MLLP

Since Camel 2.17

Both producer and consumer are supported

The MLLP component is specifically designed to handle the nuances of the MLLP protocol and provide the functionality required by Healthcare providers to communicate with other systems using the MLLP protocol. The MLLP component provides a simple configuration URI, automated HL7 acknowledgment generation and automatic acknowledgement interrogation.

The MLLP protocol does not typically use a large number of concurrent TCP connections - a single active TCP connection is the normal case. Therefore, the MLLP component uses a simple thread-per-connection model based an standard Java Sockets. This keeps the implementation simple and eliminates the dependencies other than Camel itself.

The component supports the following:

  • A Camel consumer using a TCP Server

  • A Camel producer using a TCP Client

The MLLP component uses byte[] payloads, and relies on Camel Type Conversion to convert byte[] to other types.

Maven users will need to add the following dependency to their pom.xml for this component:

<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-mllp</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>

MLLP Options

The MLLP component supports 6 options, which are listed below.

Name Description Default Type

bridgeErrorHandler (consumer)

Allows for bridging the consumer to the Camel routing Error Handler, which mean any exceptions occurred while the consumer is trying to pickup incoming messages, or the likes, will now be processed as a message and handled by the routing Error Handler. By default the consumer will use the org.apache.camel.spi.ExceptionHandler to deal with exceptions, that will be logged at WARN or ERROR level and ignored.

false

boolean

lazyStartProducer (producer)

Whether the producer should be started lazy (on the first message). By starting lazy you can use this to allow CamelContext and routes to startup in situations where a producer may otherwise fail during starting and cause the route to fail being started. By deferring this startup to be lazy then the startup failure can be handled during routing messages via Camel’s routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing.

false

boolean

basicPropertyBinding (advanced)

Deprecated Whether the component should use basic property binding (Camel 2.x) or the newer property binding with additional capabilities

false

boolean

defaultCharset (advanced)

Set the default character set to use for byte to/from String conversions.

ISO-8859-1

Charset

logPhi (advanced)

Set the component to log PHI data.

true

Boolean

logPhiMaxBytes (advanced)

Set the maximum number of bytes of PHI that will be logged in a log entry.

5120

Integer

The MLLP endpoint is configured using URI syntax:

mllp:hostname:port

with the following path and query parameters:

Path Parameters (2 parameters):

Name Description Default Type

hostname

Required Hostname or IP for connection for the TCP connection. The default value is null, which means any local IP address

String

port

Required Port number for the TCP connection

int

Query Parameters (29 parameters):

Name Description Default Type

autoAck (common)

Enable/Disable the automatic generation of a MLLP Acknowledgement MLLP Consumers only

true

boolean

bufferWrites (common)

Deprecated Enable/Disable the buffering of HL7 payloads before writing to the socket.

false

boolean

hl7Headers (common)

Enable/Disable the automatic generation of message headers from the HL7 Message MLLP Consumers only

true

boolean

requireEndOfData (common)

Enable/Disable strict compliance to the MLLP standard. The MLLP standard specifies START_OF_BLOCKhl7 payloadEND_OF_BLOCKEND_OF_DATA, however, some systems do not send the final END_OF_DATA byte. This setting controls whether or not the final END_OF_DATA byte is required or optional.

true

boolean

stringPayload (common)

Enable/Disable converting the payload to a String. If enabled, HL7 Payloads received from external systems will be validated converted to a String. If the charsetName property is set, that character set will be used for the conversion. If the charsetName property is not set, the value of MSH-18 will be used to determine th appropriate character set. If MSH-18 is not set, then the default ISO-8859-1 character set will be use.

true

boolean

validatePayload (common)

Enable/Disable the validation of HL7 Payloads If enabled, HL7 Payloads received from external systems will be validated (see Hl7Util.generateInvalidPayloadExceptionMessage for details on the validation). If and invalid payload is detected, a MllpInvalidMessageException (for consumers) or a MllpInvalidAcknowledgementException will be thrown.

false

boolean

bridgeErrorHandler (consumer)

Allows for bridging the consumer to the Camel routing Error Handler, which mean any exceptions occurred while the consumer is trying to receive incoming messages, or the likes, will now be processed as a message and handled by the routing Error Handler. If disabled, the consumer will use the org.apache.camel.spi.ExceptionHandler to deal with exceptions by logging them at WARN or ERROR level and ignored.

true

boolean

exceptionHandler (consumer)

To let the consumer use a custom ExceptionHandler. Notice if the option bridgeErrorHandler is enabled then this option is not in use. By default the consumer will deal with exceptions, that will be logged at WARN or ERROR level and ignored.

