feat: Added support for parsing container ids from docker versions us…

…ing cgroups v2. (#1830)

lib/utilization/docker-info.js

@@ -10,6 +10,8 @@ const common = require('./common')
 const NAMES = require('../metrics/names')
 const os = require('os')
 let vendorInfo = null
+const CGROUPS_V1_PATH = '/proc/self/cgroup'
+const CGROUPS_V2_PATH = '/proc/self/mountinfo'
 
 module.exports.getVendorInfo = fetchDockerVendorInfo
 module.exports.clearVendorCache = function clearDockerVendorCache() {
@@ -51,6 +53,12 @@ module.exports.getBootId = function getBootId(agent, callback) {
   }
 }
 
+/**
+ * Attempt to extract container id from either cgroups v1 or v2 file
+ *
+ * @param {object} agent NR instance
+ * @param {Function} callback function to call when done
+ */
 function fetchDockerVendorInfo(agent, callback) {
   if (!agent.config.utilization || !agent.config.utilization.detect_docker) {
     return callback(null, null)
@@ -62,16 +70,56 @@ function fetchDockerVendorInfo(agent, callback) {
 
   if (!os.platform().match(/linux/i)) {
     logger.debug('Platform is not a flavor of linux, omitting docker info')
-    return callback(null)
+    return callback(null, null)
   }
 
-  common.readProc('/proc/self/cgroup', function getCGroup(err, data) {
+  // try v2 path first and if null try parsing v1 path
+  common.readProc(CGROUPS_V2_PATH, function getV2CGroup(err, data) {
+    if (data === null) {
+      logger.debug(
+        `${CGROUPS_V2_PATH} not found, trying to parse container id from ${CGROUPS_V1_PATH}`
+      )
+      findCGroupsV1(callback)
+      return
+    }
+
+    parseCGroupsV2(data, callback)
+  })
+}
+
+/**
+ * Try extracting container id from a /proc/self/mountinfo
+ * e.g. - `528 519 254:1 /docker/containers/84cf3472a20d1bfb4b50e48b6ff50d96dfcd812652d76dd907951e6f98997bce/resolv.conf`
+ *
+ * @param {string} data file contents
+ * @param {Function} callback function to call when done
+ */
+function parseCGroupsV2(data, callback) {
+  const containerLine = new RegExp('/docker/containers/([0-9a-f]{64})/')
+  const line = containerLine.exec(data)
+  if (line) {
+    callback(null, { id: line[1] })
+  } else {
+    logger.debug(`Found ${CGROUPS_V2_PATH} but failed to parse Docker container id.`)
+    callback(null, null)
+  }
+}
+
+/**
+ * Read /proc/self/cgroup and try to extract the container id from a cpu line
+ * e.g. - `4:cpu:/docker/f37a7e4d17017e7bf774656b19ca4360c6cdc4951c86700a464101d0d9ce97ee`
+ *
+ * @param {Function} callback function to call when done
+ */
+function findCGroupsV1(callback) {
+  common.readProc(CGROUPS_V1_PATH, function getCGroup(err, data) {
     if (!data) {
+      logger.debug(`${CGROUPS_V1_PATH} not found, exiting parsing containerId.`)
       return callback(null)
     }
 
     let id = null
-    findCGroups(data, 'cpu', function forEachCpuGroup(cpuGroup) {
+    parseCGroupsV1(data, 'cpu', function forEachCpuGroup(cpuGroup) {
       const match = /(?:^|[^0-9a-f])([0-9a-f]{64})(?:[^0-9a-f]|$)/.exec(cpuGroup)
       if (match) {
         id = match[1]
@@ -91,7 +139,14 @@ function fetchDockerVendorInfo(agent, callback) {
   })
 }
 
