overleaf/libraries/metrics/test/unit/js/mongodb.js
Eric Mc Sween 74eeec2ba3 Merge pull request #11680 from overleaf/em-mongo-pool-monitoring
Mongo connection pool monitoring

GitOrigin-RevId: 050e50e7e67061ccbf39a710ca4532eafd423365
2023-02-09 14:34:35 +00:00

89 lines
2.7 KiB
JavaScript

const Metrics = require('../../..')
const { expect } = require('chai')
const prom = require('prom-client')
describe('mongodb', function () {
beforeEach(function () {
prom.register.clear()
this.pool = {
totalConnectionCount: 8,
availableConnectionCount: 2,
waitQueueSize: 4,
options: { maxPoolSize: 10 },
}
this.servers = new Map([['server1', { s: { pool: this.pool } }]])
this.mongoClient = { topology: { s: { servers: this.servers } } }
})
it('handles an unconnected client', async function () {
const mongoClient = {}
Metrics.mongodb.monitor(mongoClient)
const metrics = await getMetrics()
expect(metrics).to.deep.equal({})
})
it('collects Mongo metrics', async function () {
Metrics.mongodb.monitor(this.mongoClient)
const metrics = await getMetrics()
expect(metrics).to.deep.equal({
'mongo_connection_pool_max:server1': 10,
'mongo_connection_pool_size:server1': 8,
'mongo_connection_pool_available:server1': 2,
'mongo_connection_pool_waiting:server1': 4,
})
})
it('handles topology changes', async function () {
Metrics.mongodb.monitor(this.mongoClient)
let metrics = await getMetrics()
expect(metrics).to.deep.equal({
'mongo_connection_pool_max:server1': 10,
'mongo_connection_pool_size:server1': 8,
'mongo_connection_pool_available:server1': 2,
'mongo_connection_pool_waiting:server1': 4,
})
// Add a server
this.servers.set('server2', this.servers.get('server1'))
metrics = await getMetrics()
expect(metrics).to.deep.equal({
'mongo_connection_pool_max:server1': 10,
'mongo_connection_pool_size:server1': 8,
'mongo_connection_pool_available:server1': 2,
'mongo_connection_pool_waiting:server1': 4,
'mongo_connection_pool_max:server2': 10,
'mongo_connection_pool_size:server2': 8,
'mongo_connection_pool_available:server2': 2,
'mongo_connection_pool_waiting:server2': 4,
})
// Delete a server
this.servers.delete('server1')
metrics = await getMetrics()
expect(metrics).to.deep.equal({
'mongo_connection_pool_max:server2': 10,
'mongo_connection_pool_size:server2': 8,
'mongo_connection_pool_available:server2': 2,
'mongo_connection_pool_waiting:server2': 4,
})
// Delete another server
this.servers.delete('server2')
metrics = await getMetrics()
expect(metrics).to.deep.equal({})
})
})
async function getMetrics() {
const metrics = await prom.register.getMetricsAsJSON()
const result = {}
for (const metric of metrics) {
for (const value of metric.values) {
const key = `${metric.name}:${value.labels.mongo_server}`
result[key] = value.value
}
}
return result
}