support standalone mode and display version

Signed-off-by: CrazyMax <crazy-max@users.noreply.github.com>

README.md

@@ -24,6 +24,7 @@ ___
   * [BuildKit daemon configuration](#buildkit-daemon-configuration)
     * [Registry mirror](#registry-mirror)
     * [Max parallelism](#max-parallelism)
+  * [Standalone mode](#standalone-mode)
 * [Customizing](#customizing)
   * [inputs](#inputs)
   * [outputs](#outputs)
@@ -180,6 +181,33 @@ jobs:
           config: .github/buildkitd.toml
 ```
 
+### Standalone mode
+
+If you don't have the Docker CLI installed on the GitHub Runner, buildx binary
+is invoked directly, instead of calling it as a docker plugin. This can be
+useful if you want to use the `kubernetes` driver in your self-hosted runner:
+
+```yaml
+name: ci
+
+on:
+  push:
+
+jobs:
+  buildx:
+    runs-on: ubuntu-latest
+    steps:
+      -
+        name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v1
+        with:
+          driver: kubernetes
+      -
+        name: Build
+        run: |
+          buildx build .
+```
+
 ## Customizing
 
 ### inputs
@@ -195,10 +223,10 @@ Following inputs can be used as `step.with` keys
 | `install`          | Bool    | Sets up `docker build` command as an alias to `docker buildx` (default `false`) |
 | `use`              | Bool    | Switch to this builder instance (default `true`) |
 | `endpoint`         | String  | [Optional address for docker socket](https://github.com/docker/buildx/blob/master/docs/reference/buildx_create.md#description) or context from `docker context ls` |
-| `config`           | String  | [BuildKit config file](https://github.com/docker/buildx/blob/master/docs/reference/buildx_create.md#config) |
-| `config-inline`    | String  | Same as `config` but inline |
+| `config`¹          | String  | [BuildKit config file](https://github.com/docker/buildx/blob/master/docs/reference/buildx_create.md#config) |
+| `config-inline`¹   | String  | Same as `config` but inline |
 
-> `config` and `config-inline` are mutually exclusive.
+> * ¹ `config` and `config-inline` are mutually exclusive
 
 > `CSV` type must be a newline-delimited string
 > ```yaml

__tests__/buildx.test.ts

@@ -32,6 +32,17 @@ describe('isAvailable', () => {
   });
 });
 
+describe('isAvailable standalone', () => {
+  const execSpy = jest.spyOn(exec, 'getExecOutput');
+  buildx.isAvailable(true);
+
+  // eslint-disable-next-line jest/no-standalone-expect
+  expect(execSpy).toHaveBeenCalledWith(`buildx`, [], {
+    silent: true,
+    ignoreReturnCode: true
+  });
+});
+
 describe('getVersion', () => {
   it('valid', async () => {
     const version = await buildx.getVersion();
@@ -75,29 +86,32 @@ describe('build', () => {
 
   // eslint-disable-next-line jest/no-disabled-tests
   it.skip('builds refs/pull/648/head', async () => {
-    const buildxBin = await buildx.build('https://github.com/docker/buildx.git#refs/pull/648/head', tmpDir);
+    const buildxBin = await buildx.build('https://github.com/docker/buildx.git#refs/pull/648/head', tmpDir, false);
     expect(fs.existsSync(buildxBin)).toBe(true);
   }, 100000);
 
   // eslint-disable-next-line jest/no-disabled-tests
   it.skip('builds 67bd6f4dc82a9cd96f34133dab3f6f7af803bb14', async () => {
-    const buildxBin = await buildx.build('https://github.com/docker/buildx.git#67bd6f4dc82a9cd96f34133dab3f6f7af803bb14', tmpDir);
+    const buildxBin = await buildx.build('https://github.com/docker/buildx.git#67bd6f4dc82a9cd96f34133dab3f6f7af803bb14', tmpDir, false);
     expect(fs.existsSync(buildxBin)).toBe(true);
   }, 100000);
 });
 
 describe('install', () => {
   const tmpDir = fs.mkdtempSync(path.join(os.tmpdir(), 'setup-buildx-'));
-
-  it('acquires v0.4.1 version of buildx', async () => {
