feat: add netstat utils (#18)

Author: shahradelahi

.github/workflows/ci.yml

@@ -44,6 +44,7 @@ jobs:
     strategy:
       matrix:
         node-version: [18, 20]
+    name: node ${{ matrix.node-version }}
     steps:
       - uses: actions/checkout@v4
       - uses: pnpm/action-setup@v2
@@ -55,4 +56,5 @@ jobs:
           cache: 'pnpm'
 
       - run: pnpm install --frozen-lockfile
+      - run: pnpm build
       - run: pnpm test

package.json

@@ -58,6 +58,16 @@
         "types": "./dist/ip/index.d.cts",
         "default": "./dist/ip/index.cjs"
       }
+    },
+    "./netstat": {
+      "import": {
+        "types": "./dist/netstat/index.d.ts",
+        "default": "./dist/netstat/index.js"
+      },
+      "require": {
+        "types": "./dist/netstat/index.d.cts",
+        "default": "./dist/netstat/index.cjs"
+      }
     }
   },
   "author": "Shahrad Elahi <shahrad@litehex.com> (https://github.com/shahradelahi)",

src/index.ts

@@ -1 +1,2 @@
 export * as ip from './ip';
+export * as netstat from './netstat';

src/netstat/index.ts

@@ -0,0 +1,51 @@
+import { execShell } from '@/utils/exec-shell';
+import { removeDuplicate } from '@/utils/array';
+
+// ------------------------
+
+export interface ActiveConnection {
+  protocol: string;
+  program?: string;
+  recvQ: number;
+  sendQ: number;
+  address: string;
+  port: number;
+  state?: string;
+}
+
+export async function activeConnections(): Promise<ActiveConnection[]> {
+  const { error, data } = await execShell(['netstat', '-tuapn']);
+  if (error) {
+    throw error;
+  }
+
+  const lines = data.output.split('\n');
+  const ports: ActiveConnection[] = [];
+  for (const line of lines) {
+    const match =
+      /^(\w+)\s+(\d+)\s+(\d+)\s+((?:::)?(?:(?:(?:\d{1,3}\.){3}(?:\d{1,3}){1})?[0-9a-f]{0,4}:{0,2}){1,8}(?:::)?)\s+((?:::)?(?:(?:(?:\d{1,3}\.){3}(?:\d{1,3}){1})?[0-9a-f]{0,4}:{0,2}){1,8}(?:::)?\*?)\s+(\w+)?\s+(.*)$/.exec(
+        line
+      );
+    if (match) {
+      const port = match[4].split(':').at(-1);
+      const address = match[4].replace(`:${port}`, '');
+      const connection: ActiveConnection = {
+        protocol: match[1],
+        recvQ: Number(match[2]),
+        sendQ: Number(match[3]),
+        address: address,
+        port: Number(port),
+        state: match[6] ? match[6].trim() : undefined,
+        program: match[7].trim(),
+      };
+      ports.push(connection);
+    }
+  }
+
+  return ports;
+}
+
+export async function allocatedPorts(): Promise<number[]> {
+  const cns = await activeConnections();
+  return removeDuplicate(cns.map((cn) => cn.port));
+}

src/utils/array.ts

@@ -0,0 +1,9 @@
+export function removeDuplicate<T>(d: T[]): T[] {
+  const final: T[] = [];
+  for (const item of d) {
+    if (!final.includes(item)) {
+      final.push(item);
+    }
+  }
+  return final;
+}

tests/netstat/index.test.ts

@@ -0,0 +1,21 @@
+import { expect } from 'chai';
+import { IPV4_REGEX } from '@/ip';
+import { activeConnections, allocatedPorts } from 'node-netkit/netstat';
+
+describe('Active Connections', () => {
+  it('should get active connections', async () => {
+    const connections = await activeConnections();
+    expect(connections).to.be.an('array');
+    expect(connections.length).to.have.greaterThan(0);
+
+    expect(Object.keys(connections[0])).to.have.lengthOf(7);
+    expect(connections[0].address).to.match(IPV4_REGEX);
+  });
+
+  it('should get allocated ports', async () => {
+    for (const p of await allocatedPorts()) {
+      expect(p).to.be.greaterThan(0);
+      expect(p).to.be.lessThan(65535);
+    }
+  });
+});

tsconfig.json

@@ -19,7 +19,9 @@
     "allowJs": true,
     "baseUrl": ".",
     "paths": {
-      "@/*": ["src/*"]
+      "@/*": ["src/*"],
+      "node-netkit/*": ["dist/*"],
+      "node-netkit": ["dist/index.js"]
     },
     "outDir": "build"
   },

tsup.config.ts

@@ -3,7 +3,7 @@ import { defineConfig } from 'tsup';
 export default defineConfig({
   clean: true,
   dts: true,
-  entry: ['src/index.ts', 'src/ip/index.ts'],
+  entry: ['src/index.ts', 'src/ip/index.ts', 'src/netstat/index.ts'],
   format: ['cjs', 'esm'],
   target: 'esnext',
   outDir: 'dist',