erlef · iStefo · Apr 25, 2025 · paulo-ferraz-oliveira · Apr 26, 2025 · paulo-ferraz-oliveira
diff --git a/package.json b/package.json
@@ -9,7 +9,7 @@
     "licenses": "yarn licenses generate-disclaimer > 3RD_PARTY_LICENSES",
     "markdownlint": "markdownlint *.md ./github/**/*.md",
     "shellcheck": "shellcheck .github/workflows/*.sh",
-    "test": "node test/setup-beam.test.js",
+    "test": "node --test",
     "yamllint": "yamllint .github/workflows/**.yml && yamllint .*.yml && yamllint *.yml",
     "clean-dist": "rm -rf ./dist",
     "lint": "npm run markdownlint && npm run shellcheck && npm run yamllint && npm run jslint",
@@ -33,4 +33,4 @@
   "engines": {
     "node": ">=20"
   }
-}
+}
diff --git a/src/lib/getRunnerOSVersion.js b/src/lib/getRunnerOSVersion.js
@@ -0,0 +1,85 @@
+const fs = require('node:fs')
+const core = require('@actions/core')
+
+const IMAGE_OS_TO_RUNNER_OS = {
+  ubuntu18: 'ubuntu-18.04',
+  ubuntu20: 'ubuntu-20.04',
+  ubuntu22: 'ubuntu-22.04',
+  ubuntu24: 'ubuntu-24.04',
+  win19: 'windows-2019',
+  win22: 'windows-2022',
+}
+
+function getRunnerOSVersion(imageOS, readFile = fs.readFileSync) {
+  core.startGroup('Get runner OS version')
+
+  core.info(`ImageOS is set to '${imageOS}'`)
+
+  if (imageOS === 'Linux') {
+    core.info('Attempting to detect OS version from /etc/os-release.')
+
+    try {
+      const osRelease = parseOSRelease(readFile)
+      core.debug('Parsed /etc/os-release: ' + JSON.stringify(osRelease))
+
+      const shortVersion = osRelease.VERSION_ID?.split('.')[0]
+      imageOS = osRelease.ID + shortVersion
+
+      core.info(`Detected '${imageOS}'`)
+    } catch (error) {
+      core.error('Failed to parse /etc/os-release: ' + error.message)
+    }
+  }
+
+  const containerFromEnvImageOS = IMAGE_OS_TO_RUNNER_OS[imageOS]
+  if (!containerFromEnvImageOS) {
+    throw new Error(
+      "Tried to map a target OS from env. variable 'ImageOS' (got " +
+        `${imageOS}` +
+        "), but failed. If you're using a " +
+        "self-hosted runner, you should set 'env': 'ImageOS': ... to one of the following: " +
+        "['" +
+        `${Object.keys(IMAGE_OS_TO_RUNNER_OS).join("', '")}` +
+        "']",
+    )
+  }
+
+  core.info('Resulting runner OS: ' + containerFromEnvImageOS)
+
+  core.endGroup()
+
+  return containerFromEnvImageOS
+}
+
+/**
+ * Returns an Object with the contents of `/etc/os-release`, with the keys
+ * being the left side of the '=' and the values being the right side.
+ * The values are stripped of quotes and whitespace.
+ *
+ * Usually, this should result in an object like:
+ *
+ *     {
+ *       ID: 'ubuntu',
+ *       VERSION_ID: '24.04',
+ *       // ...other keys
+ *     }
+ *
+ * @returns {Object} The contents of `/etc/os-release` as an object.
+ */
+function parseOSRelease(readFile) {
+  const osRelease = readFile('/etc/os-release', 'utf8')
+  const lines = osRelease.split('\n')
+
+  return Object.fromEntries(
+    lines
+      .filter((line) => line.includes('='))
+      .map((line) => {
+        const [key, value] = line.split('=')
+        return [key.trim(), value.replace(/"/g, '').trim()]
+      }),
+  )
+}
+
+module.exports = {
+  getRunnerOSVersion,
+}
diff --git a/src/setup-beam.js b/src/setup-beam.js
@@ -6,6 +6,8 @@ const semver = require('semver')
 const fs = require('fs')
 const os = require('os')
 