-function findCGroups(info, cgroup, eachCb) {
+/**
+ * Iterate line by line to extract the container id from the cpu stanza
+ *
+ * @param {string} info contents of file
+ * @param {string} cgroup value is cpu
+ * @param {Function} eachCb funtion to test if the container id exists
+ */
+function parseCGroupsV1(info, cgroup, eachCb) {
   const target = new RegExp('^\\d+:[^:]*?\\b' + cgroup + '\\b[^:]*:')
   const lines = info.split('\n')
   for (let i = 0; i < lines.length; ++i) {

test/integration/utilization/docker-info.tap.js

@@ -0,0 +1,89 @@
+/*
+ * Copyright 2020 New Relic Corporation. All rights reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+'use strict'
+
+const test = require('tap').test
+const fs = require('fs/promises')
+const common = require('../../../lib/utilization/common')
+const dockerInfo = require('../../../lib/utilization/docker-info')
+const helper = require('../../lib/agent_helper')
+const path = require('path')
+const sinon = require('sinon')
+
+const TEST_DIRECTORY = path.resolve(__dirname, '../../lib/cross_agent_tests/docker_container_id/')
+const TEST_DIRECTORY_V2 = path.resolve(
+  __dirname,
+  '../../lib/cross_agent_tests/docker_container_id_v2/'
+)
+
+const tests = [
+  { name: 'v1', testsDir: TEST_DIRECTORY },
+  { name: 'v2', testsDir: TEST_DIRECTORY_V2 }
+]
+
+tests.forEach(({ name, testsDir }) => {
+  test(`pricing docker info ${name}`, async function (t) {
+    const os = require('os')
+    t.teardown(function () {
+      os.platform.restore()
+    })
+
+    sinon.stub(os, 'platform')
+    os.platform.returns('linux')
+    const data = await fs.readFile(`${testsDir}/cases.json`)
+    const cases = JSON.parse(data)
+
+    cases.forEach((testCase) => {
+      const testFile = path.join(testsDir, testCase.filename)
+      t.test(testCase.filename, makeTest(testCase, testFile, name === 'v2'))
+    })
+    t.end()
+  })
+})
+
+function makeTest(testCase, testFile, v2) {
+  return async function (t) {
+    const agent = helper.loadMockedAgent()
+    sinon.stub(common, 'readProc')
+    const file = await fs.readFile(testFile, { encoding: 'utf8' })
+    mockProcRead(file, v2)
+
+    t.teardown(function () {
+      helper.unloadAgent(agent)
+      dockerInfo.clearVendorCache()
+      common.readProc.restore()
+    })
+
+    await new Promise((resolve) => {
+      dockerInfo.getVendorInfo(agent, function (err, info) {
+        if (testCase.containerId) {
+          t.error(err, 'should not have failed')
+          t.same(info, { id: testCase.containerId }, 'should have expected container id')
+        } else {
+          t.notOk(info, 'should not have found container id')
+        }
+
+        if (testCase.expectedMetrics) {
+          // TODO: No tests currently expect metrics, when one does we'll have to
+          // update this test depending on the format of that.
+          t.bailout('Docker expected metrics found but can not be handled.')
+        } else {
+          t.equal(agent.metrics._metrics.toJSON().length, 0, 'should have no metrics')
+        }
+        resolve()
+      })
+    })
+  }
+}
+
+function mockProcRead(data, v2) {
+  if (!v2) {
+    common.readProc.onCall(0).yields(null, null)
+    common.readProc.onCall(1).yields(null, data)
+  } else {
+    common.readProc.onCall(0).yields(null, data)
+  }
+}

test/lib/cross_agent_tests/docker_container_id_v2/README.md

@@ -0,0 +1,6 @@
+These tests cover parsing of Docker container IDs on Linux hosts out of
+`/proc/self/mountinfo` (or `/proc/<pid>/mountinfo` more generally).
+
+The `cases.json` file lists each filename in this directory containing
+example `/proc/self/mountinfo` content, and the expected Docker container ID that
+should be parsed from that file.

