log

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Module

The log accessor is exported by the urn:org:ten60:netkernel:ext:sys module. Import this module to gain access to the accessor.

Syntax

URI

active:log

Argument	Rules	Description
operand	Mandatory	the resource to be serialized to the log
operator	Optional	optional configuration document

Example Usage

DPML

<instr>
  <type>log</type>
  <operand>foo.xml</operand>
  <operator>
    <log>
      <string />
      <request />
      <warning />
    </log>
  </operator>
</instr>

NetKernel Foundation API

req=context.createSubRequest("active:log");
req.addArgument("operand", [resource representation, aspect, or URI] );
result=context.issueSubRequest(req);

Purpose

The log accessor appends a record to the system log. It is useful for debuging, for critical failure reports, or for status messages.

The log accessor serializes the operand resource to the system log. Log entries default to the application level and can be optionally set to info, warning, or severe.

System loggers are configured by the administrator. Also see application-log which is used to write to application specific log files.

Operator Syntax

The log accessor takes an optional operator.

If the /log/string element exists then the operand is assumed to be XML and the text of the root element is serialized. If it doesn't exist or there is no operator then the whole operand is serialized to the log.

If the /log/request element exists then the parent request that initiated the log request is prepended as the first line of this log entry.

An optional info, warning, or severe element sets the logging severity. By default the logging level is application.

Example

Write a Message to the Log

<instr>
  <type>log</type>
  <operand>
    <message>Entering critical processing section</message>
  </operand>
  <operator>
    <log>
      <string />
    </log>
  </operator>
</instr>

An example of writing a message to the log