+const { getRunnerOSVersion } = require('./lib/getRunnerOSVersion')
+
 const MAX_HTTP_RETRIES = 3
 
 main().catch((err) => {
@@ -27,7 +29,7 @@ async function main() {
     versions = parseVersionFile(versionFilePath)
   }
 
-  const osVersion = getRunnerOSVersion()
+  const osVersion = getRunnerOSVersion(process.env.ImageOS)
   const otpSpec = getInput('otp-version', true, 'erlang', versions)
   const elixirSpec = getInput('elixir-version', false, 'elixir', versions)
   const gleamSpec = getInput('gleam-version', false, 'gleam', versions)
@@ -538,31 +540,6 @@ function getRunnerOSArchitecture() {
   )
 }
 
-function getRunnerOSVersion() {
-  const ImageOSToContainer = {
-    ubuntu18: 'ubuntu-18.04',
-    ubuntu20: 'ubuntu-20.04',
-    ubuntu22: 'ubuntu-22.04',
-    ubuntu24: 'ubuntu-24.04',
-    win19: 'windows-2019',
-    win22: 'windows-2022',
-  }
-  const containerFromEnvImageOS = ImageOSToContainer[process.env.ImageOS]
-  if (!containerFromEnvImageOS) {
-    throw new Error(
-      "Tried to map a target OS from env. variable 'ImageOS' (got " +
-        `${process.env.ImageOS}` +
-        "), but failed. If you're using a " +
-        "self-hosted runner, you should set 'env': 'ImageOS': ... to one of the following: " +
-        "['" +
-        `${Object.keys(ImageOSToContainer).join("', '")}` +
-        "']",
-    )
-  }
-
-  return containerFromEnvImageOS
-}
-
 async function getUrlResponse(url, headers, attempt = 1) {
   try {
     const response = await fetch(url, {

