Active Support Broadcast Logger
The Broadcast logger is a logger used to write messages to multiple IO
. It is commonly used in development to display messages on STDOUT and also write them to a file (development.log). With the Broadcast logger, you can broadcast your logs to a unlimited number of sinks.
The BroadcastLogger
acts as a standard logger and all methods you are used to are available. However, all the methods on this logger will propagate and be delegated to the other loggers that are part of the broadcast.
Broadcasting your logs.
stdout_logger = Logger.new(STDOUT)
file_logger = Logger.new("development.log")
broadcast = BroadcastLogger.new(stdout_logger, file_logger)
broadcast.info("Hello world!") # Writes the log to STDOUT and the development.log file.
Add a logger to the broadcast.
stdout_logger = Logger.new(STDOUT)
broadcast = BroadcastLogger.new(stdout_logger)
file_logger = Logger.new("development.log")
broadcast.broadcast_to(file_logger)
broadcast.info("Hello world!") # Writes the log to STDOUT and the development.log file.
Modifying the log level for all broadcasted loggers.
stdout_logger = Logger.new(STDOUT)
file_logger = Logger.new("development.log")
broadcast = BroadcastLogger.new(stdout_logger, file_logger)
broadcast.level = Logger::FATAL # Modify the log level for the whole broadcast.
Stop broadcasting log to a sink.
stdout_logger = Logger.new(STDOUT)
file_logger = Logger.new("development.log")
broadcast = BroadcastLogger.new(stdout_logger, file_logger)
broadcast.info("Hello world!") # Writes the log to STDOUT and the development.log file.
broadcast.stop_broadcasting_to(file_logger)
broadcast.info("Hello world!") # Writes the log *only* to STDOUT.
At least one sink has to be part of the broadcast. Otherwise, your logs will not be written anywhere. For instance:
broadcast = BroadcastLogger.new
broadcast.info("Hello world") # The log message will appear nowhere.
If you are adding a custom logger with custom methods to the broadcast, the ‘BroadcastLogger` will proxy them and return the raw value, or an array of raw values, depending on how many loggers in the broadcasts responded to the method:
class MyLogger < ::Logger
def loggable?
true
end
end
logger = BroadcastLogger.new
logger.loggable? # => A NoMethodError exception is raised because no loggers in the broadcasts could respond.
logger.broadcast_to(MyLogger.new(STDOUT))
logger.loggable? # => true
logger.broadcast_to(MyLogger.new(STDOUT))
puts logger.broadcasts # => [MyLogger, MyLogger]
logger.loggable? # [true, true]
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Attributes
[R] | broadcasts | Returns all the logger that are part of this broadcast. |
[R] | formatter | |
[RW] | progname |
Class Public methods
new(*loggers) Link
Instance Public methods
<<(message) Link
broadcast_to(*loggers) Link
Add logger(s) to the broadcast.
broadcast_logger = ActiveSupport::BroadcastLogger.new
broadcast_logger.broadcast_to(Logger.new(STDOUT), Logger.new(STDERR))
close() Link
debug(...) Link
debug!() Link
Sets the log level to Logger::DEBUG for the whole broadcast.
debug?() Link
True
if the log level allows entries with severity Logger::DEBUG to be written to at least one broadcast. False
otherwise.
error(...) Link
error!() Link
Sets the log level to Logger::ERROR for the whole broadcast.
error?() Link
True
if the log level allows entries with severity Logger::ERROR to be written to at least one broadcast. False
otherwise.
fatal(...) Link
fatal!() Link
Sets the log level to Logger::FATAL for the whole broadcast.
fatal?() Link
True
if the log level allows entries with severity Logger::FATAL to be written to at least one broadcast. False
otherwise.
formatter=(formatter) Link
info(...) Link
info!() Link
Sets the log level to Logger::INFO for the whole broadcast.
info?() Link
True
if the log level allows entries with severity Logger::INFO to be written to at least one broadcast. False
otherwise.
initialize_copy(other) Link
level() Link
local_level=(level) Link
stop_broadcasting_to(logger) Link
Remove a logger from the broadcast. When a logger is removed, messages sent to the broadcast will no longer be written to its sink.
sink = Logger.new(STDOUT)
broadcast_logger = ActiveSupport::BroadcastLogger.new
broadcast_logger.stop_broadcasting_to(sink)
unknown(...) Link
warn(...) Link
warn!() Link
Sets the log level to Logger::WARN for the whole broadcast.