*force*

Overrides the default rules for choosing between logging directly or via an
agent. Defaults to nil. See log* for details.

*logger-factory*

An instance satisfying the impl/LoggerFactory protocol. Used internally to
obtain an impl/Logger. Defaults to the value returned from impl/find-factory.

*logging-agent*

The default agent used for performing logging when direct logging is
disabled. See log* for details.

*tx-agent-levels*

The set of levels that will require using an agent when logging from within a
running transaction. Defaults to #{:info :warn}. See log* for details.

debug

Usage: (debug message & more)
       (debug throwable message & more)

Debug level logging using print-style args.

debugf

Usage: (debugf fmt & fmt-args)
       (debugf throwable fmt & fmt-args)

Debug level logging using format.

enabled?

Usage: (enabled? level)
       (enabled? level logger-ns)

Returns true if the specific logging level is enabled.  Use of this macro
should only be necessary if one needs to execute alternate code paths beyond
whether the log should be written to.

error

Usage: (error message & more)
       (error throwable message & more)

Error level logging using print-style args.

errorf

Usage: (errorf fmt & fmt-args)
       (errorf throwable fmt & fmt-args)

Error level logging using format.

fatal

Usage: (fatal message & more)
       (fatal throwable message & more)

Fatal level logging using print-style args.

fatalf

Usage: (fatalf fmt & fmt-args)
       (fatalf throwable fmt & fmt-args)

Fatal level logging using format.

info

Usage: (info message & more)
       (info throwable message & more)

Info level logging using print-style args.

infof

Usage: (infof fmt & fmt-args)
       (infof throwable fmt & fmt-args)

Info level logging using format.

log

Usage: (log level message)
       (log level throwable message)
       (log logger-ns level throwable message)
       (log logger-factory logger-ns level throwable message)

Evaluates and logs a message only if the specified level is enabled. See log*
for more details.

log*

Usage: (log* logger level throwable message)

Attempts to log a message, either directly or via an agent; does not check if
the level is enabled.

For performance reasons, an agent will only be used when invoked within a
running transaction, and only for logging levels specified by
*tx-agent-levels*. This allows those entries to only be written once the
transaction commits, and are discarded if it is retried or aborted.  As
corollary, other levels (e.g., :debug, :error) will be written even from
failed transactions though at the cost of repeat messages during retries.

One can override the above by setting *force* to :direct or :agent; all
subsequent writes will be direct or via an agent, respectively.

log-capture!

Usage: (log-capture! logger-ns)
       (log-capture! logger-ns out-level err-level)

Captures System.out and System.err, piping all writes of those streams to
the log. If unspecified, levels default to :info and :error, respectively.
The specified logger-ns value will be used to namespace all log entries.

Note: use with-logs to redirect output of *out* or *err*.

Warning: if the logging implementation is configured to output to System.out
(as is the default with java.util.logging) then using this function will
result in StackOverflowException when writing to the log.

log-stream

Usage: (log-stream level logger-ns)

Creates a PrintStream that will output to the log at the specified level.

log-uncapture!

Usage: (log-uncapture!)

Restores System.out and System.err to their original values.

logf

Usage: (logf level fmt & fmt-args)
       (logf level throwable fmt & fmt-args)

Logs a message using a format string and args. Can optionally take a
throwable as its second arg. See level-specific macros, e.g., debugf.

logp

Usage: (logp level message & more)
       (logp level throwable message & more)

Logs a message using print style args. Can optionally take a throwable as its
second arg. See level-specific macros, e.g., debug.

spy

Usage: (spy expr)
       (spy level expr)

Evaluates expr and may write the form and its result to the log. Returns the
result of expr. Defaults to :debug log level.

trace

Usage: (trace message & more)
       (trace throwable message & more)

Trace level logging using print-style args.

tracef

Usage: (tracef fmt & fmt-args)
       (tracef throwable fmt & fmt-args)

Trace level logging using format.

warn

Usage: (warn message & more)
       (warn throwable message & more)

Warn level logging using print-style args.

warnf

Usage: (warnf fmt & fmt-args)
       (warnf throwable fmt & fmt-args)

Warn level logging using format.

with-logs

Usage: (with-logs logger-ns & body)
       (with-logs [logger-ns out-level err-level] & body)

Evaluates exprs in a context in which *out* and *err* write to the log. The
specified logger-ns value will be used to namespace all log entries.

By default *out* and *err* write to :info and :error, respectively.

Logger

The protocol through which the core api will interact with an underlying logging
implementation.  Implementations should at least support the six standard
logging levels if they wish to work from the level-specific macros.

Usage: (enabled? logger level)

Check if a particular level is enabled for the given Logger.

Usage: (write! logger level throwable message)

Writes a log message to the given Logger.

LoggerFactory

The protocol through which the core api will obtain an instance satisfying Logger
as well as providing information about the particular implementation being used.
Implementations should be bound to *logger-factory* in order to be picked up by
this library.

Usage: (get-logger factory logger-ns)

Returns an implementation-specific Logger by namespace.

Usage: (name factory)

Returns some text identifying the underlying implementation.

cl-factory

Usage: (cl-factory)

Returns a Commons Logging-based implementation of the LoggerFactory protocol, or
nil if not available.

find-factory

Usage: (find-factory)

Returns the first non-nil value from slf4j-factory, cl-factory,
log4j-factory, and jul-factory.

jul-factory

Usage: (jul-factory)

Returns a java.util.logging-based implementation of the LoggerFactory protocol,
or nil if not available.

log4j-factory

Usage: (log4j-factory)

Returns a Log4j-based implementation of the LoggerFactory protocol, or nil if
not available.

slf4j-factory

Usage: (slf4j-factory)

Returns a SLF4J-based implementation of the LoggerFactory protocol, or nil if
not available.