You can activate Node.js application tracing by turning on SJ component tracing. Small
amounts of trace are written to the internal trace table, but Node.js also writes out logging
information to a unique file in zFS for each Node.js application. This file does not wrap so you
must manage its size in zFS.
About this task
Node.js application tracing does not use auxiliary or GTF tracing. CICS® writes some information to the internal trace table. However, most
diagnostic information is logged by Node.js and written to a file in zFS. This file is uniquely
named for each Node.js application. The default file name has the format
&DATE;.&TIME;.trace and is created by CICS in the
$WORK_DIR/&APPLID;/&NODEJSAPP;
directory when you enable the NODEJSAPP resource. You can change the name and the location of this
trace file by using the TRACE profile option. Changes to the profile take affect
when the NODEJSAPP resource is enabled. If you delete or rename the trace file when the Node.js
application is running, CICS does not re-create the file and
the logging information is not written to another file.
Procedure
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Use the CETR transaction to activate tracing for the Node.js application. Select the SJ
component to trace the actions taken by CICS to start and
stop the Node.js application. Node.js logs diagnostic information in the zFS file.
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Set the tracing level for the SJ component:
- SJ level 0 produces tracing for exceptions only, such as errors during the initialization of
the Node.js application. SJ level 1 and level 2 produce more CICS tracing from the SJ domain. This tracing is written to the internal trace table.
- SJ level 3 produces additional logging from Node.js, such as warning and information
messages. This information is written to the trace file in zFS.
- SJ level 4, 5 produce debug information from CICS and
Node.js, which provides much more detailed information about the Node.js application processing.
This information is written to the trace file in zFS.
-
Each trace entry has a date and time stamp. You can change the name and the location of this
trace file by using the TRACE
profile option.
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If you are using the default TRACE settings, when you enable the NODEJSAPP
resource CICS creates a new unique trace file for the life of
the Node.js application.
If you disable the NODEJSAPP resource, you can delete the trace file or rename the file if you
want to retain the information separately.
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To manage the number of files, you can set the LOG_FILES_MAX option to control the number of old trace files that are
retained on the Node.js application startup.