feat: configure support for generic integrations

Co-authored-by: Gage Orsburn <gageorsburn@live.com>

app/components/Header.tsx

@@ -9,7 +9,11 @@ import Menu from './Menu'
 import TabLink from './TabLink'
 
 interface Properties {
-	readonly data?: HeadplaneContext & { user?: SessionData['user'] }
+	readonly data?: {
+		acl: HeadplaneContext['acl']
+		config: HeadplaneContext['config']
+		user?: SessionData['user']
+	}
 }
 
 interface LinkProperties {

app/components/Link.tsx

@@ -2,30 +2,29 @@ import { LinkExternalIcon } from '@primer/octicons-react'
 
 import { cn } from '~/utils/cn'
 
-/* eslint-disable unicorn/no-keyword-prefix */
-type Properties = {
-	readonly to: string;
-	readonly name: string;
-	readonly children: string;
-	readonly className?: string;
+interface Props {
+	to: string
+	name: string
+	children: string
+	className?: string
 }
 
-export default function Link({ to, name: alt, children, className }: Properties) {
+export default function Link({ to, name: alt, children, className }: Props) {
 	return (
 		<a
 			href={to}
 			aria-label={alt}
-			target='_blank'
-			rel='noreferrer'
+			target="_blank"
+			rel="noreferrer"
 			className={cn(
 				'inline-flex items-center gap-x-1',
 				'text-blue-500 hover:text-blue-700',
 				'dark:text-blue-400 dark:hover:text-blue-300',
-				className
+				className,
 			)}
 		>
 			{children}
-			<LinkExternalIcon className='h-3 w-3'/>
+			<LinkExternalIcon className="h-3 w-3" />
 		</a>
 	)
 }

app/integration/docker.ts

@@ -0,0 +1,124 @@
+import { access, constants } from 'node:fs/promises'
+import { setTimeout } from 'node:timers/promises'
+
+import { Client } from 'undici'
+
+import { HeadscaleError, pull } from '~/utils/headscale'
+
+import type { Integration } from '.'
+
+let url: URL | undefined
+let container: string | undefined
+
+async function preflight() {
+	const path = process.env.DOCKER_SOCK ?? 'unix:///var/run/docker.sock'
+
+	try {
+		url = new URL(path)
+	} catch {
+		return false
+	}
+
+	// The API is available as an HTTP endpoint
+	if (url.protocol === 'tcp:') {
+		url.protocol = 'http:'
+	}
+
+	// Check if the socket is accessible
+	if (url.protocol === 'unix:') {
+		try {
+			await access(path, constants.R_OK)
+		} catch {
+			return false
+		}
+	}
+
+	if (url.protocol === 'http:') {
+		try {
+			await fetch(new URL('/v1.30/version', url).href)
+		} catch {
+			return false
+		}
+	}
+
+	if (url.protocol !== 'http:' && url.protocol !== 'unix:') {
+		return false
+	}
+
+	container = process.env.HEADSCALE_CONTAINER
+		?.trim()
+		.toLowerCase()
+
+	if (!container || container.length === 0) {
+		return false
+	}
+
+	return true
+}
+
+async function sighup() {
+	if (!url || !container) {
+		return
+	}
+
+	// Supports the DOCKER_SOCK environment variable
+	const client = url.protocol === 'unix:'
+		? new Client('http://localhost', {
+			socketPath: url.href,
+		})
+		: new Client(url.href)
+
+	const response = await client.request({
+		method: 'POST',
+		path: `/v1.30/containers/${container}/kill?signal=SIGHUP`,
+	})
+
+	if (!response.statusCode || response.statusCode !== 204) {
+		throw new Error('Failed to send SIGHUP to Headscale')
+	}
+}
+
+async function restart() {
+	if (!url || !container) {
+		return
+	}
+
+	// Supports the DOCKER_SOCK environment variable
+	const client = url.protocol === 'unix:'
+		? new Client('http://localhost', {
+			socketPath: url.href,
+		})
+		: new Client(url.href)
+
+	const response = await client.request({
+		method: 'POST',
+		path: `/v1.30/containers/${container}/restart`,
+	})
+
+	if (!response.statusCode || response.statusCode !== 204) {
+		throw new Error('Failed to restart Headscale')
+	}
+
+	// Wait for Headscale to restart before continuing
+	let attempts = 0
+	// eslint-disable-next-line @typescript-eslint/no-unnecessary-condition, no-constant-condition
+	while (true) {
+		try {
+			await pull('v1', '')
+			return
+		} catch (error) {
+			if (error instanceof HeadscaleError && error.status === 401) {
+				break
+			}
+
+			if (attempts > 10) {
+				throw new Error('Headscale did not restart in time')
+			}
+
+			attempts++
+			await setTimeout(1000)
+		}
+	}
+}
+
+export default { preflight, sighup, restart } satisfies Integration

