Connection activity logging only records the connection timestamp (E)

[wildtayne]

The Postgres connection logs record additional information ClassDB does not user, namely connection_from and application_name. It would be useful to record these attributes in the connection activity log.

[smurthys]

Adding this comment to make it visible. I recommend using this issue to capture the need to add host, application, and other information discussed in this morning's meeting.

I am adding this to the M3 list so it gets attention. We can remove it from the M3 pipeline if a discussion recommends so.

[wildtayne]

Adding a few comments based on yesterday's discussion:

• Setting log_destination to csvlog standardizes the log line format to match the format described in section 19.8.4, regardless of other settings like log_line_prefix. Other settings can effect when new lines are written, but not their structure.
• application_name is not actually a server parameter, rather, it is a environment variable set by the client. Confusingly, despite its inclusion in the logging docs, there is no server parameter to enable or disable logging application_name.
• According to the linked docs, application_name is recorded using csvlog, however an initial test on my system shows only a blank string logged as application name (despite SHOW application_name returning psql). However, manually setting application_name does cause the new value to be logged for the duration of the session. This will require further testing.

[afig]

Just wanted to add that my installation seems to log application_name for errors without needing to be manually set, but not for connection activity. The docs linked in the previous comment state:

The application_name can be any string of less than NAMEDATALEN characters (64 characters in a standard build). It is typically set by an application upon connection to the server

Could it be that application_name is simply not known by the server until some point after a connection is logged? Maybe it is logged on disconnect entries?

[smurthys]

Both the -d command-line option to psql and the \c meta-command allows setting application name using a "connection URI".

Any application creating a connection can set the application name via connection info. I expect app name to then show up in the corresponding connection entry in the server log.