-    const buildxBin = await buildx.install('v0.4.1', tmpDir);
+  test.each([
+    ['v0.4.1', false],
+    ['latest', false],
+    ['v0.4.1', true],
+    ['latest', true]
+  ])(
+    'acquires %p of buildx (standalone: %p)',
+    async (version, standalone) => {
+      const buildxBin = await buildx.install(version, tmpDir, standalone);
       expect(fs.existsSync(buildxBin)).toBe(true);
-  }, 100000);
-
-  it('acquires latest version of buildx', async () => {
-    const buildxBin = await buildx.install('latest', tmpDir);
-    expect(fs.existsSync(buildxBin)).toBe(true);
-  }, 100000);
+    },
+    100000
+  );
 });
 
 describe('getConfig', () => {

__tests__/docker.test.ts

@@ -0,0 +1,16 @@
+import {describe, expect, it, jest} from '@jest/globals';
+import * as docker from '../src/docker';
+import * as exec from '@actions/exec';
+
+describe('isAvailable', () => {
+  it('cli', () => {
+    const execSpy = jest.spyOn(exec, 'getExecOutput');
+    docker.isAvailable();
+
+    // eslint-disable-next-line jest/no-standalone-expect
+    expect(execSpy).toHaveBeenCalledWith(`docker`, undefined, {
+      silent: true,
+      ignoreReturnCode: true
+    });
+  });
+});

src/buildx.ts

@@ -41,9 +41,10 @@ export async function getConfig(s: string, file: boolean): Promise<string> {
   return configFile;
 }
 
-export async function isAvailable(): Promise<boolean> {
+export async function isAvailable(standalone?: boolean): Promise<boolean> {
+  const cmd = getCommand([], standalone);
   return await exec
-    .getExecOutput('docker', ['buildx'], {
+    .getExecOutput(cmd.commandLine, cmd.args, {
       ignoreReturnCode: true,
       silent: true
     })
@@ -52,12 +53,17 @@ export async function isAvailable(): Promise<boolean> {
         return false;
       }
       return res.exitCode == 0;
+    })
+    // eslint-disable-next-line @typescript-eslint/no-unused-vars
+    .catch(error => {
+      return false;
     });
 }
 
-export async function getVersion(): Promise<string> {
+export async function getVersion(standalone?: boolean): Promise<string> {
+  const cmd = getCommand(['version'], standalone);
   return await exec
-    .getExecOutput('docker', ['buildx', 'version'], {
+    .getExecOutput(cmd.commandLine, cmd.args, {
       ignoreReturnCode: true,
       silent: true
     })
@@ -81,9 +87,10 @@ export function satisfies(version: string, range: string): boolean {
   return semver.satisfies(version, range) || /^[0-9a-f]{7}$/.exec(version) !== null;
 }
 
-export async function inspect(name: string): Promise<Builder> {
+export async function inspect(name: string, standalone?: boolean): Promise<Builder> {
+  const cmd = getCommand(['inspect', name], standalone);
   return await exec
-    .getExecOutput(`docker`, ['buildx', 'inspect', name], {
+    .getExecOutput(cmd.commandLine, cmd.args, {
       ignoreReturnCode: true,
       silent: true
     })
@@ -133,7 +140,7 @@ export async function inspect(name: string): Promise<Builder> {
     });
 }
 
-export async function build(inputBuildRef: string, dockerConfigHome: string): Promise<string> {
+export async function build(inputBuildRef: string, dest: string, standalone: boolean): Promise<string> {
   // eslint-disable-next-line prefer-const
   let [repo, ref] = inputBuildRef.split('#');
   if (ref.length == 0) {
@@ -152,8 +159,27 @@ export async function build(inputBuildRef: string, dockerConfigHome: string): Pr
   toolPath = tc.find('buildx', vspec);
   if (!toolPath) {
     const outFolder = path.join(context.tmpDir(), 'out').split(path.sep).join(path.posix.sep);
+    let buildWithStandalone = false;
+    const standaloneFound = await isAvailable(true);
+    const pluginFound = await isAvailable(false);