diff --git a/test/fixtures/os-release/alpine3.txt b/test/fixtures/os-release/alpine3.txt
@@ -0,0 +1,6 @@
+NAME="Alpine Linux"
+ID=alpine
+VERSION_ID=3.21.3
+PRETTY_NAME="Alpine Linux v3.21"
+HOME_URL="https://alpinelinux.org/"
+BUG_REPORT_URL="https://gitlab.alpinelinux.org/alpine/aports/-/issues"
diff --git a/test/fixtures/os-release/ubuntu22.txt b/test/fixtures/os-release/ubuntu22.txt
@@ -0,0 +1,12 @@
+PRETTY_NAME="Ubuntu 22.04.5 LTS"
+NAME="Ubuntu"
+VERSION_ID="22.04"
+VERSION="22.04.5 LTS (Jammy Jellyfish)"
+VERSION_CODENAME=jammy
+ID=ubuntu
+ID_LIKE=debian
+HOME_URL="https://www.ubuntu.com/"
+SUPPORT_URL="https://help.ubuntu.com/"
+BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/"
+PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy"
+UBUNTU_CODENAME=jammy
diff --git a/test/fixtures/os-release/ubuntu24.txt b/test/fixtures/os-release/ubuntu24.txt
@@ -0,0 +1,13 @@
+PRETTY_NAME="Ubuntu 24.04.2 LTS"
+NAME="Ubuntu"
+VERSION_ID="24.04"
+VERSION="24.04.2 LTS (Noble Numbat)"
+VERSION_CODENAME=noble
+ID=ubuntu
+ID_LIKE=debian
+HOME_URL="https://www.ubuntu.com/"
+SUPPORT_URL="https://help.ubuntu.com/"
+BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/"
+PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy"
+UBUNTU_CODENAME=noble
+LOGO=ubuntu-logo
diff --git a/test/fixtures/os-release/ubuntu25.txt b/test/fixtures/os-release/ubuntu25.txt
@@ -0,0 +1,13 @@
+PRETTY_NAME="Ubuntu 25.04"
+NAME="Ubuntu"
+VERSION_ID="25.04"
+VERSION="25.04 (Plucky Puffin)"
+VERSION_CODENAME=plucky
+ID=ubuntu
+ID_LIKE=debian
+HOME_URL="https://www.ubuntu.com/"
+SUPPORT_URL="https://help.ubuntu.com/"
+BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/"
+PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy"
+UBUNTU_CODENAME=plucky
+LOGO=ubuntu-logo
diff --git a/test/getRunnerOSVersion.test.js b/test/getRunnerOSVersion.test.js
@@ -0,0 +1,97 @@
+const { describe, it, afterEach } = require('node:test')
+const assert = require('node:assert')
+const { readFileSync } = require('node:fs')
+const { join } = require('node:path')
+
+const { getRunnerOSVersion } = require('../src/lib/getRunnerOSVersion')
+
+describe('getRunnerOSVersion', () => {
+  it('throws if no ImageOS env exists', async () => {
+    assert.throws(() => {
+      getRunnerOSVersion(undefined)
+    })
+  })
+
+  describe('simple mappings', () => {
+    for (const [imageOS, runnerOS] of [
+      ['ubuntu18', 'ubuntu-18.04'],
+      ['ubuntu20', 'ubuntu-20.04'],
+      ['ubuntu22', 'ubuntu-22.04'],
+      ['ubuntu24', 'ubuntu-24.04'],
+      ['win19', 'windows-2019'],
+      ['win22', 'windows-2022'],
+    ]) {
+      it(`returns ${runnerOS} for ${imageOS}`, () => {
+        const result = getRunnerOSVersion(imageOS)
+
+        assert.strictEqual(result, runnerOS)
+      })
+    }
+  })
+
+  describe('detect ubuntu version if "ImageOS" is "Linux"', () => {
+    afterEach(() => {
+      // Clear the mock filesystem after each test.
+      for (const path in mockFS) {
+        delete mockFS[path]
+      }
+    })
+
+    it('detects ubuntu 24.04', () => {
+      mockFS['/etc/os-release'] = loadFixture('ubuntu24.txt')
+
+      const result = getRunnerOSVersion('Linux', mockedReadFileSync)
+      assert.strictEqual(result, 'ubuntu-24.04')
+    })
+
+    it('detects ubuntu 22.04', () => {
+      mockFS['/etc/os-release'] = loadFixture('ubuntu22.txt')
+
+      const result = getRunnerOSVersion('Linux', mockedReadFileSync)
+      assert.strictEqual(result, 'ubuntu-22.04')
+    })
+
+    it('rejects ubuntu 25.04 (valid format, but not in availability table)', () => {
+      mockFS['/etc/os-release'] = loadFixture('ubuntu25.txt')
+
+      assert.throws(() => {
+        getRunnerOSVersion('Linux', mockedReadFileSync)
+      })
+    })
+
+    it('rejects alpine 3 (invalid distro)', () => {
+      mockFS['/etc/os-release'] = loadFixture('alpine3.txt')
+
+      assert.throws(() => {
+        getRunnerOSVersion('Linux', mockedReadFileSync)
+      })
+    })
+
+    it('fails with usual message if /etc/os-release is not found', () => {
+      assert.throws(
+        () => {
+          getRunnerOSVersion('Linux', mockedReadFileSync)
+        },
+        {
+          message: /(got Linux)/,
+        },
+      )
+    })
+  })
+})
+
+function loadFixture(filename) {
+  const path = join(__dirname, 'fixtures', 'os-release', filename)
+
+  return readFileSync(path, 'utf8')
+}
+
+const mockFS = {}
+
+function mockedReadFileSync(path) {
+  if (Object.hasOwn(mockFS, path)) {
+    return mockFS[path]
+  }
+
+  throw new Error(`File not found in mockFS: ${path} (forgot to mock it?)`)
+}