methods, you can manually set a value at any position too
unset $pid; // Destroy the segment and decrement the id number. Useful when you want to discard a segment.  

// Create a segment with empty sub-fields retained
$msg = new Message("MSH|^~\\&|1|\rPV1|1|O|^AAAA1^^^BB|", null, true); // Third argument 'true' forces to keep all sub fields
$pv1 = $msg->getSegmentByIndex(1);
$fields = $pv1->getField(3); // $fields is ['', 'AAAA1', '', '', 'BB']

// Create/send message with segment-ending bar character (|) removed
$msg = new Message("MSH|^~\\&|1|\nABC|||xxx\n", ['SEGMENT_ENDING_BAR' => false]);
$msg->toString(true); // Returns "MSH|^~\&|1\nABC|||xxx\n"
(new Connection($ip, $port))->send($msg); // Sends the message without ending bar-characters (details on Connection below) 

// Specify custom values for separators, HL7 version etc.
$msg = new Message("MSH|^~\\&|1|\rPV1|1|O|^AAAA1^^^BB|", ['SEGMENT_SEPARATOR' => '\r\n', 'HL7_VERSION' => '2.3']);

Send messages to remote listeners

$ip = '127.0.0.1'; // An IP
$port = '12001'; // And Port where a HL7 listener is listening
$message = new Message($hl7String); // Create a Message object from your HL7 string

// Create a Socket and get ready to send message. Optionally add timeout in seconds as 3rd argument (default: 10 sec)
$connection = new Connection($ip, $port);
$response = $connection->send($message); // Send to the listener, and get a response back
echo $reponse->toString(true); // Prints ACK from the listener

ACK

Handle ACK message returned from a remote HL7 listener...

$ack = (new Connection($ip, $port))->send($message); // Send a HL7 to remote listener
$returnString = $ack->toString(true);
if (strpos($returnString, 'MSH') === false) {
    echo "Failed to send HL7 to 'IP' => $ip, 'Port' => $port";
}
$msa = $ack->getSegmentsByName('MSA')[0];
$ackCode = $msa->getAcknowledgementCode();
if ($ackCode[1] === 'A') {
    echo "Recieved ACK from remote\n";
}
else {
    echo "Recieved NACK from remote\n";
    echo "Error text: " . $msa->getTextMessage()
}

APIs

Visit docs\README for details on available APIs

All segment level getter/setter APIs can be used in two ways -

• If a position index isn't provided as argument (1st argument for getters, 2nd for setters), a standard index is used.
  $pid->setPatientName('John Doe') -> Set patient name at position 5 as per HL7 v2.3 standard
  $pid->getPatientAddress() -> Get patient address from standard 11th position

• To use a custom position index, provide it in the argument:
  $pid->setPatientName('John Doe', 6) -> Set patient name at 6th position in PID segment
  $pid->getPatientAddress(12) -> Get patient address from 12th position

TODOs

• Data Validation
• Search by regex and return segment/field/index
• Define more segments