Created src folder and moved code to this folder

Dockerfile

@@ -1,4 +1,4 @@
-FROM node:18-alpine
+FROM --platform=linux/amd64 node:18-alpine
 
 RUN mkdir -p /usr/src/app && \
     chown -R node:node /usr/src/app
@@ -10,4 +10,4 @@ RUN npm install
 
 COPY . /usr/src/app
 
-CMD ["node", "index.js"]
+CMD ["node", "src/index.js"]

build/build-release.sh

@@ -37,7 +37,7 @@ fullImageName="${imageName}:${releaseTag}"
 pushd release/${releaseTag}
     tar xvzf release.tgz
     pushd pushgateway-pruner-${releaseTag}
-    docker build -t ${fullImageName} .
+    docker build --platform=linux/amd64 -t ${fullImageName} .
 popd
 
 echo "======================================================================="

package.json

@@ -25,10 +25,10 @@
     "node": ">=18.0.0"
   },
   "scripts": {
-    "test": "jest"
+    "test": "jest --runInBand"
   },
   "dependencies": {
-    "axios": "1.5.1",
+    "axios": "1.6.1",
     "prom-client": "15.0.0",
     "winston": "3.11.0"
   },

index.js → src/functions.js

@@ -1,38 +1,28 @@
-'use strict'
-
 const axios = require('axios')
 const logger = require('./logger')
 
-let PUSHGATEWAY_URL = resolve('PUSHGATEWAY_URL', 'http://localhost:9091')
-if (!PUSHGATEWAY_URL.endsWith('/'))
-    PUSHGATEWAY_URL += '/'
-logger.info(`Pushgateway URL: ${PUSHGATEWAY_URL}`)
-
-const INTERVAL_SECONDS = resolve('PRUNE_INTERVAL', 60)
-const PRUNE_THRESHOLD_SECONDS = resolve('PRUNE_THRESHOLD', 600)
-logger.info(`Prune interval: ${INTERVAL_SECONDS} seconds.`)
-logger.info(`Prune threshold: ${PRUNE_THRESHOLD_SECONDS} seconds.`)
+const METRIC_NAME = 'push_time_seconds';
 
-async function pruneGroups() {
+async function pruneGroups(pushgatewayUrl, pruneThresholdSeconds) {
     logger.info('Starting prune process...');
 
     // Get metrics request from Prometheus push gateway
     let metrics = null;
     try {
-        metrics = await getMetrics(PUSHGATEWAY_URL);
+        metrics = await getMetrics(pushgatewayUrl);
     } catch (e) {
-        throw new Error(`GET /metrics from ${PUSHGATEWAY_URL} failed. Cause: ${e}`)
+        throw new Error(`GET /metrics from ${pushgatewayUrl} failed. Cause: ${e}`)
     }
 
     // Get 'push_time_seconds' groups and filter the ones that are above pruneThresholdSeconds
     const groupings = parseGroupings(metrics)
-    const filteredGroupings = filterOldGroupings(groupings)
+    const filteredGroupings = filterOldGroupings(groupings, pruneThresholdSeconds)
     logger.info(`Found ${groupings.length} grouping(s), of which ${filteredGroupings.length} will be pruned`)
 
     if (filteredGroupings.length > 0) {
         filteredGroupings.map((filteredGroup) => {
                 try {
-                    deleteGrouping(filteredGroup)
+                    deleteGrouping(filteredGroup, pushgatewayUrl)
                 } catch (e) {
                     logger.error(`Pruning group ${filteredGroup} failed.`)
                 }
@@ -57,9 +47,9 @@ function resolve(envVar, defaultValue) {
     return defaultValue
 }
 
-async function getMetrics() {
+async function getMetrics(pushgatewayUrl) {
     logger.debug('getMetrics()')
-    const getMetricsResponse = await axios.get(PUSHGATEWAY_URL + 'metrics', {
+    const getMetricsResponse = await axios.get(pushgatewayUrl + 'metrics', {
         timeout: 2000
     });
 
@@ -81,7 +71,7 @@ function parseGroupings(metrics) {
     const pushGroups = []
     for (let i = 0; i < lines.length; ++i) {
         const line = lines[i]
-        if (line.startsWith("push_time_seconds")) {
+        if (line.startsWith(METRIC_NAME)) {
             const labels = parseLabels(line.substring(line.indexOf('{') + 1, line.indexOf('}')))
             const timestamp = new Date(parseFloat(line.substring(line.indexOf('}') + 1).trim()) * 1000)
             pushGroups.push({
@@ -113,12 +103,12 @@ function parseLabels(labels) {
     return labelMap
 }
 
-function filterOldGroupings(groupings) {
+function filterOldGroupings(groupings, pruneThresholdSeconds) {
     logger.debug('filterOldGroupings()');
     const filteredGroupings = []
     const now = new Date()
     for (let i = 0; i < groupings.length; ++i) {
-        if ((now - groupings[i].timestamp) > PRUNE_THRESHOLD_SECONDS * 1000) {
+        if ((now - groupings[i].timestamp) > pruneThresholdSeconds * 1000) {
             filteredGroupings.push(groupings[i])
         }
     }
@@ -127,7 +117,7 @@ function filterOldGroupings(groupings) {
     return filteredGroupings
 }
 
-async function deleteGrouping(grouping) {
+async function deleteGrouping(grouping, pushgatewayUrl) {
     logger.debug('deleteGrouping()', grouping)
 
     const job = grouping.labels.job
@@ -141,7 +131,7 @@ async function deleteGrouping(grouping) {
         return;
     }
 
