diff options
Diffstat (limited to 'lib/pure/logging.nim')
| -rw-r--r-- | lib/pure/logging.nim | 164 |
1 files changed, 108 insertions, 56 deletions
diff --git a/lib/pure/logging.nim b/lib/pure/logging.nim index 2e79cd3ca..c30f68af8 100644 --- a/lib/pure/logging.nim +++ b/lib/pure/logging.nim @@ -17,10 +17,11 @@ ## ## To get started, first create a logger: ## -## .. code-block:: -## import logging +## ```Nim +## import std/logging ## ## var logger = newConsoleLogger() +## ``` ## ## The logger that was created above logs to the console, but this module ## also provides loggers that log to files, such as the @@ -30,9 +31,10 @@ ## Once a logger has been created, call its `log proc ## <#log.e,ConsoleLogger,Level,varargs[string,]>`_ to log a message: ## -## .. code-block:: +## ```Nim ## logger.log(lvlInfo, "a log message") ## # Output: INFO a log message +## ``` ## ## The ``INFO`` within the output is the result of a format string being ## prepended to the message, and it will differ depending on the message's @@ -45,11 +47,10 @@ ## ``levelThreshold`` field and the global log filter. The latter can be changed ## with the `setLogFilter proc<#setLogFilter,Level>`_. ## -## **Warning:** -## * For loggers that log to a console or to files, only error and fatal -## messages will cause their output buffers to be flushed immediately. -## Use the `flushFile proc <io.html#flushFile,File>`_ to flush the buffer -## manually if needed. +## .. warning:: +## For loggers that log to a console or to files, only error and fatal +## messages will cause their output buffers to be flushed immediately by default. +## set ``flushThreshold`` when creating the logger to change this. ## ## Handlers ## -------- @@ -59,8 +60,8 @@ ## used with the `addHandler proc<#addHandler,Logger>`_, which is demonstrated ## in the following example: ## -## .. code-block:: -## import logging +## ```Nim +## import std/logging ## ## var consoleLog = newConsoleLogger() ## var fileLog = newFileLogger("errors.log", levelThreshold=lvlError) @@ -69,17 +70,19 @@ ## addHandler(consoleLog) ## addHandler(fileLog) ## addHandler(rollingLog) +## ``` ## ## After doing this, use either the `log template ## <#log.t,Level,varargs[string,]>`_ or one of the level-specific templates, ## such as the `error template<#error.t,varargs[string,]>`_, to log messages ## to all registered handlers at once. ## -## .. code-block:: +## ```Nim ## # This example uses the loggers created above ## log(lvlError, "an error occurred") ## error("an error occurred") # Equivalent to the above line ## info("something normal happened") # Will not be written to errors.log +## ``` ## ## Note that a message's level is still checked against each handler's ## ``levelThreshold`` and the global log filter. @@ -117,12 +120,13 @@ ## ## The following example illustrates how to use format strings: ## -## .. code-block:: -## import logging +## ```Nim +## import std/logging ## ## var logger = newConsoleLogger(fmtStr="[$time] - $levelname: ") ## logger.log(lvlInfo, "this is a message") ## # Output: [19:50:13] - INFO: this is a message +## ``` ## ## Notes when using multiple threads ## --------------------------------- @@ -142,9 +146,12 @@ ## * `strscans module<strscans.html>`_ for ``scanf`` and ``scanp`` macros, which ## offer easier substring extraction than regular expressions -import strutils, times +import std/[strutils, times] when not defined(js): - import os + import std/os + +when defined(nimPreviewSlimSystem): + import std/syncio type Level* = enum ## \ @@ -197,6 +204,15 @@ const ## If a different format string is