+    if (standalone && standaloneFound) {
+      core.debug(`Buildx standalone found, build with it`);
+      buildWithStandalone = true;
+    } else if (!standalone && pluginFound) {
+      core.debug(`Buildx plugin found, build with it`);
+      buildWithStandalone = false;
+    } else if (standaloneFound) {
+      core.debug(`Buildx plugin not found, but standalone found so trying to build with it`);
+      buildWithStandalone = true;
+    } else if (pluginFound) {
+      core.debug(`Buildx standalone not found, but plugin found so trying to build with it`);
+      buildWithStandalone = false;
+    } else {
+      throw new Error(`Neither buildx standalone or plugin have been found to build from ref`);
+    }
+    const buildCmd = getCommand(['build', '--target', 'binaries', '--build-arg', 'BUILDKIT_CONTEXT_KEEP_GIT_DIR=1', '--output', `type=local,dest=${outFolder}`, inputBuildRef], buildWithStandalone);
     toolPath = await exec
-      .getExecOutput('docker', ['buildx', 'build', '--target', 'binaries', '--build-arg', 'BUILDKIT_CONTEXT_KEEP_GIT_DIR=1', '--output', `type=local,dest=${outFolder}`, inputBuildRef], {
+      .getExecOutput(buildCmd.commandLine, buildCmd.args, {
         ignoreReturnCode: true
       })
       .then(res => {
@@ -164,10 +190,13 @@ export async function build(inputBuildRef: string, dockerConfigHome: string): Pr
       });
   }
 
-  return setPlugin(toolPath, dockerConfigHome);
+  if (standalone) {
+    return setStandalone(toolPath, dest);
+  }
+  return setPlugin(toolPath, dest);
 }
 
-export async function install(inputVersion: string, dockerConfigHome: string): Promise<string> {
+export async function install(inputVersion: string, dest: string, standalone: boolean): Promise<string> {
   const release: github.GitHubRelease | null = await github.getRelease(inputVersion);
   if (!release) {
     throw new Error(`Cannot find buildx ${inputVersion} release`);
@@ -185,10 +214,40 @@ export async function install(inputVersion: string, dockerConfigHome: string): P
     toolPath = await download(version);
   }
 
-  return setPlugin(toolPath, dockerConfigHome);
+  if (standalone) {
+    return setStandalone(toolPath, dest);
+  }
+  return setPlugin(toolPath, dest);
+}
+
+async function setStandalone(toolPath: string, dest: string): Promise<string> {
+  core.info('Standalone mode');
+  const toolBinPath = path.join(toolPath, context.osPlat == 'win32' ? 'docker-buildx.exe' : 'docker-buildx');
+
+  const binDir = path.join(dest, 'bin');
+  core.debug(`Bin dir is ${binDir}`);
+  if (!fs.existsSync(binDir)) {
+    fs.mkdirSync(binDir, {recursive: true});
+  }
+
+  const filename: string = context.osPlat == 'win32' ? 'buildx.exe' : 'buildx';
+  const buildxPath: string = path.join(binDir, filename);
+  core.debug(`Bin path is ${buildxPath}`);
+  fs.copyFileSync(toolBinPath, buildxPath);
+
+  core.info('Fixing perms');
+  fs.chmodSync(buildxPath, '0755');
+
+  core.addPath(binDir);
+  core.info('Added buildx to the path');
+
+  return buildxPath;
 }
 
 async function setPlugin(toolPath: string, dockerConfigHome: string): Promise<string> {
+  core.info('Docker plugin mode');
+  const toolBinPath = path.join(toolPath, context.osPlat == 'win32' ? 'docker-buildx.exe' : 'docker-buildx');
+
   const pluginsDir: string = path.join(dockerConfigHome, 'cli-plugins');
   core.debug(`Plugins dir is ${pluginsDir}`);
   if (!fs.existsSync(pluginsDir)) {
@@ -198,7 +257,7 @@ async function setPlugin(toolPath: string, dockerConfigHome: string): Promise<st
   const filename: string = context.osPlat == 'win32' ? 'docker-buildx.exe' : 'docker-buildx';
   const pluginPath: string = path.join(pluginsDir, filename);
   core.debug(`Plugin path is ${pluginPath}`);