-    const url = PUSHGATEWAY_URL + encodeURIComponent(`metrics/job/${job}/${labelName}/${labelValue}`)
+    const url = pushgatewayUrl + encodeURIComponent(`metrics/job/${job}/${labelName}/${labelValue}`)
     logger.debug(`Delete URL: ${url}`)
     const deleteResponse = await axios.delete(url, {
         timeout: 2000
@@ -159,7 +149,6 @@ async function deleteGrouping(grouping) {
 
     logger.debug(`DELETE ${url} succeeded, status code ${deleteResponse.status}`)
     logger.info('Deleted grouping', grouping.labels)
-    return;
 }
 
 function findLabelName(labels) {
@@ -171,9 +160,8 @@ function findLabelName(labels) {
     return null
 }
 
-const interval = setInterval(pruneGroups, INTERVAL_SECONDS * 1000)
-
 module.exports = {
+    resolve,
     pruneGroups,
-    interval
+    parseLabels
 }

src/index.js

@@ -0,0 +1,22 @@
+const { resolve, pruneGroups } = require('./functions')
+const logger = require('./logger')
+
+let PUSHGATEWAY_URL = resolve('PUSHGATEWAY_URL', 'http://localhost:9091')
+if (!PUSHGATEWAY_URL.endsWith('/'))
+    PUSHGATEWAY_URL += '/'
+logger.info(`Pushgateway URL: ${PUSHGATEWAY_URL}`)
+
+const INTERVAL_SECONDS = resolve('PRUNE_INTERVAL', 60)
+const PRUNE_THRESHOLD_SECONDS = resolve('PRUNE_THRESHOLD', 600)
+logger.info(`Prune interval: ${INTERVAL_SECONDS} seconds.`)
+logger.info(`Prune threshold: ${PRUNE_THRESHOLD_SECONDS} seconds.`)
+
+const interval = setInterval(
+    () => pruneGroups(PUSHGATEWAY_URL, PRUNE_THRESHOLD_SECONDS),
+    INTERVAL_SECONDS * 1000
+)
+
+module.exports = {
+    pruneGroups,
+    interval
+}

logger.js → src/logger.js

@@ -1,6 +1,6 @@
 const winston = require('winston')
 
-let logLevel = process.env.DEBUG == 'true' ? 'debug' : 'info'
+let logLevel = process.env.DEBUG === 'true' ? 'debug' : 'info'
 
 const logger = winston.createLogger({
     transports: [

test/functions.test.js

@@ -0,0 +1,82 @@
+const { resolve, parseLabels } = require('./../src/functions')
+
+function mockProcessEnv(envVar, envValue) {
+    process.env[envVar] = envValue;
+}
+
+describe('Functions test', () => {
+    describe('Resolve function test', () => {
+        const envVar = 'TEST_ENV_VAR';
+        const defaultValue = 'default_value';
+        const defaultProcessEnvValues = { ...process.env };
+
+        beforeEach(() => {
+            jest.resetModules();
+            process.env = { ...defaultProcessEnvValues };
+        });
+
+        afterAll(() => {
+            process.env = defaultProcessEnvValues; // Restore old environment
+        });
+
+        test('Return process env value string when specified', () => {
+            const expectedValue = 'expected_value';
+            mockProcessEnv(envVar, expectedValue);
+
+            const responseValue = resolve(envVar, defaultValue);
+
+            expect(responseValue).toBe(expectedValue);
+        });
+
+        test('Return process env value integer when specified', () => {
+            const expectedValue = 123;
+            mockProcessEnv(envVar, expectedValue);
+
+            const responseValue = resolve(envVar, defaultValue);
+
+            expect(responseValue).toBe(expectedValue);
+        });
+
+        test('Return default process env value when no specified', () => {
+            const responseValue = resolve(envVar, defaultValue);
+
+            expect(responseValue).toBe(defaultValue);
+        });
+    });
+
+    describe('Parse labels function test', () => {
+        test('Return the specific labels', () => {
+            const stringLabels = 'instance="instance_1",job="application_1"';
+            const expectedValue = {
+                instance: 'instance_1',
+                job: 'application_1'
+            };
+
+            const responseValue = parseLabels(stringLabels);
+
+            expect(responseValue).toEqual(expectedValue);
+        });
+
+        test('Return empty string in labels that does not have a value', () => {
+            const stringLabels = 'instance="",job="application_1"';
+            const expectedValue = {
+                instance: '',
+                job: 'application_1'
+            };
+
+            const responseValue = parseLabels(stringLabels);
+
+            expect(responseValue).toEqual(expectedValue);
+        });
+
+        test('Return empty if no labels', () => {
+            const stringLabels = '';
+            const expectedValue = {};
+
+            const responseValue = parseLabels(stringLabels);
+
+            expect(responseValue).toEqual(expectedValue);
+        });
+    });
+})
+

test/index.test.js

@@ -1,5 +1,5 @@
 const axios = require('axios')
-const { pruneGroups, interval } = require('./../index')
+const { pruneGroups, interval } = require('./../src/index')
 
 jest.mock('axios');
 
@@ -39,6 +39,10 @@ describe('PushGateway Pruner', () => {
         mockDeleteMetricsResponse();
     });
 
+    beforeEach(() => {
+        expect(axios.delete).toHaveBeenCalledTimes(0);
+    })
+
     afterEach(() => {
         jest.useRealTimers();