diff --git a/core/base-service/base.js b/core/base-service/base.js
index 352314d8363f0188ab5edd73248b5473ece2f7a6..2d4dfdb644571acd29bee0f9af52a8060c876717 100644
--- a/core/base-service/base.js
+++ b/core/base-service/base.js
@@ -8,7 +8,7 @@ const emojic = require('emojic')
const Joi = require('@hapi/joi')
const log = require('../server/log')
const { AuthHelper } = require('./auth-helper')
-const { MetricHelper } = require('./metric-helper')
+const { MetricHelper, MetricNames } = require('./metric-helper')
const { assertValidCategory } = require('./categories')
const checkErrorResponse = require('./check-error-response')
const coalesceBadge = require('./coalesce-badge')
@@ -214,20 +214,43 @@ class BaseService {
return result
}
- constructor({ sendAndCacheRequest, authHelper }, { handleInternalErrors }) {
+ constructor(
+ { sendAndCacheRequest, authHelper, metricHelper },
+ { handleInternalErrors }
+ ) {
this._requestFetcher = sendAndCacheRequest
this.authHelper = authHelper
this._handleInternalErrors = handleInternalErrors
+ this._metricHelper = metricHelper
}
async _request({ url, options = {}, errorMessages = {} }) {
const logTrace = (...args) => trace.logTrace('fetch', ...args)
logTrace(emojic.bowAndArrow, 'Request', url, '\n', options)
const { res, buffer } = await this._requestFetcher(url, options)
+ await this._meterResponse(res, buffer)
logTrace(emojic.dart, 'Response status code', res.statusCode)
return checkErrorResponse(errorMessages)({ buffer, res })
}
+ static get enabledMetrics() {
+ return []
+ }
+
+ static isMetricEnabled(metricName) {
+ return this.enabledMetrics.includes(metricName)
+ }
+
+ async _meterResponse(res, buffer) {
+ if (
+ this._metricHelper &&
+ this.constructor.isMetricEnabled(MetricNames.SERVICE_RESPONSE_SIZE) &&
+ res.statusCode === 200
+ ) {
+ this._metricHelper.noteServiceResponseSize(buffer.length)
+ }
+ }
+
static _validate(
data,
schema,
@@ -426,6 +449,7 @@ class BaseService {
sendAndCacheRequest: request.asPromise,
sendAndCacheRequestWithCallbacks: request,
githubApiProvider,
+ metricHelper,
},
serviceConfig,
namedParams,
diff --git a/core/base-service/base.spec.js b/core/base-service/base.spec.js
index 11025c6856b2e07640c140d5c385395ec0f42702..06d9cfe0d3f66e4a53ef3d6974fe7777b9faa2f7 100644
--- a/core/base-service/base.spec.js
+++ b/core/base-service/base.spec.js
@@ -4,6 +4,8 @@ const Joi = require('@hapi/joi')
const chai = require('chai')
const { expect } = chai
const sinon = require('sinon')
+const prometheus = require('prom-client')
+const PrometheusMetrics = require('../server/prometheus-metrics')
const trace = require('./trace')
const {
NotFound,
@@ -13,7 +15,7 @@ const {
Deprecated,
} = require('./errors')
const BaseService = require('./base')
-
+const { MetricHelper, MetricNames } = require('./metric-helper')
require('../register-chai-plugins.spec')
chai.use(require('chai-as-promised'))
@@ -65,6 +67,12 @@ class DummyService extends BaseService {
}
}
+class DummyServiceWithServiceResponseSizeMetricEnabled extends DummyService {
+ static get enabledMetrics() {
+ return [MetricNames.SERVICE_RESPONSE_SIZE]
+ }
+}
+
describe('BaseService', function() {
const defaultConfig = { handleInternalErrors: false, private: {} }
@@ -498,6 +506,59 @@ describe('BaseService', function() {
})
})
