balena-supervisor/sync/device.ts

import * as Docker from 'dockerode';
import { Dockerfile } from 'livepush';
import * as _ from 'lodash';
import { Builder } from 'resin-docker-build';

import { promises as fs } from 'fs';
import { child_process } from 'mz';
import * as Path from 'path';
import { Duplex, Readable } from 'stream';
import * as tar from 'tar-stream';

export function getDocker(deviceAddress: string): Docker {
	return new Docker({
		host: deviceAddress,
		// TODO: Make this configurable
		port: 2375,
	});
}

export async function getSupervisorContainer(
	docker: Docker,
	requireRunning: boolean = false,
): Promise<Docker.ContainerInfo> {
	// First get the supervisor container id
	const containers = await docker.listContainers({
		filters: { name: ['resin_supervisor'] },
		all: !requireRunning,
	});

	if (containers.length !== 1) {
		throw new Error('supervisor container not found');
	}
	return containers[0];
}

export async function getDeviceArch(docker: Docker): Promise<string> {
	try {
		const supervisorContainer = await getSupervisorContainer(docker);
		const arch = supervisorContainer.Labels?.['io.balena.architecture'];
		if (arch == null) {
			// We can try to inspect the image for the
			// architecture if this fails
			const match = /(amd64|i386|aarch64|armv7hf|rpi)/.exec(
				supervisorContainer.Image,
			);
			if (match != null) {
				return match[1];
			}

			throw new Error('supervisor container does not have architecture label');
		}

		return arch.trim();
	} catch (e) {
		throw new Error(
			`Unable to get device architecture: ${e.message}.\nTry specifying the architecture with -a.`,
		);
	}
}

export async function getCacheFrom(docker: Docker): Promise<string[]> {
	const container = await getSupervisorContainer(docker);
	return [container.Image];
}

// perform the build and return the image id
export async function performBuild(
	docker: Docker,
	dockerfile: Dockerfile,
	dockerOpts: { [key: string]: any },
): Promise<void> {
	const builder = Builder.fromDockerode(docker);

	// tar the directory, but replace the dockerfile with the
	// livepush generated one
	const tarStream = await tarDirectory(Path.join(__dirname, '..'), dockerfile);

	return new Promise((resolve, reject) => {
		builder.createBuildStream(dockerOpts, {
			buildSuccess: () => {
				resolve();
			},
			buildFailure: reject,
			buildStream: (stream: Duplex) => {
				stream.pipe(process.stdout);
				tarStream.pipe(stream);
			},
		});
	});
}

async function tarDirectory(
	dir: string,
	dockerfile: Dockerfile,
): Promise<Readable> {
	const pack = tar.pack();

	const add = async (path: string) => {
		const entries = await fs.readdir(path);
		for (const entry of entries) {
			const newPath = Path.resolve(path, entry);
			// Here we filter the things we don't want
			if (
				newPath.includes('node_modules/') ||
				newPath.includes('.git/') ||
				newPath.includes('build/') ||
				newPath.includes('coverage/')
			) {
				continue;
			}
			// We use lstat here, otherwise an error will be
			// thrown on a symbolic link
			const stat = await fs.lstat(newPath);
			if (stat.isDirectory()) {
				await add(newPath);
			} else {
				if (newPath.endsWith('Dockerfile')) {
					pack.entry(
						{ name: 'Dockerfile', mode: stat.mode, size: stat.size },
						dockerfile.generateLiveDockerfile(),
					);
					continue;
				}

				pack.entry(
					{
						name: Path.relative(dir, newPath),
						mode: stat.mode,
						size: stat.size,
					},
					await fs.readFile(newPath),
				);
			}
		}
	};

	await add(dir);
	pack.finalize();
	return pack;
}

// Absolutely no escaping in this function, just be careful
async function runSshCommand(address: string, command: string) {
	// TODO: Make the port configurable
	const [stdout] = await child_process.exec(
		'ssh -p 22222 -o LogLevel=ERROR ' +
			'-o StrictHostKeyChecking=no ' +
			'-o UserKnownHostsFile=/dev/null ' +
			`root@${address} ` +
			`"${command}"`,
	);
	return stdout;
}

export function stopSupervisor(address: string) {
	return runSshCommand(address, 'systemctl stop resin-supervisor');
}

export function startSupervisor(address: string) {
	return runSshCommand(address, 'systemctl start resin-supervisor');
}

export async function replaceSupervisorImage(
	address: string,
	imageName: string,
	imageTag: string,
) {
	// TODO: Maybe don't overwrite the LED file?
	const fileStr = `#This file was edited by livepush
SUPERVISOR_IMAGE=${imageName}
SUPERVISOR_TAG=${imageTag}
LED_FILE=/dev/null
`;

	return runSshCommand(
		address,
		`echo '${fileStr}' > /tmp/update-supervisor.conf`,
	);
}