preferred, refer to the ## `documentation about format strings<#basic-usage-format-strings>`_ ## for more information, including a list of available variables. + defaultFlushThreshold = when NimMajor >= 2: + when defined(nimV1LogFlushBehavior): lvlError else: lvlAll + else: + when defined(nimFlushAllLogs): lvlAll else: lvlError + ## The threshold above which log messages to file-like loggers + ## are automatically flushed. + ## + ## By default, only error and fatal messages are logged, + ## but defining ``-d:nimFlushAllLogs`` will make all levels be flushed type Logger* = ref object of RootObj @@ -225,6 +241,8 @@ type ## * `FileLogger<#FileLogger>`_ ## * `RollingFileLogger<#RollingFileLogger>`_ useStderr*: bool ## If true, writes to stderr; otherwise, writes to stdout + flushThreshold*: Level ## Only messages that are at or above this + ## threshold will be flushed immediately when not defined(js): type @@ -240,13 +258,15 @@ when not defined(js): ## * `ConsoleLogger<#ConsoleLogger>`_ ## * `RollingFileLogger<#RollingFileLogger>`_ file*: File ## The wrapped file + flushThreshold*: Level ## Only messages that are at or above this + ## threshold will be flushed immediately RollingFileLogger* = ref object of FileLogger ## A logger that writes log messages to a file while performing log ## rotation. ## ## Create a new ``RollingFileLogger`` with the `newRollingFileLogger proc - ## <#newRollingFileLogger,FileMode,int,int>`_. + ## <#newRollingFileLogger,FileMode,Positive,int>`_. ## ## **Note:** This logger is not available for the JavaScript backend. ## @@ -287,6 +307,7 @@ proc substituteLog*(frmt: string, level: Level, runnableExamples: doAssert substituteLog(defaultFmtStr, lvlInfo, "a message") == "INFO a message" doAssert substituteLog("$levelid - ", lvlError, "an error") == "E - an error" + doAssert substituteLog("$levelid", lvlDebug, "error") == "Derror" var msgLen = 0 for arg in args: msgLen += arg.len @@ -300,7 +321,7 @@ proc substituteLog*(frmt: string, level: Level, inc(i) var v = "" let app = when defined(js): "" else: getAppFilename() - while frmt[i] in IdentChars: + while i < frmt.len and frmt[i] in IdentChars: v.add(toLowerAscii(frmt[i])) inc(i) case v @@ -344,8 +365,8 @@ method log*(logger: ConsoleLogger, level: Level, args: varargs[string, `$`]) = ## `setLogFilter proc<#setLogFilter,Level>`_. ## ## **Note:** Only error and fatal messages will cause the output buffer - ## to be flushed immediately. Use the `flushFile proc - ## <io.html#flushFile,File>`_ to flush the buffer manually if needed. + ## to be flushed immediately by default. Set ``flushThreshold`` when creating + ## the logger to change this. ## ## See also: ## * `log method<#log.e,FileLogger,Level,varargs[string,]>`_ @@ -356,14 +377,15 @@ method log*(logger: ConsoleLogger, level: Level, args: varargs[string, `$`]) = ## ## **Examples:** ## - ## .. code-block:: + ## ```Nim ## var consoleLog = newConsoleLogger() ## consoleLog.log(lvlInfo, "this is a message") ## consoleLog.log(lvlError, "error code is: ", 404) + ## ``` if level >= logging.level and level >= logger.levelThreshold: let ln = substituteLog(logger.fmtStr, level, args) when defined(js): - let cln: cstring = ln + let cln = ln.cstring case level of lvlDebug: {.emit: "console.debug(`cln`);".} of lvlInfo: {.emit: "console.info(`cln`);".