Servtrics

Nodejs service metrics using InfluxDB

Usage

Servtrics = require('servtrics').default

Servtrics try to connect to Influx DB on import using the following enviromental variables:
NODE_METRICS_HOST: Influx database instance URI

NODE_METRICS_DATABASE: Influx database name

If you need to manually trigger the connection, simply use the connect method, without defining the previous variables.

Servtrics.connect(host, database = 'servtrics')

Create database given by name, if non existant, and attempt to connect to given host instance. Returns a promise which resolves after connecting or rejects after failing to connect.

Example:

Servtrics = require('servtrics')
Servtrics.connect("http://localhost:8086", "myServiceDB")

Servtrics.expressMetricsMiddleware(request, response, next)

Middleware function for measuring Express endpoints response times. Metrics are saved under express_response_times measurement. Stored fields and tags are the following:

{
    measurement: 'express_response_times',
    fields: {
        mean: FieldType.INTEGER,
        count: FieldType.INTEGER,
        upper: FieldType.INTEGER,
        sum: FieldType.INTEGER,
    },
    tags: [
        'path',
        'method',
        'status_code',
        'outcome'
    ]
}

Currently does not support measurements aggregations, despite the syntax.

Example:

Servtrics = require('servtrics')
express = require('express')

const app = express()

app.use(Servtrics.expressMetricsMiddleware);

Servtrics.metrifyAsynchronousFunction(asynchronousFunction)

Promise wrapper for metrifying asynchronous functions. Metrics are saved under promise_response_times. Stored fields and tags are the following:

{
    measurement: 'promise_response_times',
    fields: {
        mean: FieldType.INTEGER,
        count: FieldType.INTEGER,
        upper: FieldType.INTEGER,
        sum: FieldType.INTEGER,
    },
    tags: [
        'asynchronousFunction',
        'exception',
        'outcome'
    ]
}

Currently does not support measurements aggregations, despite the syntax.

Example:

Servtrics = require('servtrics')

const myAsynchronousFunction = (x) => Promise.resolve(x)
const myMetrifiedAsynchronousFunction = Servtrics.metrifyAsynchronousFunction(myAsynchronousFunction)

myMetrifiedAsynchronousFunction() 

Servtrics.metrifyFetch(fetch)

Fetch wrapper for metrifying asynchronous requests. Metrics are saved under fetch_response_times. Stored fields and tags are the following:

{
    measurement: 'fetch_response_times',
    fields: {
        mean: FieldType.INTEGER,
        count: FieldType.INTEGER,
        upper: FieldType.INTEGER,
        sum: FieldType.INTEGER,
    },
    tags: [
        'url',
        'method',
        'status_code',
        'outcome'
    ]
}

Currently does not support measurements aggregations, despite the syntax.

Example:

Servtrics = require('servtrics')
IsomorphicFetch = require('isomorphic-fetch')

const metrifiedFetch = Servtrics.metrifyFetch(IsomorphicFetch)

metrifiedFetch('https://google.com.br')