test/lib/cross_agent_tests/docker_container_id_v2/cases.json

@@ -0,0 +1,32 @@
+[
+  {
+    "filename": "docker-20.10.16.txt",
+    "containerId": "84cf3472a20d1bfb4b50e48b6ff50d96dfcd812652d76dd907951e6f98997bce",
+    "expectedMetrics": null
+  },
+  {
+    "filename": "docker-24.0.2.txt",
+    "containerId": "b0a24eed1b031271d8ba0784b8f354b3da892dfd08bbcf14dd7e8a1cf9292f65",
+    "expectedMetrics": null
+  },
+  {
+    "filename": "empty.txt",
+    "containerId": null,
+    "expectedMetrics": null
+  },
+  {
+    "filename": "invalid-characters.txt",
+    "containerId": null,
+    "expectedMetrics": null
+  },
+  {
+    "filename": "docker-too-long.txt",
+    "containerId": null,
+    "expectedMetrics": null
+  },
+  {
+    "filename": "invalid-length.txt",
+    "containerId": null,
+    "expectedMetrics": null 
+  }
+]

test/lib/cross_agent_tests/docker_container_id_v2/docker-20.10.16.txt

@@ -0,0 +1,24 @@
+519 413 0:152 / / rw,relatime master:180 - overlay overlay rw,lowerdir=/var/lib/docker/overlay2/l/YCID3333O5VYPYDNTQRZX4GI67:/var/lib/docker/overlay2/l/G7H4TULAFM2UBFRL7QFQPUNXY5:/var/lib/docker/overlay2/l/RLC4GCL75VGXXXYJJO57STHIYN:/var/lib/docker/overlay2/l/YOZKNWFAP6YX74XEKPHX4KG4UN:/var/lib/docker/overlay2/l/46EQ6YX5PQQZ4Z3WCSMQ6Z4YWI:/var/lib/docker/overlay2/l/KGKX3Z5ZMOCDWOFKBS2FSHMQMQ:/var/lib/docker/overlay2/l/CKFYAF4TXZD4RCE6RG6UNL5WVI,upperdir=/var/lib/docker/overlay2/358c429f7b04ee5a228b94efaebe3413a98fcc676b726f078fe875727e3bddd2/diff,workdir=/var/lib/docker/overlay2/358c429f7b04ee5a228b94efaebe3413a98fcc676b726f078fe875727e3bddd2/work
+520 519 0:155 / /proc rw,nosuid,nodev,noexec,relatime - proc proc rw
+521 519 0:156 / /dev rw,nosuid - tmpfs tmpfs rw,size=65536k,mode=755
+522 521 0:157 / /dev/pts rw,nosuid,noexec,relatime - devpts devpts rw,gid=5,mode=620,ptmxmode=666
+523 519 0:158 / /sys ro,nosuid,nodev,noexec,relatime - sysfs sysfs ro
+524 523 0:30 / /sys/fs/cgroup ro,nosuid,nodev,noexec,relatime - cgroup2 cgroup rw
+525 521 0:154 / /dev/mqueue rw,nosuid,nodev,noexec,relatime - mqueue mqueue rw
+526 521 0:159 / /dev/shm rw,nosuid,nodev,noexec,relatime - tmpfs shm rw,size=65536k
+527 519 254:1 /docker/volumes/3237dea4f8022f1addd7b6f072a9c847eb3e5b8df0d599f462ba7040884d4618/_data /data rw,relatime master:28 - ext4 /dev/vda1 rw
+528 519 254:1 /docker/containers/84cf3472a20d1bfb4b50e48b6ff50d96dfcd812652d76dd907951e6f98997bce/resolv.conf /etc/resolv.conf rw,relatime - ext4 /dev/vda1 rw
+529 519 254:1 /docker/containers/84cf3472a20d1bfb4b50e48b6ff50d96dfcd812652d76dd907951e6f98997bce/hostname /etc/hostname rw,relatime - ext4 /dev/vda1 rw
+530 519 254:1 /docker/containers/84cf3472a20d1bfb4b50e48b6ff50d96dfcd812652d76dd907951e6f98997bce/hosts /etc/hosts rw,relatime - ext4 /dev/vda1 rw
+414 521 0:157 /0 /dev/console rw,nosuid,noexec,relatime - devpts devpts rw,gid=5,mode=620,ptmxmode=666
+415 520 0:155 /bus /proc/bus ro,nosuid,nodev,noexec,relatime - proc proc rw
+416 520 0:155 /fs /proc/fs ro,nosuid,nodev,noexec,relatime - proc proc rw
+417 520 0:155 /irq /proc/irq ro,nosuid,nodev,noexec,relatime - proc proc rw
+418 520 0:155 /sys /proc/sys ro,nosuid,nodev,noexec,relatime - proc proc rw
+419 520 0:155 /sysrq-trigger /proc/sysrq-trigger ro,nosuid,nodev,noexec,relatime - proc proc rw
+420 520 0:160 / /proc/acpi ro,relatime - tmpfs tmpfs ro
+421 520 0:156 /null /proc/kcore rw,nosuid - tmpfs tmpfs rw,size=65536k,mode=755
+422 520 0:156 /null /proc/keys rw,nosuid - tmpfs tmpfs rw,size=65536k,mode=755
+423 520 0:156 /null /proc/timer_list rw,nosuid - tmpfs tmpfs rw,size=65536k,mode=755
+424 520 0:156 /null /proc/sched_debug rw,nosuid - tmpfs tmpfs rw,size=65536k,mode=755
+425 523 0:161 / /sys/firmware ro,relatime - tmpfs tmpfs ro

