Dequeue

Description


Allows you to perform a read from a queue or a topic (defined in section systems). Using the right mouse button you can edit/add operations or InputServices OutputServices.

Developer Studio (VulCon)/GV Console configuration


Operation node GVCore element Description
Enqueue GVOperationNode Allows to perform a communication with an external systems (invocation, sending messages, receiving messages).
Its op-type parameter will be setted to enqueue.

A GVOperationNode is an operation node indicating that GreenVulcano® ESB must perform a communication with an external systems (invocation, sending messages, receiving messages).
For example, if the node indicates a receive a message (see attribute op-type), you can also define a DequeueFilter that sets certain conditions that the received message must meet.

The GVOperationNode is a Flow element that extends FlowNode. It has the following attributes:

Attribute Type Description
class fixed This attributes must assume the value it.greenvulcano.gvesb.core.flow.GVOperationNode.
op-type fixed This attributes must assume the value call, enqueue, dequeue
id-system -dp required Identifies the system involved in communication. Can be selected from systems declared as Participant in the Operation section. The attribute value can't be null.
operation-name required Identifies the communication operation selected by the channel of the system indicated by the id-system attribute.
Only the operations of the type declared in the 'op-type' attribute can be selected.
Its value cannot be null.

and the subelements:

  • InputServices
  • OutputServices
  • DequeueFilter

InputServices


Before doing any communication you can run an ordered list of input services.
This section allows the definition of output services for the current communication operation. The current version of GreenVulcano® ESB provides the following services:

  • Data Transformation
  • XML Validation
  • OGNL/Java Scripting

The InputServices Element is used by: GVIteratorOperationNode and GVOperationNode.
Might contain the following elements:

  • Description
  • gvdte-service
  • xml-validation-service
  • ognl-script-service
  • java-script-service
  • dh-selector-service

OutputServices


After doing any communication you can run an ordered list of output services.
This section allows the definition of output services for the current communication operation.
The current version of GreenVulcano® ESB provides the following services:

  • Data Transformation
  • XML Validation
  • OGNL/Java Scripting

The OutputServices Element is used by ChangeGVBufferNode, GVIteratorOperationNode and GVOperationNode.

Might contain the following elements:

  • Description
  • gvdte-service
  • xml-validation-service
  • ognl-script-service
  • java-script-service

In/Out Services


gvdte-service


Invokes the Data Transformation Engine (GVDTE). Refer to the documentation GVDTE for information on features of GreenVulcano® ESB Data Transformation Engine.
The following table shows the gvdte-service element’s attributes:

Attribute Type Description
type fixed This attribute must assume the value service.
internal fixed This attribute must assume the value yes.
critical optional Defines if the service is critical. A critical service failure mark the entire communication as failed.
The attribute's default value is: yes.
remove-fields optional Indicates whether or not to remove from the buffer the fields used for communication with GVDTE. The attribute's default value is: yes.

Its sub-elements are:

  • Description
  • map-name-param
  • gvdte-context-call
  • gvdte-extra-param

map-name-param

Specifies the name of the transformation that should apply by GVDTE.
This name must indicate a transformation currently configured in GVDTE.
This parameter can be optional if the input GVBuffer has a property with the name map-name.

The following table shows the map-name-param element’s attributes:

Attribute Type Description
type fixed This attribute must assume the value param.
name fixed This attribute must assume the value map-name.
value required Specifies the name of the transformation that should apply by GVDTE.
This name must indicate a transformation currently configured in GVDTE.

gvdte-context-call

Communication parameters to interact with GVDTE.
The following table shows the gvdte-context-call element’s attributes:

Attribute Type Description
type fixed This attribute must assume the value call.
class fixed This attribute must assume the value it.greenvulcano.gvesb.virtual.internal.DTEServiceContextCall.
name required ID used for diagnostics. Is printed on the log files.

gvdte-extra-param

Allows you to specify additional parameters for the transformation GVDTE must apply.
The following table shows the gvdte-extra-param element’s attributes:

Attribute Type Description
type fixed This attribute must assume the value param.
name required Parameter name. The attribute's value can't be null.
value required Parameter value. The value of this attribute can be static or can be interpreted dynamically, as the value of a metadata expression that also employee the input GVBuffer.

xml-validation-service


Invokes the XML validation engine.
The following table shows the xml-validation-service element’s attributes:

Attribute Type Description
type fixed This attribute must assume the value service.
internal fixed This attribute must assume the value yes.