} @@ -376,12 +398,12 @@ method log*(logger: ConsoleLogger, level: Level, args: varargs[string, `$`]) = if logger.useStderr: handle = stderr writeLine(handle, ln) - if level in {lvlError, lvlFatal}: flushFile(handle) + if level >= logger.flushThreshold: flushFile(handle) except IOError: discard proc newConsoleLogger*(levelThreshold = lvlAll, fmtStr = defaultFmtStr, - useStderr = false): ConsoleLogger = + useStderr = false, flushThreshold = defaultFlushThreshold): ConsoleLogger = ## Creates a new `ConsoleLogger<#ConsoleLogger>`_. ## ## By default, log messages are written to ``stdout``. If ``useStderr`` is @@ -394,17 +416,19 @@ proc newConsoleLogger*(levelThreshold = lvlAll, fmtStr = defaultFmtStr, ## * `newFileLogger proc<#newFileLogger,File>`_ that uses a file handle ## * `newFileLogger proc<#newFileLogger,FileMode,int>`_ ## that accepts a filename - ## * `newRollingFileLogger proc<#newRollingFileLogger,FileMode,int,int>`_ + ## * `newRollingFileLogger proc<#newRollingFileLogger,FileMode,Positive,int>`_ ## ## **Examples:** ## - ## .. code-block:: + ## ```Nim ## var normalLog = newConsoleLogger() ## var formatLog = newConsoleLogger(fmtStr=verboseFmtStr) ## var errorLog = newConsoleLogger(levelThreshold=lvlError, useStderr=true) + ## ``` new result result.fmtStr = fmtStr result.levelThreshold = levelThreshold + result.flushThreshold = flushThreshold result.useStderr = useStderr when not defined(js): @@ -420,8 +444,8 @@ when not defined(js): ## ## **Notes:** ## * Only error and fatal messages will cause the output buffer - ## to be flushed immediately. Use the `flushFile proc - ## <io.html#flushFile,File>`_ to flush the buffer manually if needed. + ## to be flushed immediately by default. Set ``flushThreshold`` when creating + ## the logger to change this. ## * This method is not available for the JavaScript backend. ## ## See also: @@ -433,13 +457,14 @@ when not defined(js): ## ## **Examples:** ## - ## .. code-block:: + ## ```Nim ## var fileLog = newFileLogger("messages.log") ## fileLog.log(lvlInfo, "this is a message") ## fileLog.log(lvlError, "error code is: ", 404) + ## ``` if level >= logging.level and level >= logger.levelThreshold: writeLine(logger.file, substituteLog(logger.fmtStr, level, args)) - if level in {lvlError, lvlFatal}: flushFile(logger.file) + if level >= logger.flushThreshold: flushFile(logger.file) proc defaultFilename*(): string = ## Returns the filename that is used by default when naming log files. @@ -450,7 +475,8 @@ when not defined(js): proc newFileLogger*(file: File, levelThreshold = lvlAll, - fmtStr = defaultFmtStr): FileLogger = + fmtStr = defaultFmtStr, + flushThreshold = defaultFlushThreshold): FileLogger = ## Creates a new `FileLogger<#FileLogger>`_ that uses the given file handle. ## ## **Note:** This proc is not available for the JavaScript backend. @@ -459,11 +485,11 @@ when not defined(js): ## * `newConsoleLogger proc<#newConsoleLogger>`_ ## * `newFileLogger proc<#newFileLogger,FileMode,int>`_ ## that accepts a filename - ## * `newRollingFileLogger proc<#newRollingFileLogger,FileMode,int,int>`_ + ## * `newRollingFileLogger proc<#newRollingFileLogger,FileMode,Positive,int>`_ ## ## **Examples:** ## - ## .. code-block:: + ## ```Nim ## var messages = open("messages.log", fmWrite) ## var formatted = open("formatted.log", fmWrite) ## var errors = open("errors.log", fmWrite) @@ -471,16 +497,19 @@ when not defined(js): ## var normalLog = newFileLogger(messages) ## var formatLog = newFileLogger(formatted, fmtStr=verboseFmtStr) ## var errorLog = newFileLogger(errors, levelThreshold=lvlError) + ## ``` new(result) result.file = file result.levelThreshold = levelThreshold + result.flushThreshold = flushThreshold result.fmtStr = fmtStr proc newFileLogger*(filename = defaultFilename(), mode: FileMode = fmAppend, levelThreshold = lvlAll, fmtStr = defaultFmtStr, - bufSize: