The log4r_step() function can be used as an action in the action_levels()
function (as a list component for the fns list). Place a call to this
function in every failure condition that should produce a log (i.e., warn,
stop, notify). Only the failure condition with the highest severity for a
given validation step will produce a log entry (skipping failure conditions
with lower severity) so long as the call to log4r_step() is present.
log4r_step(x, message = NULL, append_to = "pb_log_file")A reference to the x-list object prepared by the agent. This
version of the x-list is the same as that generated via
get_agent_x_list(<agent>, i = <step>) except this version is internally
generated and hence only available in an internal evaluation context.
The message to use for the log entry. When not provided, a
default glue string is used for the messaging. This is dynamic since the
internal glue::glue() call occurs in the same environment as x, the
x-list that's constrained to the validation step. The default message, used
when message = NULL is the glue string "Step {x$i} exceeded the {level} failure threshold (f_failed = {x$f_failed}) ['{x$type}']". As can be seen,
a custom message can be crafted that uses other elements of the x-list with
the {x$<component>} construction.
The file to which log entries at the warn level are appended. This can alternatively be one or more log4r appenders.
5-1