@opencensus/core (0.0.8)
Installation
@opencensus:registry=npm install @opencensus/core@0.0.8"@opencensus/core": "0.0.8"About this package
OpenCensus Core Node.js
OpenCensus for Node.js is an implementation of OpenCensus, a toolkit for collecting application performance and behavior monitoring data. It currently includes 3 apis: stats, tracing and tags.
The library is in alpha stage and the API is subject to change.
Installation
Install the opencensus-core package with NPM:
npm install @opencensus/core
Usage
Set up a new Stats manager instance.
To enable metrics, we’ll import a few items from OpenCensus Core package.
const { Stats, MeasureUnit, AggregationType } = require('@opencensus/core');
// Create the Stats manager
const stats = new Stats();
// The latency in milliseconds
const mLatencyMs = stats.createMeasureDouble(
"repl/latency",
MeasureUnit.MS,
"The latency in milliseconds"
);
Create Views and Tags:
We now determine how our metrics will be organized by creating Views. We will also create the variable needed to add extra text meta-data to our metrics – methodTagKey, statusTagKey, and errorTagKey.
const methodTagKey = "method";
const statusTagKey = "status";
const errorTagKey = "error";
const latencyView = stats.createView(
"demo/latency",
mLatencyMs,
AggregationType.DISTRIBUTION,
[methodTagKey, statusTagKey, errorTagKey],
"The distribution of the latencies",
// Bucket Boundaries:
// [>=0ms, >=25ms, >=50ms, >=75ms, >=100ms, >=200ms, >=400ms, >=600ms, >=800ms, >=1s, >=2s, >=4s, >=6s]
[0, 25, 50, 75, 100, 200, 400, 600, 800, 1000, 2000, 4000, 6000]
);
Recording Metrics:
Now we will record the desired metrics. To do so, we will use stats.record() and pass in measurements.
const [_, startNanoseconds] = process.hrtime();
const tags = {method: "repl", status: "OK"};
stats.record({
measure: mLatencyMs,
tags,
value: sinceInMilliseconds(startNanoseconds)
});
function sinceInMilliseconds(startNanoseconds) {
const [_, endNanoseconds] = process.hrtime();
return (endNanoseconds - startNanoseconds) / 1e6;
}
See Quickstart/Metrics for a full example of registering and collecting metrics.
Useful links
- For more information on OpenCensus, visit: https://opencensus.io/
- To checkout the OpenCensus for Node.js, visit: https://github.com/census-instrumentation/opencensus-node
- For help or feedback on this project, join us on gitter
LICENSE
Apache License 2.0
Dependencies
Dependencies
| ID | Version |
|---|---|
| continuation-local-storage | ^3.2.1 |
| log-driver | ^1.2.7 |
| semver | ^5.5.0 |
| shimmer | ^1.2.0 |
| uuid | ^3.2.1 |
Development Dependencies
| ID | Version |
|---|---|
| @types/continuation-local-storage | ^3.2.1 |
| @types/mocha | ^5.2.5 |
| @types/node | ^10.12.12 |
| @types/once | ^1.4.0 |
| @types/semver | ^5.5.0 |
| @types/shimmer | ^1.0.1 |
| @types/uuid | ^3.4.3 |
| gts | ^0.9.0 |
| intercept-stdout | ^0.1.2 |
| mocha | ^5.0.4 |
| ncp | ^2.0.0 |
| nyc | 11.6.0 |
| ts-node | ^7.0.1 |
| typescript | ~2.6.1 |