refactor network helper for e2e tests

client/tests/helpers/network.ts

@@ -1,4 +1,5 @@
 import { networkInterfaces } from 'os';
+import type { NetworkInterfaceInfo } from 'node:os';
 
 interface DHCPConfig {
     interfaceName: string;
@@ -7,32 +8,57 @@ interface DHCPConfig {
     subnetMask: string;
 }
 
+const DEFAULT_SUBNET_MASK = '255.255.255.0';
+
+function checkIsIPv4(addr: NetworkInterfaceInfo): boolean {
+    return addr.family === 'IPv4' && !addr.internal;
+}
+
+function calculateNetwork(ip: number[], mask: number[]): number[] {
+    // eslint-disable-next-line no-bitwise
+    return ip.map((octet, i) => octet & mask[i]);
+}
+
+function calculateBroadcast(network: number[], mask: number[]): number[] {
+    // eslint-disable-next-line no-bitwise
+    return network.map((octet, i) => octet | (~mask[i] & 255));
+}
+
 export function getDHCPConfig(): DHCPConfig {
     const interfaces = networkInterfaces();
-    for (const [name, addresses] of Object.entries(interfaces)) {
-        const ipv4Address = addresses?.find((addr) => addr.family === 'IPv4' && !addr.internal);
-        if (ipv4Address) {
-            const ip = ipv4Address.address.split('.').map(Number);
-            const mask = ipv4Address.netmask?.split('.').map(Number) || [255, 255, 255, 0];
-            
-            // Calculate network address
-            const network = ip.map((octet, i) => octet & mask[i]);
-            
-            // Calculate first and last usable addresses (excluding network and broadcast)
-            const rangeStart = [...network];
-            rangeStart[3] = network[3] + 1;
-            
-            const broadcast = network.map((octet, i) => octet | (~mask[i] & 255));
-            const rangeEnd = [...broadcast];
-            rangeEnd[3] = broadcast[3] - 1;
 
-            return {
+    const ipV4Interface = Object.entries(interfaces)
-                interfaceName: name,
+        .map(([name, addresses]) => ({
-                rangeStart: rangeStart.join('.'),
+            name,
-                rangeEnd: rangeEnd.join('.'),
+            addresses,
-                subnetMask: ipv4Address.netmask || '255.255.255.0',
+        }))
-            };
+        .find((i) => {
-        }
+            return i.addresses?.some((addr) => checkIsIPv4(addr));
+        });
+
+    if (!ipV4Interface) {
+        throw new Error('No suitable network interface found');
     }
-    throw new Error('No suitable network interface found');
+
+    const ipv4Address = ipV4Interface.addresses.find((addr) => checkIsIPv4(addr));
+
+    const ip = ipv4Address.address.split('.').map(Number);
+    const mask = ipv4Address.netmask?.split('.').map(Number) || DEFAULT_SUBNET_MASK.split('.');
+
+    const network = calculateNetwork(ip, mask);
+
+    // Calculate first and last usable addresses (excluding network and broadcast)
+    const rangeStart = [...network];
+    rangeStart[3] = network[3] + 1;
+
+    const broadcast = calculateBroadcast(network, mask);
+    const rangeEnd = [...broadcast];
+    rangeEnd[3] = broadcast[3] - 1;
+
+    return {
+        interfaceName: ipV4Interface.name,
+        rangeStart: rangeStart.join('.'),
+        rangeEnd: rangeEnd.join('.'),
+        subnetMask: ipv4Address.netmask || DEFAULT_SUBNET_MASK,
+    };
 }