@wisual/logger
v1.2.3
Published
This is a logging module for the front-end. At the moment it only implements simple creation of contextual and hierarchical loggers that carry over data through React.js context. It also implements some basic pretty-printing.
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@wisual/logger
This is a logging module for the front-end. At the moment it only implements simple creation of contextual and hierarchical loggers that carry over data through React.js context. It also implements some basic pretty-printing.
Basic usage
A logger can be created with LoggerFactory
. It'll be cached by name & thus getting the logger is very cheap.
import { LoggerFactory } from "@wisual/logger";
const logger = LoggerFactory.getLogger("MyLogger");
logger.info("Hello world");
logger.debug("segfault");
logger.warn("Coulnd't find X");
logger.error("Oh no");
Structured data
You may pass additional data as a parameter & this will be available for the sinks to output in a structured format:
logger.info("Created user", { user, sessionId, tabId });
Hierarchical logger
Loggers are hierarchical. When creating a child, you may set extra context data on to it. Every child will inherits it's parents contexes.
import { LoggerFactory } from "@wisual/logger";
const logger = LoggerFactory.getLogger("root");
const usersServiceLogger = logger.child('UsersService', { dbBackend: 'psql', flushTimeout: 1000 });
const usersCacheLogger = usersServiceLogger.child('UsersCache', { cacheBackend: 'redis' });
usersCacheLogger.info('Cache hits in last 10 seconds', { cacheHits: 10 });
// Data available in the log:
// {
// logger: "root>UsersService>UsersCache",
// message: "Cache hits in last 10 seconds",
// time: "01-03-2021T...",
// variables: { cacheHits: 10 },
// context: {
// dbBackend: 'psql',
// flushTimeout: 1000,
// cacheBackend: 'redis',
// }
// }
React integration
There are hooks provided for react integration.
import React from "react";
import { useLogger } from "@wisual/logger";
function MyComponent({ userId, data }: { userId: string; data: any }) {
// Creating our logger and properly setting its context
const logger = useLogger("MyComponent", { userId });
// Will log on render with proper context / names
logger.info("rendering");
// This will use effect to log & log everytime the arguments change
logger.onInfo("Data has changed", { data });
// This is wrapping the children with this logger's context provider
return logger.wrap(<div />);
}
The hierarchy of loggers will be created based on the React tree. A logger may wrap a sub-tree with wrapWithLogger:
function Router({ routeName }) {
const routerLogger = useLogger("Router", { routeName });
// ...
return wrapWithLogger(
routerLogger,
<div>...</div>
);
}
All calls to useLogger
within the wrapped sub-tree will inherit the parent context.
Logger sinks
Sinks are implementors of the LoggerSink
interface.
Tree sinks are provided:
PrettyConsoleSink
- Pretty print messages on Node.jsPrettyBrowserSink
- Pretty print messages on browser consoles, which have support for CSSDelegatingSink
- Send messages to multiple sinks
There's no filtering currently implemented.
In addition, you'll find a tauri
sink which provides rust/js logging functionality in the crates/plugin-host-gui
package.
Configuring the sink
Use LoggerFactory.setSink
.