int = -1): FileLogger = + bufSize: int = -1, + flushThreshold = defaultFlushThreshold): FileLogger = ## Creates a new `FileLogger<#FileLogger>`_ that logs to a file with the ## given filename. ## @@ -495,16 +524,17 @@ when not defined(js): ## See also: ## * `newConsoleLogger proc<#newConsoleLogger>`_ ## * `newFileLogger proc<#newFileLogger,File>`_ that uses a file handle - ## * `newRollingFileLogger proc<#newRollingFileLogger,FileMode,int,int>`_ + ## * `newRollingFileLogger proc<#newRollingFileLogger,FileMode,Positive,int>`_ ## ## **Examples:** ## - ## .. code-block:: + ## ```Nim ## var normalLog = newFileLogger("messages.log") ## var formatLog = newFileLogger("formatted.log", fmtStr=verboseFmtStr) ## var errorLog = newFileLogger("errors.log", levelThreshold=lvlError) + ## ``` let file = open(filename, mode, bufSize = bufSize) - newFileLogger(file, levelThreshold, fmtStr) + newFileLogger(file, levelThreshold, fmtStr, flushThreshold) # ------ @@ -536,7 +566,8 @@ when not defined(js): levelThreshold = lvlAll, fmtStr = defaultFmtStr, maxLines: Positive = 1000, - bufSize: int = -1): RollingFileLogger = + bufSize: int = -1, + flushThreshold = defaultFlushThreshold): RollingFileLogger = ## Creates a new `RollingFileLogger<#RollingFileLogger>`_. ## ## Once the current log file being written to contains ``maxLines`` lines, @@ -558,11 +589,12 @@ when not defined(js): ## ## **Examples:** ## - ## .. code-block:: + ## ```Nim ## var normalLog = newRollingFileLogger("messages.log") ## var formatLog = newRollingFileLogger("formatted.log", fmtStr=verboseFmtStr) ## var shortLog = newRollingFileLogger("short.log", maxLines=200) ## var errorLog = newRollingFileLogger("errors.log", levelThreshold=lvlError) + ## ``` new(result) result.levelThreshold = levelThreshold result.fmtStr = fmtStr @@ -572,6 +604,7 @@ when not defined(js): result.curLine = 0 result.baseName = filename result.baseMode = mode + result.flushThreshold = flushThreshold result.logFiles = countFiles(filename) @@ -598,8 +631,8 @@ when not defined(js): ## ## **Notes:** ## * Only error and fatal messages will cause the output buffer - ## to be flushed immediately. Use the `flushFile proc - ## <io.html#flushFile,File>`_ to flush the buffer manually if needed. + ## to be flushed immediately by default. Set ``flushThreshold`` when creating + ## the logger to change this. ## * This method is not available for the JavaScript backend. ## ## See also: @@ -611,10 +644,11 @@ when not defined(js): ## ## **Examples:** ## - ## .. code-block:: + ## ```Nim ## var rollingLog = newRollingFileLogger("messages.log") ## rollingLog.log(lvlInfo, "this is a message") ## rollingLog.log(lvlError, "error code is: ", 404) + ## ``` if level >= logging.level and level >= logger.levelThreshold: if logger.curLine >= logger.maxLines: logger.file.close() @@ -625,7 +659,7 @@ when not defined(js): bufSize = logger.bufSize) writeLine(logger.file, substituteLog(logger.fmtStr, level, args)) - if level in {lvlError, lvlFatal}: flushFile(logger.file) + if level >= logger.flushThreshold: flushFile(logger.file) logger.curLine.inc # -------- @@ -644,11 +678,12 @@ template log*(level: Level, args: varargs[string, `$`]) = ## ## **Examples:** ## - ## .. code-block:: + ## ```Nim ## var logger = newConsoleLogger() ## addHandler(logger) ## ## log(lvlInfo, "This is an example.") + ## ``` ## ## See also: ## * `debug template<#debug.t,varargs[string,]>`_ @@ -673,11 +708,12 @@ template debug*(args: varargs[string, `$`]) = ## ## **Examples:** ## - ## .. code-block:: + ## ```Nim ## var logger = newConsoleLogger() ## addHandler(logger) ## ## debug("myProc