npm install @inctasoft/simple-log-ts
-
debug
,info
,warn
,error
andcrit
methods. - JSON format, useful for log ingesting services
-
Error
,Map
Set
objects are trnsformed into JSON and also printed - In case of circular references, output is still JSON, and the message property will contain a string with the value of
util.inspect(data, ...inspectOptions)
.inspectOptions
by default is{}
but can be overwritten in Log's constructor - Optional
correlation_id
can be passed to constructor. Useful for correlating logs from different services. PassprintCorrelation: false
in Log's constructor to skip it.
- Empty config
import { Log } from "@inctasoft/simple-log-ts";
const log = new Log();
log.error("something hapened", new Error('some err msg'));
results in:
{"timestamp":"2023-10-11T21:50:47.405Z","level":"ERROR","message":"something hapened","correlation":"undefined","[Error]":{"stack":"Error: some err msg\n at Object..(the err stack)","message":"some err msg"}}```
- Log complex objects, provide
correlation_id
import { Log } from "@inctasoft/simple-log-ts";
process.env.LOGLEVEL = 'DEBUG' // default level is WARN, un-silence debug method
const log = new Log({ correlation_id: 'some_guid' });
log.debug({
a: 1, b: 'xyz', my_set: new Set(['foo', 'bar']), nested: {
my_arr: [
'elem1',
new Map([['mapKey', {
prop1: 1,
prop2: new Date()
}]])]
}
});
results in:
{"timestamp":"2023-10-12T00:14:44.139Z","level":"DEBUG","message":{"a":1,"b":"xyz","my_set":["foo","bar"],"nested":{"my_arr":["elem1",{"mapKey":{"prop1":1,"prop2":"2023-10-12T00:14:44.139Z"}}]}},"correlation":"some_guid"}
- If you are interested in which transformed objects were of
Map
orSet
types, provideprintMapSetTypes: true
-
Error
objects are always printed as{"[Error]": {stack:"...", message: "..."}}
- If you are not into using correlation_id, provide
printCorrelation: false
import { Log } from "@inctasoft/simple-log-ts";
const log = new Log({ printMapSetTypes: true, printCorrelation: false});
log.error({
a: 1, b: 'xyz', my_set: new Set(['foo', 'bar']), nested: {
my_arr: [
'elem1',
new Map([['mapKey', {
prop1: 1,
prop2: new Date()
}]])]
}
}, new Error("oops something unexpected happened"));
results in:
{"timestamp":"2023-10-12T01:57:31.983Z","level":"ERROR","message":{"a":1,"b":"xyz","my_set":{"[Set]":["foo","bar"]},"nested":{"my_arr":["elem1",{"[Map]":{"mapKey":{"prop1":1,"prop2":"2023-10-12T01:57:31.983Z"}}}]}},"[Error]":{"stack":"Error: oops something unexpected happened\n at Object..(the err stack)","message":"oops something unexpected happened"}}
- Circular reference handlig
import { Log } from "../src/log";
const obj: any = {};
obj.a = [obj];
obj.b = {};
obj.b.inner = obj.b;
obj.b.obj = obj;
new Log().warn(obj)
results in:
{"timestamp":"2023-10-14T05:59:48.714Z","level":"WARN","message":"<ref *1> {\n a: [ [Circular *1] ],\n b: <ref *2> { inner: [Circular *2], obj: [Circular *1] }\n}","correlation":"undefined"}
process.env.LOGLEVEL | active methods | notes |
---|---|---|
DEBUG |
debug ,info ,warn ,error ,crit
|
|
INFO |
info ,warn ,error ,crit
|
|
WARN |
warn ,error ,crit
|
default, if no LOGLEVEL is present |
ERROR |
error ,crit
|
Both crit and error use console.error and accept optional second Error argument |
SILENT (or any other value) |
crit |
Lets you silence all logs, if not using crit method(as it is always active, no matter of LOGLEVEL value) |