ExceptionHandler

exchangePattern (consumer)

Sets the exchange pattern when the consumer creates an exchange. There are 3 enums and the value can be one of: InOnly, InOut, InOptionalOut

InOut

ExchangePattern

lazyStartProducer (producer)

Whether the producer should be started lazy (on the first message). By starting lazy you can use this to allow CamelContext and routes to startup in situations where a producer may otherwise fail during starting and cause the route to fail being started. By deferring this startup to be lazy then the startup failure can be handled during routing messages via Camel’s routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing.

false

boolean

basicPropertyBinding (advanced)

Whether the endpoint should use basic property binding (Camel 2.x) or the newer property binding with additional capabilities

false

boolean

synchronous (advanced)

Sets whether synchronous processing should be strictly used (this component only supports synchronous operations).

true

boolean

charsetName (codec)

Set the CamelCharsetName property on the exchange

String

backlog (tcp)

The maximum queue length for incoming connection indications (a request to connect) is set to the backlog parameter. If a connection indication arrives when the queue is full, the connection is refused.

5

Integer

keepAlive (tcp)

Enable/disable the SO_KEEPALIVE socket option.

true

Boolean

lenientBind (tcp)

TCP Server Only - Allow the endpoint to start before the TCP ServerSocket is bound. In some environments, it may be desirable to allow the endpoint to start before the TCP ServerSocket is bound.

false

boolean

maxConcurrentConsumers (tcp)

The maximum number of concurrent MLLP Consumer connections that will be allowed. If a new connection is received and the maximum is number are already established, the new connection will be reset immediately.

5

int

receiveBufferSize (tcp)

Sets the SO_RCVBUF option to the specified value (in bytes)

8192

Integer

reuseAddress (tcp)

Enable/disable the SO_REUSEADDR socket option.

false

Boolean

sendBufferSize (tcp)

Sets the SO_SNDBUF option to the specified value (in bytes)

8192

Integer

tcpNoDelay (tcp)

Enable/disable the TCP_NODELAY socket option.

true

Boolean

acceptTimeout (timeout)

Timeout (in milliseconds) while waiting for a TCP connection TCP Server Only

60000

int

bindRetryInterval (timeout)

TCP Server Only - The number of milliseconds to wait between bind attempts

5000

int

bindTimeout (timeout)

TCP Server Only - The number of milliseconds to retry binding to a server port

30000

int

connectTimeout (timeout)

Timeout (in milliseconds) for establishing for a TCP connection TCP Client only

30000

int

idleTimeout (timeout)

The approximate idle time allowed before the Client TCP Connection will be reset. A null value or a value less than or equal to zero will disable the idle timeout.

Integer

maxReceiveTimeouts (timeout)

Deprecated The maximum number of timeouts (specified by receiveTimeout) allowed before the TCP Connection will be reset.

Integer

readTimeout (timeout)

The SO_TIMEOUT value (in milliseconds) used after the start of an MLLP frame has been received

5000

int

receiveTimeout (timeout)

The SO_TIMEOUT value (in milliseconds) used when waiting for the start of an MLLP frame

15000

int

MLLP Consumer

The MLLP Consumer supports receiving MLLP-framed messages and sending HL7 Acknowledgements. The MLLP Consumer can automatically generate the HL7 Acknowledgement (HL7 Application Acknowledgements only - AA, AE and AR), or the acknowledgement can be specified using the CamelMllpAcknowledgement exchange property. Additionally, the type of acknowledgement that will be generated can be controlled by setting the CamelMllpAcknowledgementType exchange property.

Message Headers

The MLLP Consumer adds these headers on the Camel message:

Key

Description

CamelMllpLocalAddress

The local TCP Address of the Socket

CamelMllpRemoteAddress

The local TCP Address of the Socket

CamelMllpSendingApplication

MSH-3 value

CamelMllpSendingFacility

MSH-4 value

CamelMllpReceivingApplication

MSH-5 value

CamelMllpReceivingFacility

MSH-6 value

CamelMllpTimestamp

MSH-7 value

CamelMllpSecurity

MSH-8 value

CamelMllpMessageType

MSH-9 value

CamelMllpEventType

MSH-9-1 value

CamelMllpTriggerEvent

MSH-9-2 value

CamelMllpMessageControlId

MSH-10 value

CamelMllpProcessingId

MSH-11 value

CamelMllpVersionId

MSH-12 value

CamelMllpCharset

MSH-18 value

All headers are String types. If a header value is missing, its value is null.

