| Safe Haskell | None |
|---|---|
| Language | Haskell2010 |
Logging.Types
Synopsis
- type Logger = String
- newtype Level = Level Int
- newtype Filter = Filter Logger
- type Filterer = [Filter]
- data LogRecord = LogRecord {}
- data StreamHandler = StreamHandler {}
- data FileHandler = FileHandler {}
- data Sink = Sink {}
- data Manager = Manager {}
- class Filterable a where
- data SomeHandler where
- SomeHandler :: Handler h => h -> SomeHandler
- class (HasType Level a, HasType Filterer a, HasType Format1 a, Typeable a, Eq a) => Handler a where
Documentation
Level also known as severity, a higher Level means a bigger Int.
There are 5 common severity levels:
DEBUG- Level 10
INFO- Level 20
WARN- Level 30
ERROR- Level 40
FATAL- Level 50
>>>:set -XOverloadedStrings>>>"DEBUG" :: LevelDEBUG>>>"DEBUG" == (Level 10)True
Instances
| Enum Level Source # | |
Defined in Logging.Types.Level | |
| Eq Level Source # | |
| Ord Level Source # | |
| Read Level Source # | |
| Show Level Source # | |
| IsString Level Source # | |
Defined in Logging.Types.Level Methods fromString :: String -> Level # | |
| FromJSON Level Source # | |
| Default Level Source # | |
Defined in Logging.Types.Level | |
| FormatArg Level Source # | |
| HasType Level SomeHandler Source # | |
Defined in Logging.Types.Class.Handler Methods typed :: Lens SomeHandler SomeHandler Level Level # getTyped :: SomeHandler -> Level # setTyped :: Level -> SomeHandler -> SomeHandler # | |
Filters are used to perform arbitrary filtering of LogRecords.
Sinks and Handlers can optionally use Filter to filter records
as desired. It allows events which are below a certain point in the
sink hierarchy. For example, a filter initialized with A.B will allow
events logged by loggers A.B, A.B.C, A.B.C.D, A.B.D etc.
but not A.BB, B.A.B etc.
If initialized name with the empty string, all events are passed.
Instances
| Eq Filter Source # | |
| Read Filter Source # | |
| Show Filter Source # | |
| IsString Filter Source # | |
Defined in Logging.Types.Filter Methods fromString :: String -> Filter # | |
| FromJSON Filter Source # | |
| Filterable Filter Source # | |
| HasType Filterer SomeHandler Source # | |
Defined in Logging.Types.Class.Handler Methods typed :: Lens SomeHandler SomeHandler Filterer Filterer # getTyped :: SomeHandler -> Filterer # setTyped :: Filterer -> SomeHandler -> SomeHandler # | |
A LogRecord represents an event being logged.
LogRecords are created every time something is logged. They
contain all the information related to the event being logged.
It includes the main message as well as information such as when the record was created, the source line where the logging call was made.
LogRecord can be formatted into string by Format
from vformat package, see format1 for more information.
Currently, the useful attributes in a LogRecord are described by:
logger name of the logger, seeLoggerlevel logging level for the message, seeLevelmessage the main message passed to logv debug info .. pathname full pathname of the source file where the logging call was issued (if available) filename filename portion of pathname pkgname package name where the logging call was issued (if available) modulename module name (e.g. Main, Logging.Types) lineno source line number where the logging call was issued (if available) asctimeZonedTimewhen the LogRecord was created utctimeUTCTimewhen the LogRecord was created created timestamp when the LogRecord was created msecs millisecond portion of the creation time
Format examples:
"{message}"
"{logger} {level}: {message}"
"{logger:<20.20s} {level:<8s}: {message}"
"{asctime:%Y-%m-%dT%H:%M:%S%6Q%z} - {level} - {logger}] {message}"
Constructors
| LogRecord | |
Instances
data StreamHandler Source #
A handler type which writes logging records, appropriately formatted, to a stream.
Constructors
| StreamHandler | |
Instances
data FileHandler Source #
A handler type which writes logging records, appropriately formatted, to a file.
Constructors
| FileHandler | |
Instances
Sink represents a single logging channel.
A "logging channel" indicates an area of an application. Exactly how an "area" is defined is up to the application developer. Since an application can have any number of areas, logging channels are identified by a unique string. Application areas can be nested (e.g. an area of "input processing" might include sub-areas "read CSV files", "read XLS files" and "read Gnumeric files"). To cater for this natural nesting, channel names are organized into a namespace hierarchy where levels are separated by periods, much like the Haskell module namespace. So in the instance given above, channel names might be Input for the upper level, and Input.Csv, Input.Xls and Input.Gnu for the sub-levels. There is no arbitrary limit to the depth of nesting.
Note: The namespaces are case sensitive.
Constructors
| Sink | |
There is under normal circumstances just one Manager, which holds the hierarchy of sinks.
Constructors
| Manager | |
class Filterable a where Source #
A class represents a common trait of filtering LogRecords
Instances
| Filterable Filter Source # | |
| Filterable Sink Source # | |
| Filterable a => Filterable [a] Source # | |
data SomeHandler where Source #
The SomeHandler type is the root of the handler type hierarchy.
It holds the real Handler instance
Constructors
| SomeHandler :: Handler h => h -> SomeHandler |
Instances
class (HasType Level a, HasType Filterer a, HasType Format1 a, Typeable a, Eq a) => Handler a where Source #
A type class that abstracts the characteristics of a Handler
Note: Locking is not necessary, because Handle has done it on
handle operations.
Minimal complete definition
Methods
emit :: a -> LogRecord -> IO () Source #
handle :: a -> LogRecord -> IO Bool Source #
fromHandler :: SomeHandler -> Maybe a Source #
toHandler :: a -> SomeHandler Source #