-  fs.copyFileSync(path.join(toolPath, filename), pluginPath);
+  fs.copyFileSync(toolBinPath, pluginPath);
 
   core.info('Fixing perms');
   fs.chmodSync(pluginPath, '0755');
@@ -269,3 +328,10 @@ export async function getBuildKitVersion(containerID: string): Promise<string> {
       return bkitimage.stdout.trim();
     });
 }
+
+export function getCommand(args: Array<string>, standalone?: boolean) {
+  return {
+    commandLine: standalone ? 'buildx' : 'docker',
+    args: standalone ? args : ['buildx', ...args]
+  };
+}

src/docker.ts

@@ -0,0 +1,19 @@
+import * as exec from '@actions/exec';
+
+export async function isAvailable(): Promise<boolean> {
+  return await exec
+    .getExecOutput('docker', undefined, {
+      ignoreReturnCode: true,
+      silent: true
+    })
+    .then(res => {
+      if (res.stderr.length > 0 && res.exitCode != 0) {
+        return false;
+      }
+      return res.exitCode == 0;
+    })
+    // eslint-disable-next-line @typescript-eslint/no-unused-vars
+    .catch(error => {
+      return false;
+    });
+}

src/main.ts

@@ -3,6 +3,7 @@ import * as path from 'path';
 import * as uuid from 'uuid';
 import * as buildx from './buildx';
 import * as context from './context';
+import * as docker from './docker';
 import * as stateHelper from './state-helper';
 import * as util from './util';
 import * as core from '@actions/core';
@@ -10,32 +11,54 @@ import * as exec from '@actions/exec';
 
 async function run(): Promise<void> {
   try {
-    core.startGroup(`Docker info`);
-    await exec.exec('docker', ['version']);
-    await exec.exec('docker', ['info']);
-    core.endGroup();
-
     const inputs: context.Inputs = await context.getInputs();
     const dockerConfigHome: string = process.env.DOCKER_CONFIG || path.join(os.homedir(), '.docker');
 
-    if (util.isValidUrl(inputs.version)) {
-      core.startGroup(`Build and install buildx`);
-      await buildx.build(inputs.version, dockerConfigHome);
+    // standalone if docker cli not available
+    const standalone = !(await docker.isAvailable());
+    stateHelper.setStandalone(standalone);
+
+    core.startGroup(`Docker info`);
+    if (standalone) {
+      core.info(`Docker info skipped in standalone mode`);
+    } else {
+      await exec.exec('docker', ['version'], {
+        failOnStdErr: false
+      });
+      await exec.exec('docker', ['info'], {
+        failOnStdErr: false
+      });
+    }
     core.endGroup();
-    } else if (!(await buildx.isAvailable()) || inputs.version) {
+
+    if (util.isValidUrl(inputs.version)) {
+      if (standalone) {
+        throw new Error(`Cannot build from source without the Docker CLI`);
+      }
+      core.startGroup(`Build and install buildx`);
+      await buildx.build(inputs.version, dockerConfigHome, standalone);
+      core.endGroup();
+    } else if (!(await buildx.isAvailable(standalone)) || inputs.version) {
       core.startGroup(`Download and install buildx`);
-      await buildx.install(inputs.version || 'latest', dockerConfigHome);
+      await buildx.install(inputs.version || 'latest', standalone ? context.tmpDir() : dockerConfigHome, standalone);
       core.endGroup();
     }
 
-    const buildxVersion = await buildx.getVersion();
+    const buildxVersion = await buildx.getVersion(standalone);
+    await core.group(`Buildx version`, async () => {
+      const versionCmd = buildx.getCommand(['version'], standalone);
+      await exec.exec(versionCmd.commandLine, versionCmd.args, {
+        failOnStdErr: false
+      });
+    });
+
     const builderName: string = inputs.driver == 'docker' ? 'default' : `builder-${uuid.v4()}`;
     context.setOutput('name', builderName);
     stateHelper.setBuilderName(builderName);
 