Exchange Properties

The type of acknowledgment the MLLP Consumer generates and state of the TCP Socket can be controlled by these properties on the Camel exchange:

Key

Type

Description

CamelMllpAcknowledgement

byte[]

If present, this property will we sent to client as the MLLP Acknowledgement

CamelMllpAcknowledgementString

String

If present and CamelMllpAcknowledgement is not present, this property will we sent to client as the MLLP Acknowledgement

CamelMllpAcknowledgementMsaText

String

If neither CamelMllpAcknowledgement or CamelMllpAcknowledgementString are present and autoAck is true, this property can be used to specify the contents of MSA-3 in the generated HL7 acknowledgement

CamelMllpAcknowledgementType

String

If neither CamelMllpAcknowledgement or CamelMllpAcknowledgementString are present and autoAck is true, this property can be used to specify the HL7 acknowledgement type (i.e. AA, AE, AR)

CamelMllpAutoAcknowledge

Boolean

Overrides the autoAck query parameter

CamelMllpCloseConnectionBeforeSend

Boolean

If true, the Socket will be closed before sending data

CamelMllpResetConnectionBeforeSend

Boolean

If true, the Socket will be reset before sending data

CamelMllpCloseConnectionAfterSend

Boolean

If true, the Socket will be closed immediately after sending data

CamelMllpResetConnectionAfterSend

Boolean

If true, the Socket will be reset immediately after sending any data

MLLP Producer

The MLLP Producer supports sending MLLP-framed messages and receiving HL7 Acknowledgements. The MLLP Producer interrogates the HL7 Acknowledgments and raises exceptions if a negative acknowledgement is received. The received acknowledgement is interrogated and an exception is raised in the event of a negative acknowledgement.

Message Headers

The MLLP Producer adds these headers on the Camel message:

Key

Description

CamelMllpLocalAddress

The local TCP Address of the Socket

CamelMllpRemoteAddress

The remote TCP Address of the Socket

CamelMllpAcknowledgement

The HL7 Acknowledgment byte[] received

CamelMllpAcknowledgementString

The HL7 Acknowledgment received, converted to a String

Exchange Properties

The state of the TCP Socket can be controlled by these properties on the Camel exchange:

Key

Type

Description

CamelMllpCloseConnectionBeforeSend

Boolean

If true, the Socket will be closed before sending data

CamelMllpResetConnectionBeforeSend

Boolean

If true, the Socket will be reset before sending data

CamelMllpCloseConnectionAfterSend

Boolean

If true, the Socket will be closed immediately after sending data

CamelMllpResetConnectionAfterSend

Boolean

If true, the Socket will be reset immediately after sending any data

Spring Boot Auto-Configuration

When using mllp with Spring Boot make sure to use the following Maven dependency to have support for auto configuration:

<dependency>
  <groupId>org.apache.camel.springboot</groupId>
  <artifactId>camel-mllp-starter</artifactId>
  <version>x.x.x</version>
  <!-- use the same version as your Camel core version -->
</dependency>

The component supports 7 options, which are listed below.

Name Description Default Type

camel.component.mllp.autowired-enabled

Whether autowiring is enabled. This is used for automatic autowiring options (the option must be marked as autowired) by looking up in the registry to find if there is a single instance of matching type, which then gets configured on the component. This can be used for automatic configuring JDBC data sources, JMS connection factories, AWS Clients, etc.

true

Boolean

camel.component.mllp.bridge-error-handler

Allows for bridging the consumer to the Camel routing Error Handler, which mean any exceptions occurred while the consumer is trying to pickup incoming messages, or the likes, will now be processed as a message and handled by the routing Error Handler. By default the consumer will use the org.apache.camel.spi.ExceptionHandler to deal with exceptions, that will be logged at WARN or ERROR level and ignored.

false

Boolean

camel.component.mllp.default-charset

Set the default character set to use for byte to/from String conversions. The option is a java.nio.charset.Charset type.

Charset

camel.component.mllp.enabled

Whether to enable auto configuration of the mllp component. This is enabled by default.

Boolean

camel.component.mllp.lazy-start-producer

Whether the producer should be started lazy (on the first message). By starting lazy you can use this to allow CamelContext and routes to startup in situations where a producer may otherwise fail during starting and cause the route to fail being started. By deferring this startup to be lazy then the startup failure can be handled during routing messages via Camel’s routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing.

false

Boolean

camel.component.mllp.log-phi

Set the component to log PHI data.

true

Boolean

camel.component.mllp.log-phi-max-bytes

Set the maximum number of bytes of PHI that will be logged in a log entry.

5120

Integer