@rearc/noop-log
v1.0.2
Published
Simple JSON logger for Noop components
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noop-log
JS logging library for Noop components following Noop standard JSON format. The library is very simple and allows mixed types to be output easily (strings, objects, and Errors). This library is hosted publicly on NPM.
Quickstart
npm install @rearc/noop-log --save
const log = require('@rearc/noop-log')
log.info('something happened', 'over here', {id: 42}, new Error('damn'))
This outputs a single line JSON object with all the arguments above like:
{"level":"info","date":"2018-03-16T19:20:13.951Z","id":42,"inner":{"message":"damn","stack":"Error: damn\n at repl:1:55\n at sigintHandlersWrap (vm.js:22:35)\n at sigintHandlersWrap (vm.js:73:12)\n at ContextifyScript.Scr
ipt.runInThisContext (vm.js:21:12)\n at REPLServer.defaultEval (repl.js:340:29)\n at bound (domain.js:280:14)\n at REPLServer.runBound [as eval] (domain.js:293:12)\n at REPLServer.<anonymous> (repl.js:538:10)\n at emit
One (events.js:101:20)\n at REPLServer.emit (events.js:188:7)"},"msg":"something happened over here"}
Log Levels
The log output level defaults to info
but can be configured through the
LOG_LEVEL
environment variable. The available levels in order of severity are:
log.debug()
log.info()
log.warn()
log.error()
log.fatal()
Argument Types
All logging functions accept unlimited arguments of the string
, object
, and
Error
types.
string
all strings provided as arguments will be concatenated (in the order provided) into themsg
property of the output eventobject
all object types provided as arguments result in their properties being added to the output event.log.info({id: 42, name: 'foo'})
will result in the output event having theid
andname
properties applied. This also includes deep objects.Error
all JS Error object types will be have their details added to theinner
property of the output event. This fits the common case of recording the details of a lower level error along with your own message.