log connectionId

[Dmole]

Add connectionId to the access log options so the connectionId in the error log can be cross referenced to an IP for debug, fail2ban, etc.

[markt-asf]

This is not the way to do this. Look at the ExtendedAccessLogValve. Look at x-H(...) options.

[Dmole]

I added it to both AccessLogValve and ExtendedAccessLogValve because it is non-trivial for users to switch between them as the documentation does not provide a mapping (EG: %v = ?), and the extended valve does not permit arbitrary formatting (EG: JSON log).

is that OK?

[markt-asf]

That looks good for for the ExtendedAccessLogValve.

I don't like that this is automatically added as a request attribute. Firstly, if we add this field, why not all the others? Secondly, it seems wrong to add this as an attribute when there is a perfectly good API to obtain the ID. I think that means AccessLogValve needs something like x-H(XXX). The question is what to use since we try and keep this aligned with httpd and we don't know what they'll choose to do in the future. Maybe %{XXX}x?

[rainerjung]

Concerning analogies in Apache httpd land:

ErrorLogFormat has

%{c}L 	Log ID of the connection
%{C}L 	Log ID of the connection if used in connection scope, empty otherwise

and explains them as

The log ID format %L produces a unique id for a connection or request. This can be used to correlate which log lines belong to the same connection or request, which request happens on which connection. A %L format string is also available in [mod_log_config](https://httpd.apache.org/docs/2.4/en/mod/mod_log_config.html) to allow to correlate access log entries with error log lines. If [mod_unique_id](https://httpd.apache.org/docs/2.4/en/mod/mod_unique_id.html) is loaded, its unique id will be used as log ID for requests.

See: https://httpd.apache.org/docs/2.4/en/mod/core.html#errorlogformat

And as mentioned here, mod_log_config documents:
%L The request log ID from the error log (or '-' if nothing has been logged to the error log for this request). Look for the matching error log line to see what request caused what error.

I haven't checked what the connection id in Tomcat land is and how well this analogy applies.

Furthermore mod_https provides some IDs via httpd env vars (%{...}e):

Variable Name: 	Value Type: 	Description:
HTTP2	flag	HTTP/2 is being used.
H2PUSH	flag	HTTP/2 Server Push is enabled for this connection and also supported by the client.
H2_PUSH	flag	alternate name for H2PUSH
H2_PUSHED	string	empty or PUSHED for a request being pushed by the server.
H2_PUSHED_ON	number	HTTP/2 stream number that triggered the push of this request.
H2_STREAM_ID	number	HTTP/2 stream number of this request.
H2_STREAM_TAG	string	HTTP/2 process unique stream identifier, consisting of connection id and stream id separated by 

[Dmole]

Added %{c}L and x-H(connectionId) to AccessLogValve and ExtendedAccessLogValve to cross reference errors from catalina.log

[markt-asf]

Manually applied as there were a few things I needed to add/change

• %{xxx}L is for ID attributes not connection attributes
• new settings needed to be added to the docs
• change log entry was required
• The CachedElement interface does not apply here

[Dmole]

3cfc9bc

987f737