ResetContentDescriptor node
Use the ResetContentDescriptor node to request that the message is reparsed by a different parser.
- Developer
- Application Integration Suite
- Standard
- Advanced
- Express
- Scale
This topic contains the following sections:
Purpose
The node associates the new parser information with the input message bit stream. If the message has been parsed already to create a message tree, and the contents of the tree have been modified (for example, by a Compute node), the ResetContentDescriptor node must re-create the bit stream from the message tree by calling the current parser.
If your message flow has updated the message before it is received by the ResetContentDescriptor node, ensure that the changed message contents are still valid for the current parser. If the contents are not valid, the parser generates an error when it attempts to re-create the bit stream from the message tree, and the ResetContentDescriptor node raises an exception. For example, if you have added a new field to a message in the MRM domain, and the field is not present in the model, the recreation of the bit stream fails.
If you specify MRM as the new parser, you can also specify a different message template (message set, message type, and message format). If you specify DFDL as the new parser, you can also specify a different Schema Location and Document Root. This node does not reparse the message, but the properties that you set for this node determine how the message is parsed when it is next reparsed by the message flow.
The ResetContentDescriptor node does not:
- Change the message content; it changes message properties to specify how the bit stream is parsed next time that the parser is started.
- Convert the message from one format to another; for example, if the incoming message has a message format of XML and the outgoing message format is binary, the ResetContentDescriptor node does not do any reformatting. It starts the parser to re-create the bit stream of the incoming XML message, which retains the XML tags in the message. When the message is reparsed by a subsequent node, the XML tags are not valid and the parse fails.
The ResetContentDescriptor node is contained in the Construction drawer of the palette, and is represented in the IBM® Integration Toolkit by the following icon:
Using this node in a message flow
For an example of how to use this node, assume that you want to swap between the BLOB and the MRM domains. The format of an incoming message might be unknown when it enters a message flow, therefore the BLOB parser is started. Later on in the message flow, you might decide that the message is predefined as a message in the MRM domain, and you can use the ResetContentDescriptor node to set the correct values to use when the message is parsed by a subsequent node in the message flow.
| Property | Value |
|---|---|
| Message domain | DFDL |
| Reset message domain | Selected |
| Message model | MyMessageModel |
| Reset message model | Selected |
| Message | m_MESSAGE1 |
| Reset message | Selected |
| Physical format | |
| Reset phsyical format | Selected |
The Message domain is set to DFDL, and the DFDL parser is started when the message is next parsed. The Message model and Message are the message template values that define the message model, and all of the reset check boxes are selected because all of the properties need to change. The value of the Message model property is supplied for you.
The ResetContentDescriptor node causes the BLOB parser that is associated with the input message to construct the physical bit stream of the message (not the logical tree representation of it), which is later passed to the MRM parser. The MRM parser then parses the bit stream using the message template (Message set, Message type, and Message format) specified in this ResetContentDescriptor node.
Terminals and properties
The ResetContentDescriptor node terminals are described in the following table.
| Terminal | Description |
|---|---|
| In | The input terminal that accepts a message for processing by the node. |
| Failure | The output terminal to which the message is routed if an error is detected by the node. |
| Out | The output terminal to which the message is routed if a new parser is identified by the properties. |
The following tables describe the node properties. The column headed M indicates whether the property is mandatory (marked with an asterisk if you must enter a value when no default is defined); the column headed C indicates whether the property is configurable (you can change the value when you add the message flow to the BAR file to deploy it).
The Description properties of the ResetContentDescriptor node are described in the following table.
| Property | M | C | Default | Description |
|---|---|---|---|---|
| Node name | No | No | The node type | The name of the node. |
| Short description | No | No | A brief description of the node. | |
| Long description | No | No | Text that describes the purpose of the node in the message flow. |
The Basic properties of the ResetContentDescriptor node are described in the following table.
