Cli.Extras.Logging

Provides a logging handler that facilitates safe ouputting to terminal using MVar based locking. | Spinner.hs and Process.hs work on this guarantee.

Documentation

class AsUnstructuredError e where

Indicates unstructured errors form one variant (or conceptual projection) of the error type.

Shouldn't really use this, but who has time to clean up that much!

Methods

asUnstructuredError :: Prism' e Text

Instances

AsUnstructuredError Text

Defined in Cli.Extras.Logging

Methods

asUnstructuredError :: Prism' Text Text

newCliConfig

Arguments

:: Severity

The initial log level. Messages below this severity will not be logged, unless the log level is subsequently altered using setLogLevel.

-> Bool

Should ANSI terminal formatting be disabled?

-> Bool

Should spinners be disabled?

-> (e -> (Text, ExitCode))

How to display errors, and compute the ExitCode corresponding to each error.

-> IO (CliConfig e)

Create a new CliConfig, initialized with the provided values.

runCli :: MonadIO m => CliConfig e -> CliT e m a -> m a

verboseLogLevel :: Severity

isOverwrite :: Output -> Bool

getSeverity :: Output -> Maybe Severity

getLogLevel :: (MonadIO m, HasCliConfig e m) => m Severity

setLogLevel :: (MonadIO m, HasCliConfig e m) => Severity -> m ()

putLog :: CliLog m => Severity -> Text -> m ()

Log a message to the console.

The message is guaranteed to be logged uninterrupted, even if there are ongoing spinners.

putLogRaw :: CliLog m => Severity -> Text -> m ()

Like putLog but without the implicit newline added.

failWith :: (CliThrow e m, AsUnstructuredError e) => Text -> m a

Like `putLog Alert` but also abrupts the program.

errorToWarning :: (HasCliConfig e m, CliLog m) => e -> m ()

Log an error as though it were a warning, in a non-fatal way.

withExitFailMessage :: (CliLog m, MonadCatch m) => Text -> m a -> m a

Intercept ExitFailure exceptions and log the given alert before exiting.

This is useful when you want to provide contextual information to a deeper failure.

writeLog

Arguments

:: MonadIO m

=> Bool

Should a new line be printed after the message?

-> Bool

Should ANSI terminal formatting be used when printing the message?

-> WithSeverity Text

The message to print.

-> m ()

Log a message to standard output.

allowUserToMakeLoggingVerbose

Arguments

:: (MonadIO m, MonadMask m, CliLog m, HasCliConfig e m)

=> String

The key(s) which should be read to indicate a shift in verbosity.

-> Text

A description of the key that must be pressed.

-> m ()

Allows the user to immediately switch to verbose logging when a particular sequence of characters is read from the terminal.

Call this function in a thread, and kill it to turn off keystroke monitoring.

getChars :: IO String

Like getChar but also retrieves the subsequently pressed keys.

Allowing, for example, the ↑ key, which consists of the three characters ['ESC','[',A] to be distinguished from an actual ESC character input.

fork :: (HasCliConfig e m, MonadIO m) => CliT e IO () -> m ThreadId

Fork a computation in CliT, sharing the configuration with the child thread.