     if (inputs.driver !== 'docker') {
       core.startGroup(`Creating a new builder instance`);
-      const createArgs: Array<string> = ['buildx', 'create', '--name', builderName, '--driver', inputs.driver];
+      const createArgs: Array<string> = ['create', '--name', builderName, '--driver', inputs.driver];
       if (buildx.satisfies(buildxVersion, '>=0.3.0')) {
         await context.asyncForEach(inputs.driverOpts, async driverOpt => {
           createArgs.push('--driver-opt', driverOpt);
@@ -55,26 +78,31 @@ async function run(): Promise<void> {
       } else if (inputs.configInline) {
         createArgs.push('--config', await buildx.getConfigInline(inputs.configInline));
       }
-      await exec.exec('docker', createArgs);
+      const createCmd = buildx.getCommand(createArgs, standalone);
+      await exec.exec(createCmd.commandLine, createCmd.args);
       core.endGroup();
 
       core.startGroup(`Booting builder`);
-      const bootstrapArgs: Array<string> = ['buildx', 'inspect', '--bootstrap'];
+      const bootstrapArgs: Array<string> = ['inspect', '--bootstrap'];
       if (buildx.satisfies(buildxVersion, '>=0.4.0')) {
         bootstrapArgs.push('--builder', builderName);
       }
-      await exec.exec('docker', bootstrapArgs);
+      const bootstrapCmd = buildx.getCommand(bootstrapArgs, standalone);
+      await exec.exec(bootstrapCmd.commandLine, bootstrapCmd.args);
       core.endGroup();
     }
 
     if (inputs.install) {
+      if (standalone) {
+        throw new Error(`Cannot set buildx as default builder without the Docker CLI`);
+      }
       core.startGroup(`Setting buildx as default builder`);
       await exec.exec('docker', ['buildx', 'install']);
       core.endGroup();
     }
 
     core.startGroup(`Inspect builder`);
-    const builder = await buildx.inspect(builderName);
+    const builder = await buildx.inspect(builderName, standalone);
     core.info(JSON.stringify(builder, undefined, 2));
     context.setOutput('driver', builder.driver);
     context.setOutput('endpoint', builder.node_endpoint);
@@ -83,7 +111,7 @@ async function run(): Promise<void> {
     context.setOutput('platforms', builder.node_platforms);
     core.endGroup();
 
-    if (inputs.driver == 'docker-container') {
+    if (!standalone && inputs.driver == 'docker-container') {
       stateHelper.setContainerName(`buildx_buildkit_${builder.node_name}`);
       core.startGroup(`BuildKit version`);
       core.info(await buildx.getBuildKitVersion(`buildx_buildkit_${builder.node_name}`));
@@ -114,8 +142,9 @@ async function cleanup(): Promise<void> {
 
   if (stateHelper.builderName.length > 0) {
     core.startGroup(`Removing builder`);
+    const rmCmd = buildx.getCommand(['rm', stateHelper.builderName], /true/i.test(stateHelper.standalone));
     await exec
-      .getExecOutput('docker', ['buildx', 'rm', `${stateHelper.builderName}`], {
+      .getExecOutput(rmCmd.commandLine, rmCmd.args, {
         ignoreReturnCode: true
       })
       .then(res => {

src/state-helper.ts

@@ -2,6 +2,7 @@ import * as core from '@actions/core';
 
 export const IsPost = !!process.env['STATE_isPost'];
 export const IsDebug = !!process.env['STATE_isDebug'];
+export const standalone = process.env['STATE_standalone'] || '';
 export const builderName = process.env['STATE_builderName'] || '';
 export const containerName = process.env['STATE_containerName'] || '';
 
@@ -9,6 +10,10 @@ export function setDebug(debug: string) {
   core.saveState('isDebug', debug);
 }
 
+export function setStandalone(standalone: boolean) {
+  core.saveState('standalone', standalone);
+}
+
 export function setBuilderName(builderName: string) {
   core.saveState('builderName', builderName);
 }