test/lib/cross_agent_tests/docker_container_id_v2/docker-24.0.2.txt

@@ -0,0 +1,21 @@
+1014 1013 0:269 / /proc rw,nosuid,nodev,noexec,relatime - proc proc rw
+1019 1013 0:270 / /dev rw,nosuid - tmpfs tmpfs rw,size=65536k,mode=755
+1020 1019 0:271 / /dev/pts rw,nosuid,noexec,relatime - devpts devpts rw,gid=5,mode=620,ptmxmode=666
+1021 1013 0:272 / /sys ro,nosuid,nodev,noexec,relatime - sysfs sysfs ro
+1022 1021 0:30 / /sys/fs/cgroup ro,nosuid,nodev,noexec,relatime - cgroup2 cgroup rw
+1023 1019 0:268 / /dev/mqueue rw,nosuid,nodev,noexec,relatime - mqueue mqueue rw
+1024 1019 0:273 / /dev/shm rw,nosuid,nodev,noexec,relatime - tmpfs shm rw,size=65536k
+1025 1013 254:1 /docker/containers/b0a24eed1b031271d8ba0784b8f354b3da892dfd08bbcf14dd7e8a1cf9292f65/resolv.conf /etc/resolv.conf rw,relatime - ext4 /dev/vda1 rw,discard
+1026 1013 254:1 /docker/containers/b0a24eed1b031271d8ba0784b8f354b3da892dfd08bbcf14dd7e8a1cf9292f65/hostname /etc/hostname rw,relatime - ext4 /dev/vda1 rw,discard
+1027 1013 254:1 /docker/containers/b0a24eed1b031271d8ba0784b8f354b3da892dfd08bbcf14dd7e8a1cf9292f65/hosts /etc/hosts rw,relatime - ext4 /dev/vda1 rw,discard
+717 1019 0:271 /0 /dev/console rw,nosuid,noexec,relatime - devpts devpts rw,gid=5,mode=620,ptmxmode=666
+718 1014 0:269 /bus /proc/bus ro,nosuid,nodev,noexec,relatime - proc proc rw
+719 1014 0:269 /fs /proc/fs ro,nosuid,nodev,noexec,relatime - proc proc rw
+720 1014 0:269 /irq /proc/irq ro,nosuid,nodev,noexec,relatime - proc proc rw
+721 1014 0:269 /sys /proc/sys ro,nosuid,nodev,noexec,relatime - proc proc rw
+723 1014 0:269 /sysrq-trigger /proc/sysrq-trigger ro,nosuid,nodev,noexec,relatime - proc proc rw
+726 1014 0:274 / /proc/acpi ro,relatime - tmpfs tmpfs ro
+727 1014 0:270 /null /proc/kcore rw,nosuid - tmpfs tmpfs rw,size=65536k,mode=755
+728 1014 0:270 /null /proc/keys rw,nosuid - tmpfs tmpfs rw,size=65536k,mode=755
+729 1014 0:270 /null /proc/timer_list rw,nosuid - tmpfs tmpfs rw,size=65536k,mode=755
+730 1021 0:275 / /sys/firmware ro,relatime - tmpfs tmpfs ro

