Replikwando Error Logging

Contained within this page are the inner workings of Replikwando's logging system as of version 1.7.0.

Log Levels

This setting determines what severity of issue is logged. Each level includes all the ones of higher priority as well.

Values

This value can be set in replication.ini, logging::loglevel.

Only one value is accepted, in the form of:

• loglevel=<log_level_value>

Acceptable values are (in order of criticality):

• CRITICAL
• ERROR
• WARNING
• GENERAL
• NOTIFY
• DEBUG

Critical

Notifies the user that there are issues that require immediate attention (whether by user or programmer), and that Replikwando cannot function normally until they are corrected.

Examples:

• Basic configuration is not set
• Could not connect to local or remote database on startup
• Binary logging is not enabled
• Could not create or open sqlite file
• Processing threads have died unexpectedly (programmer must correct)
• CRT or other generic unhandled error or exception (programmer must handle)

Error

Notifies the user that issues are coming up that are stopping Replikwando from functioning correctly.

Examples:

• Loss of local or remote connection
• Inability to trigger a heartbeat

Warning

Notifies the user that some issues are coming up, but Replikwando is capable of getting along without intervention.

Examples:

• Any query that errors out for known reasons like DUPLICATE KEY or ALREADY_EXISTS

General

Details important state changes (like repushing) and other things that are nice to know, but won't require action by the users.

Examples:

• Repush started
• Repush finished

Notify

Details general state changes and higher-level debugging information.

Examples:

• Heartbeat message received
• Discarded known duplicate query (ROLLBACK; ROLLBACK;)
• Function creation without determinism set
• Short-form queries being added to sqlite file

Debug

Contains tons of otherwise-useless output; queries being written out and such.

Not good for general use.

Examples:

• First 2KB of each query being sent to remote server.

Log Types

This setting determines what sources of message are considered for logging. It is completely agnostic of severity.

Values

This value can be set in replication.ini, logging::log_types.

Multiple values may be specified on this line, in the form of

• log_types=<log_type_value>[ log_type_value...]

Acceptable values are:

• GENERAL
• STARTUP
• SHUTDOWN
• PERFORMANCE

• THREAD_MAIN
• THREAD_READ
• THREAD_PARSE
• THREAD_STORE
• THREAD_SEND
• THREAD_HEARTBEAT

• EXTRA_DATA_SQLITE_CHANGE
• TEST_SUITE

General

Catch-all category for anything that comes from non-specific locations. It should probably always be enabled.

Startup

Issues that occur while Replikwando is starting up and putting itself into a normal running state.

Shutdown

Issues that occur while Replikwando is closing down and cleaning up values.

Performance

Logged values related to performance, such as query lengths and queue sizes.

Thread_Main

Issues that occur in the main thread of Replikwando. The main thread doesn't do much, and most if not all values that go here would be better handled under General instead.

Thread_Read

Issues that occur during reading values from the local database.

Thread_Parse

Issues that occur during the parsing of unparsed queries. Involves tokenization and introspection of MySQL queries.

Thread_Store

Issues that occur during saving parsed queries to the SQLite database file.

Thread_Send

Issues that occur during sending values to any number of remote databases.

Thread_Heartbeat

Issues that occur during the triggering of heartbeats, or the reading and writing of Replikwando Messages.

Extra_data_SQLite_Change

Notifications for SQLite values being manipulated. Performance logging.

Test_Suite

Eventually will be used for parse-friendly output to enable testing. I hope.

Log Format

Currently, the log format is hard-coded to be:

• Locale_String_Date_Time [Log_Level : Log_Type] - Full_Message

Please note that Full_message may have any variety of formatting, including tabbing, unescaped raw ascii values, and line returns.

Known Errors

Please review this wiki page.