+ describe('Metrics', function() {
+ let register
+ beforeEach(function() {
+ register = new prometheus.Registry()
+ })
+ const url = 'some-url'
+
+ it('service response size metric is optional', async function() {
+ const metricHelper = MetricHelper.create({
+ metricInstance: new PrometheusMetrics({ register }),
+ ServiceClass: DummyServiceWithServiceResponseSizeMetricEnabled,
+ })
+ const sendAndCacheRequest = async () => ({
+ buffer: 'x'.repeat(65536 + 1),
+ res: { statusCode: 200 },
+ })
+ const serviceInstance = new DummyServiceWithServiceResponseSizeMetricEnabled(
+ { sendAndCacheRequest, metricHelper },
+ defaultConfig
+ )
+
+ await serviceInstance._request({ url })
+
+ expect(register.getSingleMetricAsString('service_response_bytes'))
+ .to.contain(
+ 'service_response_bytes_bucket{le="65536",category="other",family="undefined",service="dummy_service_with_service_response_size_metric_enabled"} 0\n'
+ )
+ .and.to.contain(
+ 'service_response_bytes_bucket{le="131072",category="other",family="undefined",service="dummy_service_with_service_response_size_metric_enabled"} 1\n'
+ )
+ })
+
+ it('service response size metric is disabled by default', async function() {
+ const metricHelper = MetricHelper.create({
+ metricInstance: new PrometheusMetrics({ register }),
+ ServiceClass: DummyService,
+ })
+ const sendAndCacheRequest = async () => ({
+ buffer: 'x',
+ res: { statusCode: 200 },
+ })
+ const serviceInstance = new DummyService(
+ { sendAndCacheRequest, metricHelper },
+ defaultConfig
+ )
+
+ await serviceInstance._request({ url })
+
+ expect(
+ register.getSingleMetricAsString('service_response_bytes')
+ ).to.not.contain('service_response_bytes_bucket')
+ })
+ })
describe('auth', function() {
class AuthService extends DummyService {
static get auth() {
diff --git a/core/base-service/metric-helper.js b/core/base-service/metric-helper.js
index 3e92e7f13668e8580b1e611506d8ab1a8e35a87c..aab44226318fb0498b7cc63d8c576ad6c77bc97f 100644
--- a/core/base-service/metric-helper.js
+++ b/core/base-service/metric-helper.js
@@ -11,9 +11,17 @@ class MetricHelper {
serviceFamily,
name,
})
+ this.serviceResponseSizeHistogram = metricInstance.createServiceResponseSizeHistogram(
+ {
+ category,
+ serviceFamily,
+ name,
+ }
+ )
} else {
this.metricInstance = undefined
this.serviceRequestCounter = undefined
+ this.serviceResponseSizeHistogram = undefined
}
}
@@ -40,6 +48,16 @@ class MetricHelper {
},
}
}
+
+ noteServiceResponseSize(size) {
+ if (this.serviceResponseSizeHistogram) {
+ return this.serviceResponseSizeHistogram.observe(size)
+ }
+ }
}
-module.exports = { MetricHelper }
+const MetricNames = Object.freeze({
+ SERVICE_RESPONSE_SIZE: Symbol('service-response-size'),
+})
+
+module.exports = { MetricHelper, MetricNames }
diff --git a/core/server/prometheus-metrics.js b/core/server/prometheus-metrics.js
index 1c7e276b487bb5e4b25a46e39b97b860c151fb56..bda312a40109ec6a352e828058cb24ddc14fc629 100644
--- a/core/server/prometheus-metrics.js
+++ b/core/server/prometheus-metrics.js
@@ -4,8 +4,8 @@ const decamelize = require('decamelize')
const prometheus = require('prom-client')
module.exports = class PrometheusMetrics {
- constructor() {
- this.register = new prometheus.Registry()
+ constructor({ register } = {}) {
+ this.register = register || new prometheus.Registry()
