Standard swift-log handler for cutelog.
Allows displaying local logs in a GUI with searching and filtering features (similar to NSLogger).
- pure Swift, works on all platforms where sockets are supported
- asynchronous, non-blocking logging
- automatically attempts to restore connection if lost
- supports metadata and namespaces (labels)
- suitable for tests with flushing and environment variables
- can send logs to multiple cutelog instances simultaneously
- Follow the instructions on the cutelog README
- install the MessagePack serializer with
pip install msgpack
- At the start of your app, create one
CutelogLoggerwith the desired address and port- You can give it its own logger if you want, to report any networking errors or failures
- You can also specify a custom
DispatchQueue
- Inside the
LoggingSystem.bootstrapfactory, callmakeHandler(label:logLevel:)to get aLogHandlerbound to this logger.
import Cutelog
import Logging
// Create the logger, this will initiate the remote connection
let cutelogLogger = CutelogLogger(
address: "127.0.0.1",
port: Cutelog.defaultPort,
internalLogger: nil // add one to display any networking errors or failures
)
// Will be called when a new `Logger` is created
LoggingSystem.bootstrap { label in
return cutelogLogger.makeHandler(label: label, logLevel: .info)
}
// Then use swift-log normally
let logger = Logger(label: "Demo")
logger.info("Hello world!")Warning The
LoggingSystem.bootstrapfactory will be called EVERY TIME a new logger is created - DO NOT create theCutelogLoggerin the factory, it will make a new connection for every new logger in your app. Instead, create the logger ONCE and then callmakeHandler(label:logLevel:)in the factory to get a handler bound to this logger.
To enable logs for testing you only need to bootstrap the logging system the same way that you do when running the app normally.
Since tests cannot have command line arguments, you can use environment variables instead to get the remote address and enable cutelog: CUTELOG_ADDRESS=127.0.0.1 LOGLEVEL=trace swift test.
Do this before calling XCTestMain and it should work out of the box.
Since swift-cutelog is buffered and asynchronous, tests usually complete before swift-cutelog finishes sending all the logs over. This results in truncated logs when the tests end (because there is no graceful exit).
To solve this problem, the logger has a flush() method that will synchronously flush the buffer and send all remaining logs to cutelog (if connected). This usually takes some time and clogs up cutelog.
As XCTestMain never returns 🙃 you will need to make a dummy test case that runs at the end just to flush the logger.
cutelog namespaces are mapped to swift-log logger labels.
You can use dots as a separator to make nested namespaces that show nicely in the cutelog sidebar: let logger = Logger(label: "MyApp.Engine.Physics"). That will show as MyApp > Engine > Physics inside cutelog.
Metadata is automatically sent to cutelog and will display in the bottom table when selecting a log entry.
You cannot have metadata with the following names as they are reserved:
namemessagelevelnamecreatedfilelinefunction
Conflicting metadata keys will be ignored.