deno-logger
logger for deno
Update
v1.1.0 - 2023.05.04
Remove useless parameter and optimize fileLogger
interface fileLoggerOptions {
rotate?: boolean; // cut by day
- now?: boolean; // print datetime or not
maxBytes?: number, // the maximum size in bytes that the log file can grow to before rolling over to a new one
maxBackupCount?: number // maxBackupCount must work with maxBytes
}
v1.0.3 - 2023.05.04
update code to support modern Deno.
Logger interface
interface fileLoggerOptions {
rotate?: boolean; // cut by day
maxBytes?: number, // the maximum size in bytes that the log file can grow to before rolling over to a new one
maxBackupCount?: number // maxBackupCount must work with maxBytes
}
interface LoggerInerface {
constructor()
info(...args: unknown[]): void
warn(...args: unknown[]): void
error(...args: unknown[]): void
async initFileLogger(dir: string, options: fileLoggerOptions = {}): Promise<void>
disableConsole(): void
enableConsole(): void
disableFile(): void;
enableFile(): void;
disable(): void;
enable(): void;
}
Useage
console logger
import Logger from "https://deno.land/x/logger@v1.1.0/logger.ts";
const logger = new Logger();
logger.info("i am from consoleLogger", { name: "zfx" });
logger.warn("i am from consoleLogger", 1, "any");
logger.error("i am from consoleLogger", new Error("test"));
file and console logger
import Logger from "https://deno.land/x/logger@v1.1.0/logger.ts";
const logger = new Logger();
// console only
logger.info("i am from consoleLogger", { name: "zfx" });
logger.warn("i am from consoleLogger", 1, "any");
logger.error("i am from consoleLogger", new Error("test"));
await logger.initFileLogger("../log");
// file and console
logger.info("i am from fileLogger", { name: "zfx" });
logger.warn("i am from fileLogger", 1, "any");
logger.error("i am from fileLogger", new Error("test"));
file logger only
import Logger from "https://deno.land/x/logger@v1.1.0/logger.ts";
const logger = new Logger();
await logger.initFileLogger("../log");
logger.disableConsole();
// file only
logger.info(["i am from fileLogger", 1], { name: "zfx" });
file logger optional parameter
interface
interface fileLoggerOptions {
rotate?: boolean; // cut by day
maxBytes?: number;
// Only available if maxBytes is provided, Otherwise you will get an error
maxBackupCount?: number;
}
example
import Logger from "https://deno.land/x/logger@v1.1.0/logger.ts";
const logger = new Logger();
// cut by day
// filename is [date]_[type].log
// example 2020-05-25_warn.log, 2020-05-25_info.log, 2020-05-25_error.log
await logger.initFileLogger("../log", {
rotate: true,
});
// maxBytes
// filename is [type].log.[timestamp]
// example: info.log.1590374415956
await logger.initFileLogger("../log", {
maxBytes: 10 * 1024,
});
// rotate and maxBytes
// filename is [date]_[type].log.[timestamp]
// example: 2020-05-25_info.log.1590374415956
await logger.initFileLogger("../log", {
rotate: true,
maxBytes: 10 * 1024,
});
// maxBytes and maxBackupCount
// filename is [type].log.[n]
// example info.log.1, info.log.2 ...
// when reach maxBackupCount, the [type].log.[maxBackupCount-1] will be overwrite
/*
detail:
`maxBytes` specifies the maximum size
in bytes that the log file can grow to before rolling over to a new one. If the
size of the new log message plus the current log file size exceeds `maxBytes`
then a roll over is triggered. When a roll over occurs, before the log message
is written, the log file is renamed and appended with `.1`. If a `.1` version
already existed, it would have been renamed `.2` first and so on. The maximum
number of log files to keep is specified by `maxBackupCount`. After the renames
are complete the log message is written to the original, now blank, file.
Example: Given `log.txt`, `log.txt.1`, `log.txt.2` and `log.txt.3`, a
`maxBackupCount` of 3 and a new log message which would cause `log.txt` to
exceed `maxBytes`, then `log.txt.2` would be renamed to `log.txt.3` (thereby
discarding the original contents of `log.txt.3` since 3 is the maximum number of
backups to keep), `log.txt.1` would be renamed to `log.txt.2`, `log.txt` would
be renamed to `log.txt.1` and finally `log.txt` would be created from scratch
where the new log message would be written.
*/
await logger.initFileLogger("../log", {
maxBytes: 10 * 1024,
maxBackupCount: 10,
});
// rotate and maxBytes and maxBackupCount
// filename is [date]_[type].log.[n]
// example 2020-05-25_info.log.1, 2020-05-25_info.log.2
// when reach maxBackupCount, the [type].log.[maxBackupCount-1] will be overwrite
await logger.initFileLogger("../log", {
rotate: true,
maxBytes: 10 * 1024,
maxBackupCount: 10,
});
// rotate and maxBackupCount
// maxBackupCount will be ignored
await logger.initFileLogger("../log", {
rotate: true,
maxBackupCount: 10,
});
The following conditions will throw an error
// maxBackupCount
// get error => maxBackupCount must work with maxBytes
await logger.initFileLogger("../log", {
maxBackupCount: 10,
});
// rotate and maxBackupCount
// get error => maxBackupCount must work with maxBytes
await logger.initFileLogger("../log", {
rotate: true,
maxBackupCount: 10,
});
disableConsole and enableConsole
import Logger from "https://deno.land/x/logger@v1.1.0/logger.ts";
const logger = new Logger();
// console
logger.info("console enabled, you can see me");
logger.disableConsole();
// no message is logged
logger.info("console disabled");
logger.enableConsole();
// console
logger.info("console enabled, you can see me");
disableFile and enableFile
import Logger from "https://deno.land/x/logger@v1.1.0/logger.ts";
const logger = new Logger();
await logger.initFileLogger("../log");
logger.disableFile();
// not log to file
logger.info("file disbaled");
logger.enableFile();
// log to file
logger.info("file enabled, you can see me");
disable and enable
- disable disable write to file and terminal, don't care if it is currently writing to a file or terminal, but hope to restore the currently configuration later
- enable restore previous log configuration: file, terminal or both
example:
- fileLogger => disable => enable => fileLogger
- consoleLogger => disable => enable => consoleLogger
- fileLogger, consoleLogger => disable => enable => fileLogger, consoleLogger
import Logger from "https://deno.land/x/logger@v1.1.0/logger.ts";
const logger = new Logger();
await logger.initFileLogger("../log");
logger.disable();
logger.enable();
test
deno test --allow-read --allow-write
Screenshots
consoleLogger
fileLogger
cut logs by day
More screenshots in the screenshots
folder.