this.counters = {
numRequests: new prometheus.Counter({
name: 'service_requests_total',
@@ -59,6 +59,14 @@ module.exports = class PrometheusMetrics {
labelNames: ['rate_limit_type'],
registers: [this.register],
}),
+ serviceResponseSize: new prometheus.Histogram({
+ name: 'service_response_bytes',
+ help: 'Service response size in bytes',
+ labelNames: ['category', 'family', 'service'],
+ // buckets: 64KiB, 128KiB, 256KiB, 512KiB, 1MiB, 2MiB, 4MiB, 8MiB
+ buckets: prometheus.exponentialBuckets(64 * 1024, 2, 8),
+ registers: [this.register],
+ }),
}
}
@@ -95,4 +103,13 @@ module.exports = class PrometheusMetrics {
noteRateLimitExceeded(rateLimitType) {
return this.counters.rateLimitExceeded.labels(rateLimitType).inc()
}
+
+ createServiceResponseSizeHistogram({ category, serviceFamily, name }) {
+ const service = decamelize(name)
+ return this.counters.serviceResponseSize.labels(
+ category,
+ serviceFamily,
+ service
+ )
+ }
}
diff --git a/services/dynamic/dynamic-json.service.js b/services/dynamic/dynamic-json.service.js
index 398bd53842376ad0bf43f40c88684f48581d2d46..b9d129cf4a0ba21212e66855ed09e8d80ed779f7 100644
--- a/services/dynamic/dynamic-json.service.js
+++ b/services/dynamic/dynamic-json.service.js
@@ -1,10 +1,15 @@
'use strict'
+const { MetricNames } = require('../../core/base-service/metric-helper')
const { createRoute } = require('./dynamic-helpers')
const jsonPath = require('./json-path')
const { BaseJsonService } = require('..')
module.exports = class DynamicJson extends jsonPath(BaseJsonService) {
+ static get enabledMetrics() {
+ return [MetricNames.SERVICE_RESPONSE_SIZE]
+ }
+
static get route() {
return createRoute('json')
}
diff --git a/services/dynamic/dynamic-xml.service.js b/services/dynamic/dynamic-xml.service.js
index 0182024f693c2b3005d12afb7fe5c3ee3b7780cc..773889be0ec03b286a9ce94265206e0fe19d1181 100644
--- a/services/dynamic/dynamic-xml.service.js
+++ b/services/dynamic/dynamic-xml.service.js
@@ -2,6 +2,7 @@
const { DOMParser } = require('xmldom')
const xpath = require('xpath')
+const { MetricNames } = require('../../core/base-service/metric-helper')
const { renderDynamicBadge, errorMessages } = require('../dynamic-common')
const { createRoute } = require('./dynamic-helpers')
const { BaseService, InvalidResponse, InvalidParameter } = require('..')
@@ -17,6 +18,10 @@ module.exports = class DynamicXml extends BaseService {
return 'dynamic'
}
+ static get enabledMetrics() {
+ return [MetricNames.SERVICE_RESPONSE_SIZE]
+ }
+
static get route() {
return createRoute('xml')
}
diff --git a/services/dynamic/dynamic-yaml.service.js b/services/dynamic/dynamic-yaml.service.js
index 6e0e40eeb9ebbfc597552e72d0c6d8e83a27a51c..66dab8ece6c08f3bb4399e027c0ace72f9e3cfb5 100644
--- a/services/dynamic/dynamic-yaml.service.js
+++ b/services/dynamic/dynamic-yaml.service.js
@@ -1,10 +1,15 @@
'use strict'
+const { MetricNames } = require('../../core/base-service/metric-helper')
const { createRoute } = require('./dynamic-helpers')
const jsonPath = require('./json-path')
const { BaseYamlService } = require('..')
module.exports = class DynamicYaml extends jsonPath(BaseYamlService) {
+ static get enabledMetrics() {
+ return [MetricNames.SERVICE_RESPONSE_SIZE]
+ }
+
static get route() {
return createRoute('yaml')
}