Added DNS toggling functionality with environment validation

micthiesen · Oct 18, 2024 · ca44a76 · ca44a76
1 parent a71e36f
commit ca44a76
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Showing 6 changed files with 105 additions and 97 deletions.
diff --git a/biome.json b/biome.json
@@ -1,4 +1,7 @@
 {
+  "files": {
+    "ignore": ["dist"]
+  },
   "linter": {
     "enabled": true,
     "rules": {

diff --git a/src/dns.ts b/src/dns.ts
@@ -0,0 +1,39 @@
+import { parseDnsServers } from "./parsing";
+import { getSshConnection, type SNodeSSH } from "./ssh";
+
+let timeoutId: NodeJS.Timeout | null = null;
+const RESTORE_DELAY = 1000 * 5;
+
+const ALT_DNS_SERVERS: [string, string] = ["1.1.1.1", "1.0.0.1"];
+
+export async function toggleDns(ssh: SNodeSSH) {
+  if (timeoutId) clearTimeout(timeoutId);
+
+  const originalDnsServers = parseDnsServers(await ssh.execSafe("show"));
+  console.log(`Found existing DNS servers: ${originalDnsServers}`);
+
+  console.log("Setting alternative DNS servers...");
+  await setDnsServers(ssh, ALT_DNS_SERVERS);
+
+  timeoutId = setTimeout(genRestoreDnsServers(originalDnsServers), RESTORE_DELAY);
+  console.log(`Scheduled restore in ${RESTORE_DELAY}ms`);
+}
+
+function genRestoreDnsServers(originalDnsServers: [string, string]) {
+  return async () => {
+    console.log("Restoring original DNS servers...");
+    let ssh: SNodeSSH | undefined;
+    try {
+      ssh = await getSshConnection();
+      await setDnsServers(ssh, originalDnsServers);
+    } finally {
+      if (ssh) ssh.dispose();
+    }
+  };
+}
+
+async function setDnsServers(ssh: SNodeSSH, dns: [string, string]) {
+  console.log(`Setting DNS servers to ${dns}`);
+  // ssh.execCommand(`configure set service dns forwarding name-server ${dns[0]}`);
+  // ssh.execCommand(`configure set service dns forwarding name-server ${dns[1]}`);
+}
diff --git a/src/env.ts b/src/env.ts
@@ -0,0 +1,12 @@
+import { z } from "zod";
+
+const env = z
+  .object({
+    PUSHOVER_USER: z.string(),
+    PUSHOVER_TOKEN: z.string(),
+    SSH_USERNAME: z.string(),
+    SSH_PASSWORD: z.string(),
+    ROUTER_HOSTNAME: z.string().ip({ version: "v4" }),
+  })
+  .parse(process.env);
+export default env;
diff --git a/src/index.ts b/src/index.ts
@@ -1,51 +1,18 @@
 import { type HttpBindings, serve } from "@hono/node-server";
 import { Hono } from "hono";
-import { NodeSSH } from "node-ssh";
-import { z } from "zod";
-
-type SNodeSSH = NodeSSH & {
-  execSafe: (command: string) => Promise<string>;
-};
-
-const ALT_DNS_SERVERS: [string, string] = ["1.1.1.1", "1.0.0.1"];
-
-const env = z
-  .object({
-    PUSHOVER_USER: z.string(),
-    PUSHOVER_TOKEN: z.string(),
-    SSH_USERNAME: z.string(),
-    SSH_PASSWORD: z.string(),
-    ROUTER_HOSTNAME: z.string().ip({ version: "v4" }),
-  })
-  .parse(process.env);
+import { toggleDns } from "./dns";
+import { getSshConnection, type SNodeSSH } from "./ssh";
 
 const app = new Hono<{ Bindings: HttpBindings }>();
 
-let timeoutId: NodeJS.Timeout | null = null;
-const RESTORE_DELAY = 1000 * 5;
-
 app.get("/toggle-dns", async (c) => {
-  if (timeoutId) clearTimeout(timeoutId);
   console.log(`${c.env.incoming.method} ${c.env.incoming.url}`);
 
   let ssh: SNodeSSH | undefined;
   try {
     ssh = await getSshConnection();
-    const result = await ssh.execSafe("show");
-    return c.text(`Resp: ${result}`);
-    if (result.stderr) return c.text(`Error: ${result.stderr}`);
-
-    const originalDnsServers = extractDnsServers(result.stdout);
-    console.log(`Found existing DNS servers: ${originalDnsServers}`);
-
-    console.log("Setting alternative DNS servers...");
-    await setDnsServers(ssh, ALT_DNS_SERVERS);
-
-    timeoutId = setTimeout(genRestoreDnsServers(originalDnsServers), RESTORE_DELAY);
-    console.log(`Scheduled restore in ${RESTORE_DELAY}ms`);
-
-    const resp = c.text("Hono meets Node.js");
-    return resp;
+    await toggleDns(ssh);
+    return c.text("DNS servers toggled");
   } catch (err: any) {
     return c.text(`Error: ${err.message}`);
   } finally {
@@ -54,64 +21,5 @@ app.get("/toggle-dns", async (c) => {
 });
 