The ResetContentDescriptor node Basic properties are described in the following table.
| Property | M | C | Default | Description |
|---|---|---|---|---|
| Message domain | No | No | BLOB | The message domain that is associated with the message that you want to reparse. |
| Reset message domain | Yes | No | Cleared | If you select the reset check box, the Message domain property is reset. In this case, if you do not select a value for the Message domain property, the Message domain property value is BLOB. |
| Message model | No | No | The name or location of the message model schema file in which the message that you want to reparse is defined. When you click Browse, you see a list of available message model schema files for the selected domain. | |
| Reset message model | Yes | No | Cleared | If you select the reset check box, the Schema Location property is reset. In this case, if you do not select a value for the Schema Location property, the Schema Location property value is blank. |
| Message | No | No | The name or location of a global element that models an entire document of data, and is contained in your message model schema file. This list is populated with all available messages that are defined in the Message model that you have selected. | |
| Reset message | Yes | No | Cleared | If you select the reset check box, the Document Root property is reset. In this case, if you do not select a value for the Document Root property, the Document Root property value is blank. |
| Physical Format | No | No | It is not necessary to select the physical format of the message you want to reparse if you are using the DFDL domain. The physical format of your message is defined in the DFDL schema file that you have selected. | |
| Reset physical format | Yes | No | Cleared | If you select the reset check box, the Physical Format property is reset. In this case, if you do not select a value for the Physical Format property, the Physical Format property value is blank. |
The Parser Options properties of the ResetContentDescriptor node are described in the following table.
| Property | M | C | Default | Description |
|---|---|---|---|---|
| Parse timing | No | No | On Demand | This property controls when the reparsed message
is parsed. Valid values are On
Demand, Immediate,
and Complete. For a full description of this property, see Parsing on demand. |
| Use MQRFH2C compact parser for MQRFH2 header | No | No | Cleared | This property controls whether the MQRFH2C compact parser, instead of the MQRFH2 parser, is used for MQRFH2 headers. |
| Build tree using XML schema data types | No | No | Cleared | This property controls whether the XMLNSC parser creates syntax elements in the message tree with data types taken from the XML Schema. You can select this property only if you set the Validate property on the Validation tab to Content or Content and Value. |
| Use XMLNSC compact parser for XMLNS domain | No | No | Cleared | This property controls whether the XMLNSC Compact Parser is used for messages in the XMLNS Domain. If you set this property, the message data is displayed under XMLNSC in nodes that are connected to the output terminal when the input MQRFH2 header or Domain is XMLNS. |
| Retain mixed content | No | No | Cleared | This property controls whether the XMLNSC parser creates elements in the message tree when it encounters mixed text in the reparsed message. If you select the check box, elements are created for mixed text. If you clear the check box, mixed text is ignored and no elements are created. |
| Retain comments | No | No | Cleared | This property controls whether the XMLNSC parser creates elements in the message tree when it encounters comments in the reparsed message. If you select the check box, elements are created for comments. If you clear the check box, comments are ignored and no elements are created. |
| Retain processing instructions | No | No | Cleared | This property controls whether the XMLNSC parser creates elements in the message tree when it encounters processing instructions in the reparsed message. If you select the check box, elements are created for processing instructions. If you clear the check box, processing instructions are ignored and no elements are created. |
| Opaque elements | No | No | Blank | This property is used to specify a list of elements in the reparsed message that are to be opaquely parsed by the XMLNSC parser. Opaque parsing is performed only if validation is not enabled (that is, if the value of the Validate property is set to None); entries that are specified in Opaque Elements are ignored if validation is enabled. |
The Validation properties of the ResetContentDescriptor node are described in the following table. For a full description of these properties, see Validation properties.
| Property | M | C | Default | Description | mqsiapplybaroverride command property |
|---|---|---|---|---|---|
| Validate | No | Yes | None | This property controls whether validation takes place. Valid values are None, Content, Content and Value, and Inherit. | validateMaster |
| Failure action | No | No | Exception | This property controls what happens if validation fails. You can set this property only if you set Validate to Content and Value or Content. Valid values are User Trace, Local Error Log, Exception, and Exception List. |
| Property | M | C | Default | Description |
|---|---|---|---|---|
| Events | No | No | None | Events that you have defined for the node are
displayed on this tab. By default, no monitoring events are defined
on any node in a message flow. Use Add, Edit,
and Delete to create, change or delete monitoring
events for the node; see Configuring monitoring event sources by using monitoring properties for details. You can enable and disable events that are shown here by selecting or clearing the Enabled check box. |