called with arguments: foo, 5") + ## ``` ## ## See also: ## * `log template<#log.t,Level,varargs[string,]>`_ @@ -694,11 +730,12 @@ template info*(args: varargs[string, `$`]) = ## ## **Examples:** ## - ## .. code-block:: + ## ```Nim ## var logger = newConsoleLogger() ## addHandler(logger) ## ## info("Application started successfully.") + ## ``` ## ## See also: ## * `log template<#log.t,Level,varargs[string,]>`_ @@ -715,11 +752,12 @@ template notice*(args: varargs[string, `$`]) = ## ## **Examples:** ## - ## .. code-block:: + ## ```Nim ## var logger = newConsoleLogger() ## addHandler(logger) ## ## notice("An important operation has completed.") + ## ``` ## ## See also: ## * `log template<#log.t,Level,varargs[string,]>`_ @@ -735,11 +773,12 @@ template warn*(args: varargs[string, `$`]) = ## ## **Examples:** ## - ## .. code-block:: + ## ```Nim ## var logger = newConsoleLogger() ## addHandler(logger) ## ## warn("The previous operation took too long to process.") + ## ``` ## ## See also: ## * `log template<#log.t,Level,varargs[string,]>`_ @@ -757,11 +796,12 @@ template error*(args: varargs[string, `$`]) = ## ## **Examples:** ## - ## .. code-block:: + ## ```Nim ## var logger = newConsoleLogger() ## addHandler(logger) ## ## error("An exception occurred while processing the form.") + ## ``` ## ## See also: ## * `log template<#log.t,Level,varargs[string,]>`_ @@ -778,11 +818,12 @@ template fatal*(args: varargs[string, `$`]) = ## ## **Examples:** ## - ## .. code-block:: + ## ```Nim ## var logger = newConsoleLogger() ## addHandler(logger) ## ## fatal("Can't open database -- exiting.") + ## ``` ## ## See also: ## * `log template<#log.t,Level,varargs[string,]>`_ @@ -793,11 +834,12 @@ template fatal*(args: varargs[string, `$`]) = proc addHandler*(handler: Logger) = ## Adds a logger to the list of registered handlers. ## - ## **Warning:** The list of handlers is a thread-local variable. If the given - ## handler will be used in multiple threads, this proc should be called in - ## each of those threads. + ## .. warning:: The list of handlers is a thread-local variable. If the given + ## handler will be used in multiple threads, this proc should be called in + ## each of those threads. ## ## See also: + ## * `removeHandler proc`_ ## * `getHandlers proc<#getHandlers>`_ runnableExamples: var logger = newConsoleLogger() @@ -805,6 +847,16 @@ proc addHandler*(handler: Logger) = doAssert logger in getHandlers() handlers.add(handler) +proc removeHandler*(handler: Logger) = + ## Removes a logger from the list of registered handlers. + ## + ## Note that for n times a logger is registered, n calls to this proc + ## are required to remove that logger. + for i, hnd in handlers: + if hnd == handler: + handlers.delete(i) + return + proc getHandlers*(): seq[Logger] = ## Returns a list of all the registered handlers. ## @@ -819,10 +871,10 @@ proc setLogFilter*(lvl: Level) = ## individual logger's ``levelThreshold``. By default, all messages are ## logged. ## - ## **Warning:** The global log filter is a thread-local variable. If logging - ## is being performed in multiple threads, this proc should be called in each - ## thread unless it is intended that different threads should log at different - ## logging levels. + ## .. warning:: The global log filter is a thread-local variable. If logging + ## is being performed in multiple threads, this proc should be called in each + ## thread unless it is intended that different threads should log at different + ## logging levels. ## ## See also: ## * `getLogFilter proc<#getLogFilter>`_ |