app/integration/index.ts

@@ -0,0 +1,57 @@
+import docker from './docker'
+import proc from './proc'
+
+export interface Integration {
+	preflight: () => Promise<boolean>
+	sighup?: () => Promise<void>
+	restart?: () => Promise<void>
+}
+
+// Because we previously supported the Docker integration by
+// checking for the HEADSCALE_CONTAINER variable, we need to
+// check for it here as well.
+//
+// This ensures that when people upgrade from older versions
+// of Headplane, they don't explicitly need to define the new
+// HEADSCALE_INTEGRATION variable that is needed to configure
+// an integration.
+export async function checkIntegration() {
+	let integration = process.env.HEADSCALE_INTEGRATION
+		?.trim()
+		.toLowerCase()
+
+	// Old HEADSCALE_CONTAINER variable upgrade path
+	if (!integration && process.env.HEADSCALE_CONTAINER) {
+		integration = 'docker'
+	}
+
+	if (!integration) {
+		console.log('Running Headplane without any integrations')
+		return
+	}
+
+	let module: Integration | undefined
+	try {
+		module = getIntegration(integration)
+		await module.preflight()
+	} catch (error) {
+		console.error('Failed to load integration', error)
+		return
+	}
+
+	return module
+}
+
+function getIntegration(name: string) {
+	switch (name) {
+		case 'docker': {
+			return docker
+		}
+		case 'proc': {
+			return proc
+		}
+		default: {
+			throw new Error(`Unknown integration: ${name}`)
+		}
+	}
+}

app/integration/proc.ts

@@ -0,0 +1,80 @@
+import { access, constants, readdir, readFile } from 'node:fs/promises'
+import { platform } from 'node:os'
+import { join, resolve } from 'node:path'
+import { kill } from 'node:process'
+
+import type { Integration } from '.'
+
+// Check if we have a /proc and if it's readable
+async function preflight() {
+	if (platform() !== 'linux') {
+		return false
+	}
+
+	const dir = resolve('/proc')
+	try {
+		await access(dir, constants.R_OK)
+		return true
+	} catch (error) {
+		console.error('Failed to access /proc', error)
+		return false
+	}
+}
+
+async function findPid() {
+	const dirs = await readdir('/proc')
+
+	const promises = dirs.map(async (dir) => {
+		const pid = Number.parseInt(dir, 10)
+
+		if (Number.isNaN(pid)) {
+			return
+		}
+
+		const path = join('/proc', dir, 'cmdline')
+		try {
+			const data = await readFile(path, 'utf8')
+			if (data.includes('headscale')) {
+				return pid
+			}
+		} catch {}
+	})
+
+	const results = await Promise.allSettled(promises)
+	const pids = []
+
+	for (const result of results) {
+		if (result.status === 'fulfilled') {
+			pids.push(result.value)
+		}
+	}
+
+	if (pids.length > 1) {
+		console.warn('Found multiple Headscale processes', pids)
+		console.log('Disabling the /proc integration')
+		return
+	}
+
+	if (pids.length === 0) {
+		console.warn('Could not find Headscale process')
+		console.log('Disabling the /proc integration')
+		return
+	}
+
+	return pids[0]
+}
+
+async function sighup() {
+	const pid = await findPid()
+	if (!pid) {
+		return
+	}
+
+	try {
+		kill(pid, 'SIGHUP')
+	} catch (error) {
+		console.error('Failed to send SIGHUP to Headscale', error)
+	}
+}
+
+export default { preflight, sighup } satisfies Integration

app/routes/_data.acls._index/route.tsx

@@ -9,7 +9,6 @@ import Link from '~/components/Link'
 import Notice from '~/components/Notice'
 import { cn } from '~/utils/cn'
 import { loadAcl, loadContext, patchAcl } from '~/utils/config/headplane'
-import { sighupHeadscale } from '~/utils/docker'
 import { getSession } from '~/utils/sessions'
 
 import Editor from './editor'
@@ -47,8 +46,8 @@ export async function action({ request }: ActionFunctionArgs) {
 	const data = await request.json() as { acl: string }
 	await patchAcl(data.acl)
 
-	if (context.docker) {
-		await sighupHeadscale()
+	if (context.integration?.sighup) {
+		await context.integration.sighup()
 	}
 
 	return json({ success: true })

app/routes/_data.dns._index/route.tsx

@@ -5,7 +5,6 @@ import Code from '~/components/Code'
 import Notice from '~/components/Notice'
 import { loadContext } from '~/utils/config/headplane'
 import { loadConfig, patchConfig } from '~/utils/config/headscale'
-import { restartHeadscale } from '~/utils/docker'
 import { getSession } from '~/utils/sessions'
 import { useLiveData } from '~/utils/useLiveData'
 
@@ -56,7 +55,11 @@ export async function action({ request }: ActionFunctionArgs) {
 
 	const data = await request.json() as Record<string, unknown>
 	await patchConfig(data)
-	await restartHeadscale()
+
+	if (context.integration?.restart) {
+		await context.integration.restart()
+	}
+
 	return json({ success: true })
 }
 

app/routes/_data.tsx

@@ -35,7 +35,8 @@ export async function loader({ request }: LoaderFunctionArgs) {
 
 	const context = await loadContext()
 	return {
-		...context,
+		acl: context.acl,
+		config: context.config,
 		user: session.get('user'),
 	}
 }

app/utils/config/headplane.ts

@@ -8,11 +8,14 @@ import { resolve } from 'node:path'
 
 import { parse } from 'yaml'
 