 serve({ fetch: app.fetch, port: 5888 }, (info) => {
-  console.log(`Listening on http://localhost:${info.port}`);
+  console.log(`\nListening on http://localhost:${info.port}`);
 });
-
-function genRestoreDnsServers(originalDnsServers: [string, string]) {
-  return async () => {
-    console.log("Restoring original DNS servers...");
-    let ssh: SNodeSSH | undefined;
-    try {
-      ssh = await getSshConnection();
-      await setDnsServers(ssh, originalDnsServers);
-    } finally {
-      if (ssh) ssh.dispose();
-    }
-  };
-}
-
-async function setDnsServers(ssh: SNodeSSH, dns: [string, string]) {
-  console.log(`Setting DNS servers to ${dns}`);
-  // ssh.execCommand(`configure set service dns forwarding name-server ${dns[0]}`);
-  // ssh.execCommand(`configure set service dns forwarding name-server ${dns[1]}`);
-}
-
-async function getSshConnection(): Promise<SNodeSSH> {
-  const ssh = new NodeSSH() as SNodeSSH;
-  await ssh.connect({
-    host: env.ROUTER_HOSTNAME,
-    username: env.SSH_USERNAME,
-    password: env.SSH_PASSWORD,
-    tryKeyboard: false,
-  });
-  ssh.execSafe = async (command: string) => {
-    console.log(command);
-    const result = await ssh.execCommand(command);
-    if (result.stderr) console.warn(result.stderr);
-    if (result.stderr) throw new Error(`Error executing command: ${result.stderr}`);
-    if (result.stdout) console.log(result.stdout);
-    return result.stdout;
-  };
-
-  await ssh.execSafe("export PS1=true");
-  await ssh.execSafe("export _OFR_CONFIGURE=ok");
-  await ssh.execSafe("source ~/.bashrc");
-  await ssh.execSafe("alias");
-
-  return ssh;
-}
-
-function extractDnsServers(text: string): [string, string] {
-  const dnsRegex = /dns-server\s+([\d.]+)/g;
-  const matches = Array.from(text.matchAll(dnsRegex)).map((match) => match[1]);
-
-  if (matches.length === 2) return [matches[0], matches[1]];
-
-  throw new Error(`Could not extract DNS servers: ${text}`);
-}
-
-async function execSafe(ssh: NodeSSH, command: string) {
-  const result = ssh.execCommand(command);
-  if (result.stderr) throw new Error(`Error executing command: ${result.stderr}`);
-  return result.stdout;
-}
diff --git a/src/parsing.ts b/src/parsing.ts
@@ -0,0 +1,11 @@
+import { z } from "zod";
+
+const dnsRegex = /dns-server\s+([\d.]+)/g;
+const dnsSchema = z
+  .string()
+  .transform((text) => Array.from(text.matchAll(dnsRegex)).map((match) => match[1]))
+  .pipe(z.tuple([z.string().ip({ version: "v4" }), z.string().ip({ version: "v4" })]));
+
+export function parseDnsServers(text: string): [string, string] {
+  return dnsSchema.parse(text);
+}
diff --git a/src/ssh.ts b/src/ssh.ts
@@ -0,0 +1,35 @@
+import { NodeSSH } from "node-ssh";
+import env from "./env";
+
+export type SNodeSSH = NodeSSH & {
+  execSafe: (command: string) => Promise<string>;
+};
+
+export async function getSshConnection(): Promise<SNodeSSH> {
+  const ssh = new NodeSSH() as SNodeSSH;
+  await ssh.connect({
+    host: env.ROUTER_HOSTNAME,
+    username: env.SSH_USERNAME,
+    password: env.SSH_PASSWORD,
+    tryKeyboard: false,
+  });
+  ssh.execSafe = async (command: string) => {
+    console.log(`>>> ${command}`);
+    const result = await ssh.execCommand(command);
+    if (result.stderr) console.warn(prefixCaret(result.stderr));
+    if (result.stderr) throw new Error(`Error executing command: ${result.stderr}`);
+    if (result.stdout) console.log(prefixCaret(result.stdout));
+    return result.stdout;
+  };
+
+  await ssh.execSafe("export PS1=true");
+  await ssh.execSafe("export _OFR_CONFIGURE=ok");
+  await ssh.execSafe("source ~/.bashrc");
+  await ssh.execSafe("alias");
+
+  return ssh;
+}
+
+function prefixCaret(text: string): string {
+  return text.replace(/^/gm, "> ");
+}