Its sub-elements are:

  • Description
  • xml-validation-call

xml-validation-call

Communication parameters to interact with XML validation engine.
The following table shows the xml-validation-call element’s attributes:

Attribute Type Description
type fixed This attribute must assume the value call.
class fixed This attribute must assume the value it.greenvulcano.gvesb.virtual.internal.xml.XMLValidationCallOperation.
name required ID used for diagnostics. Is printed on the log files.
The attribute's value can't be null.
default-xsd optional Policies for the use of default XSD.
If 'force-default' is always used the XSD specified in parameter 'default-xsd'.
If 'null xsd' is used used the XSD specified in parameter 'default-xsd' only if the schema specified in the XML is invalid.
Default 'force-default'
return-dom optional Returns the parsed and validated org.w3c.dom.Document corresponding to the input object.
The same object is returned if input already is a DOM Document. Default is 'false'.

Its sub-elements are:

  • Description
  • ServiceAlias

ognl-script-service


Internal service useful to execute OGNL scripts on GVBuffer instances.
The following table shows the ognl-script-service element’s attributes:

Attribute Type Description
type fixed This attribute must assume the value service.
internal fixed This attribute must assume the value yes.
critical optional Defines if the service is critical. A critical service failure mark the entire communication as failed.
The attribute's default value is: yes.

Its sub-elements are:

  • Description
  • ognl-script-call

ognl-script-call

VCL Operation useful to execute OGNL scripts on GVBuffer instances.
The following table shows the ognl-script-call element’s attributes:

Attribute Type Description
type fixed This attribute must assume the value call.
class fixed This attribute must assume the value it.greenvulcano.gvesb.virtual.internal.OGNLCallOperation.
name required Operation identifier. The attribute's value can't be null.

Its sub-elements are:

  • Description
  • OGNLScript

java-script-service


Internal service useful to execute JavaScript scripts on GVBuffer instances.
The following table shows the java-script-service element’s attributes:

Attribute Type Description
type fixed This attribute must assume the value service.
internal fixed This attribute must assume the value yes.
critical optional Defines if the service is critical. A critical service failure mark the entire communication as failed. The attribute's default value is: yes.

Its sub-elements are:

  • Description
  • java-script-call

java-script-call

VCL Operation useful to execute JavaScript scripts on GVBuffer instances.
The following table shows the java-script-call element’s attributes:

Attribute Type Description
type fixed This attribute must assume the value call.
class fixed This attribute must assume the value it.greenvulcano.gvesb.virtual.internal.JSCallOperation.
name required Operation identifier. The attribute's value can't be null.

Its sub-elements are:

  • Description
  • Script

dh-selector-service


Internal service useful to set DBOBuilder name to call at dh-call operations. Useful only as InputService of GVOperationNode that references a dh-call operation.
The following table shows the dh-selector-service element’s attributes:

Attribute Type Description
type fixed This attribute must assume the value service.
internal fixed This attribute must assume the value yes.
critical optional Defines if the service is critical. A critical service failure mark the entire communication as failed. The attribute's default value is: yes.

Its sub-elements are:

  • Description
  • dh-selector-call

dh-selector-call

VCL Operation useful to set DBOBuilder name to call contained in a dh-call operation.
The following table shows the dh-selector-call element’s attributes:

Attribute Type Description
type fixed This attribute must assume the value call.
class fixed This attribute must assume the value it.greenvulcano.gvesb.virtual.datahandler.DBOBuilderSelectorCallOperation.
name fixed Operation identifier. This attribute must assume the value setDBService.
DH_SERVICE_NAME required DBOBuilder name. The attribute's value can't be null.

Its sub-elements are:

  • Description

script-service


Internal service useful to execute scripts on GVBuffer instances. The following table shows the script-service element’s attributes:

Attribute Type Description
type fixed This attribute must assume the value services.
internal fixed This attribute must assume the value yes.
critical optional Defines if the service is critical. A critical service failure mark the entire communication as failed. The attribute's default value is: yes.

Its sub-elements are:

  • Description
  • script-call

script-call

VCL Operation useful to execute scripts on GVBuffer instances.
The following table shows the script-call element’s attributes:

Attribute Type Description
type fixed This attribute must assume the value call.
class fixed This attribute must assume the value
it.greenvulcano.gvesb.virtual.internal.ScriptCallOperation</b>.
name required Operation identifier. The attribute's value can't be null.

Its sub-elements are:

  • Description
  • Script

json-validation-service


Its sub-elements are:

  • Description
  • json-validation-call

json-validation-call

Its sub-elements are:

  • Description

Description

Each element of the configuration provides a field Description optional that might contain free text available to the user.

This field can be used for notes and information that help users in configuration management and by the application GV Console® to enrich the reports relating to the configuration.

The Description is always optional, but if used can not be empty. The element value cannot be null.