+import { checkIntegration, Integration } from '~/integration'
+
 import { HeadscaleConfig, loadConfig } from './headscale'
 
 export interface HeadplaneContext {
 	headscaleUrl: string
 	cookieSecret: string
+	integration: Integration | undefined
 
 	config: {
 		read: boolean
@@ -24,12 +27,6 @@ export interface HeadplaneContext {
 		write: boolean
 	}
 
-	docker?: {
-		url: string
-		sock: boolean
-		container: string
-	}
-
 	oidc?: {
 		issuer: string
 		client: string
@@ -74,9 +71,9 @@ export async function loadContext(): Promise<HeadplaneContext> {
 	context = {
 		headscaleUrl,
 		cookieSecret,
+		integration: await checkIntegration(),
 		config: await checkConfig(path, config),
 		acl: await checkAcl(config),
-		docker: await checkDocker(),
 		oidc: await checkOidc(config),
 	}
 
@@ -163,53 +160,6 @@ async function checkAcl(config?: HeadscaleConfig) {
 	}
 }
 
-async function checkDocker() {
-	const path = process.env.DOCKER_SOCK ?? 'unix:///var/run/docker.sock'
-
-	let url: URL | undefined
-	try {
-		url = new URL(path)
-	} catch {
-		return
-	}
-
-	// The API is available as an HTTP endpoint
-	if (url.protocol === 'tcp:') {
-		url.protocol = 'http:'
-	}
-
-	// Check if the socket is accessible
-	if (url.protocol === 'unix:') {
-		try {
-			await access(path, constants.R_OK)
-		} catch {
-			return
-		}
-	}
-
-	if (url.protocol === 'http:') {
-		try {
-			await fetch(new URL('/v1.30/version', url).href)
-		} catch {
-			return
-		}
-	}
-
-	if (url.protocol !== 'http:' && url.protocol !== 'unix:') {
-		return
-	}
-
-	if (!process.env.HEADSCALE_CONTAINER) {
-		return
-	}
-
-	return {
-		url: url.href,
-		sock: url.protocol === 'unix:',
-		container: process.env.HEADSCALE_CONTAINER,
-	}
-}
-
 async function checkOidc(config?: HeadscaleConfig) {
 	const disableKeyLogin = process.env.DISABLE_API_KEY_LOGIN === 'true'
 	const rootKey = process.env.ROOT_API_KEY ?? process.env.API_KEY

app/utils/docker.ts

@@ -1,76 +0,0 @@
-import { setTimeout } from 'node:timers/promises'
-
-import { Client } from 'undici'
-
-import { loadContext } from './config/headplane'
-import { HeadscaleError, pull } from './headscale'
-
-export async function sighupHeadscale() {
-	const context = await loadContext()
-	if (!context.docker) {
-		return
-	}
-
-	// Supports the DOCKER_SOCK environment variable
-	const client = context.docker.sock
-		? new Client('http://localhost', {
-			socketPath: context.docker.url,
-		})
-		: new Client(context.docker.url)
-
-	const response = await client.request({
-		method: 'POST',
-		path: `/v1.30/containers/${context.docker.container}/kill?signal=SIGHUP`,
-	})
-
-	if (!response.statusCode || response.statusCode !== 204) {
-		throw new Error('Failed to send SIGHUP to Headscale')
-	}
-}
-
-export async function restartHeadscale() {
-	const context = await loadContext()
-	if (!context.docker) {
-		return
-	}
-
-	// Supports the DOCKER_SOCK environment variable
-	const client = context.docker.sock
-		? new Client('http://localhost', {
-			socketPath: context.docker.url,
-		})
-		: new Client(context.docker.url)
-
-	const response = await client.request({
-		method: 'POST',
-		path: `/v1.30/containers/${context.docker.container}/restart`,
-	})
-
-	if (!response.statusCode || response.statusCode !== 204) {
-		throw new Error('Failed to restart Headscale')
-	}
-
-	// Wait for Headscale to restart before continuing
-	let attempts = 0
-	// eslint-disable-next-line
-	while (true) {
-		try {
-			// Acceptable blank because ROOT_API_KEY is not required
-			await pull('v1/apikey', context.oidc?.rootKey ?? '')
-			return
-		} catch (error) {
-			// This means the server is up but the API key is invalid
-			// This can happen if the user only uses ROOT_API_KEY via cookies
-			if (error instanceof HeadscaleError && error.status === 401) {
-				break
-			}
-
-			if (attempts > 10) {
-				throw new Error('Headscale did not restart in time')
-			}
-
-			attempts++
-			await setTimeout(1000)
-		}
-	}
-}