Crate ringlog

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This crate provides an asynchronous logging backend that can direct logs to one or more outputs.

The core of this crate is the RingLog type, which is constructed using a builder that is specific to your logging needs. After building the RingLog, it can be registered as the global logger using the start method. You will be left with a Box<dyn Drain> which should be periodically flushed outside of any critical path. For example, in an admin thread or dedicated logging thread.

For logging to a single file, the LogBuilder type can be used to construct an RingLog which has low overhead, but directs log messages to a single Output.

A SamplingLogBuilder can be used to construct an RingLog which will filter the log messages using sampling before directing the log messages to a single Output.

A MultiLogBuilder can be used to construct an RingLog which routes log messages based on the target metadata of the log Record. If there is an RingLog registered for that specific target, then the log message will be routed to that instance of RingLog. Log messages that do not match any specific target will be routed to the default RingLog that has been added to the MultiLogBuilder. If there is no default, messages that do not match any specific target will be simply dropped.

This combination of logging types allows us to compose a logging backend which meets the application’s needs. For example, you can use a local log macro to set the target to some specific category and log those messages to a file, while letting all other log messages pass to standard out. This could allow splitting command/access/audit logs from the normal logging.

Macros

  • debug
    Logs a message at the debug level.
  • error
    Logs a message at the error level.
  • fatal
  • info
    Logs a message at the info level.
  • log
    The standard logging macro.
  • log_enabled
    Determines if a message logged at the specified level in that module will be logged.
  • trace
    Logs a message at the trace level.
  • warn
    Logs a message at the warn level.

Structs

  • File
    A file based output which allows rotating the current log file off to a backup location.
  • LogBuilder
    A type to construct a basic RingLog which routes all log messages to a single Output.
  • Metadata
    Metadata about a log message.
  • MetadataBuilder
    Builder for Metadata.
  • MultiLogBuilder
    A type to construct a multi-target RingLog which routes messages based on the log’s target metadata to a corresponding RingLog. Targets which do not match a specific target will be routed to the default RingLog if one is configured.
  • NopLogBuilder
    A type to construct a basic RingLog which drops all log messages.
  • ParseLevelError
    The type returned by from_str when the string doesn’t match any of the log levels.
  • Record
    The “payload” of a log message.
  • RecordBuilder
    Builder for Record.
  • RingLog
    A type which implements an asynchronous logging backend.
  • SamplingLogBuilder
    A type to construct a basic RingLog which routes 1 in N log messages to a single Output.
  • SetLoggerError
    The type returned by set_logger if set_logger has already been called.
  • Stderr
    An output that writes to stderr.
  • Stdout
    An output that writes to stdout.

Enums

  • Level
    An enum representing the available verbosity levels of the logger.
  • LevelFilter
    An enum representing the available verbosity level filters of the logger.

Constants

Statics

Traits

  • Drain
    A Drain serves to receive log messages from a queue and flush them to an Output.
  • Log
    A trait encapsulating the operations required of a logger.
  • Output
    An Output is a logging destination, for example, standard out or a file.

Functions

Type Aliases