docs/lib/hydro.js

100 строки
2.7 KiB
JavaScript

const crypto = require('crypto')
const fetch = require('node-fetch')
const statsd = require('../lib/statsd')
const FailBot = require('../lib/failbot')
const SCHEMAS = {
page: 'docs.v0.PageEvent',
exit: 'docs.v0.ExitEvent',
link: 'docs.v0.LinkEvent',
search: 'docs.v0.SearchEvent',
navigate: 'docs.v0.NavigateEvent',
survey: 'docs.v0.SurveyEvent',
experiment: 'docs.v0.ExperimentEvent',
redirect: 'docs.v0.RedirectEvent',
clipboard: 'docs.v0.ClipboardEvent',
print: 'docs.v0.PrintEvent',
preference: 'docs.v0.PreferenceEvent'
}
module.exports = class Hydro {
constructor ({ secret, endpoint } = {}) {
this.secret = secret || process.env.HYDRO_SECRET
this.endpoint = endpoint || process.env.HYDRO_ENDPOINT
this.schemas = SCHEMAS
}
/**
* Can check if it can actually send to Hydro
*/
maySend () {
return Boolean(this.secret && this.endpoint)
}
/**
* Generate a SHA256 hash of the payload using the secret
* to authenticate with Hydro
* @param {string} body
*/
generatePayloadHmac (body) {
return crypto.createHmac('sha256', this.secret)
.update(body)
.digest('hex')
}
/**
* Publish a single event to Hydro
* @param {string} schema
* @param {any} value
*/
async publish (schema, value) {
return this.publishMany([{ schema, value }])
}
/**
* Publish multiple events to Hydro
* @param {[{ schema: string, value: any }]} events
*/
async publishMany (events) {
const body = JSON.stringify({
events: events.map(({ schema, value }) => ({
schema,
value: JSON.stringify(value), // We must double-encode the value property
cluster: 'potomac' // We only have ability to publish externally to potomac cluster
}))
})
const token = this.generatePayloadHmac(body)
const doFetch = () => fetch(this.endpoint, {
method: 'POST',
body,
headers: {
Authorization: `Hydro ${token}`,
'Content-Type': 'application/json',
'X-Hydro-App': 'docs-production'
}
})
const res = await statsd.asyncTimer(doFetch, 'hydro.response_time')()
const statTags = [`response_code:${res.status}`]
statsd.increment(`hydro.response_code.${res.status}`, 1, statTags)
statsd.increment('hydro.response_code.all', 1, statTags)
// Track hydro exceptions in Sentry, but don't track 503s because we can't do anything about service availability
if (!res.ok && res.status !== 503) {
const err = new Error(`Hydro request failed: ${res.statusText}`)
err.status = res.status
FailBot.report(err, {
hydroStatus: res.status,
hydroText: res.statusText
})
throw err
}
return res
}
}