There are difficulties working with C++ Broker logging when appplying a log filter criterion. What precise FILTERTEXT can a user specify for:
Even after the fix from
QPID-3891 it is not intuitive what to specify for a FILTERTEXT and any useful filter requires detailed knowledge of the source code.
A log category is a high-level classification of the nature of the logged event that is not tied to a particular source module or code function name. This log category would become the target for FILTERTEXT log filters.
The following list is the proposed log category definition. Each log category name is followed by a list of source code directory names that would generally produce logs using that log category.
|Category||Source code directory|
|Security||acl ssl gssapi sasl cyrus|
|Management||agent console qmf|
|System||log sys types xml thread mutex fork pipe time ...|
|HA||cluster ha replication|
|IO||tcp rdma AsynchIO socket epoll|
There is no strict rule that a module produce only log entries of a specific category.
The category would be inserted into each log message after the time of day but before the message text.
A user could then filter log messages by using the category names:
This scheme would have a number of benefits:
1. On a per-message basis the filter comparisons would be using enumeration values and not strings.
2. The feature could be documented sensibly.
3. Log files would be easier to interpret manually or by event management systems.
The classifications could be phased in gradually. The current
QPID_LOG(LEVEL, MESSAGE) would produce [Unspecfied] events while the new
QPID_LOG_CAT(LEVEL, CATEGORY, MESSAGE) would produce events using an actual category.
Similar additions are made for the QPID_MSG entries.