test/lib/cross_agent_tests/docker_container_id_v2/docker-too-long.txt

@@ -0,0 +1,21 @@
+1014 1013 0:269 / /proc rw,nosuid,nodev,noexec,relatime - proc proc rw
+1019 1013 0:270 / /dev rw,nosuid - tmpfs tmpfs rw,size=65536k,mode=755
+1020 1019 0:271 / /dev/pts rw,nosuid,noexec,relatime - devpts devpts rw,gid=5,mode=620,ptmxmode=666
+1021 1013 0:272 / /sys ro,nosuid,nodev,noexec,relatime - sysfs sysfs ro
+1022 1021 0:30 / /sys/fs/cgroup ro,nosuid,nodev,noexec,relatime - cgroup2 cgroup rw
+1023 1019 0:268 / /dev/mqueue rw,nosuid,nodev,noexec,relatime - mqueue mqueue rw
+1024 1019 0:273 / /dev/shm rw,nosuid,nodev,noexec,relatime - tmpfs shm rw,size=65536k
+1025 1013 254:1 /docker/containers/3ccfa00432798ff38f85839de1e396f771b4acbe9f4ddea0a761c39b9790a7821/resolv.conf /etc/resolv.conf rw,relatime - ext4 /dev/vda1 rw,discard
+1026 1013 254:1 /docker/containers/3ccfa00432798ff38f85839de1e396f771b4acbe9f4ddea0a761c39b9790a7821/hostname /etc/hostname rw,relatime - ext4 /dev/vda1 rw,discard
+1027 1013 254:1 /docker/containers/3ccfa00432798ff38f85839de1e396f771b4acbe9f4ddea0a761c39b9790a7821/hosts /etc/hosts rw,relatime - ext4 /dev/vda1 rw,discard
+717 1019 0:271 /0 /dev/console rw,nosuid,noexec,relatime - devpts devpts rw,gid=5,mode=620,ptmxmode=666
+718 1014 0:269 /bus /proc/bus ro,nosuid,nodev,noexec,relatime - proc proc rw
+719 1014 0:269 /fs /proc/fs ro,nosuid,nodev,noexec,relatime - proc proc rw
+720 1014 0:269 /irq /proc/irq ro,nosuid,nodev,noexec,relatime - proc proc rw
+721 1014 0:269 /sys /proc/sys ro,nosuid,nodev,noexec,relatime - proc proc rw
+723 1014 0:269 /sysrq-trigger /proc/sysrq-trigger ro,nosuid,nodev,noexec,relatime - proc proc rw
+726 1014 0:274 / /proc/acpi ro,relatime - tmpfs tmpfs ro
+727 1014 0:270 /null /proc/kcore rw,nosuid - tmpfs tmpfs rw,size=65536k,mode=755
+728 1014 0:270 /null /proc/keys rw,nosuid - tmpfs tmpfs rw,size=65536k,mode=755
+729 1014 0:270 /null /proc/timer_list rw,nosuid - tmpfs tmpfs rw,size=65536k,mode=755
+730 1021 0:275 / /sys/firmware ro,relatime - tmpfs tmpfs ro