refactor network helper for e2e tests

client/tests/helpers/network.ts

@@ -9,17 +9,20 @@ interface DHCPConfig {
 }
 
 const DEFAULT_SUBNET_MASK = '255.255.255.0';
+const DEFAULT_SUBNET_MASK_OCTETS = DEFAULT_SUBNET_MASK.split('.').map(Number);
 
 function checkIsIPv4(addr: NetworkInterfaceInfo): boolean {
     return addr.family === 'IPv4' && !addr.internal;
 }
 
 function calculateNetwork(ip: number[], mask: number[]): number[] {
+    // Calculate the network address by applying the bitwise AND operation.
     // eslint-disable-next-line no-bitwise
     return ip.map((octet, i) => octet & mask[i]);
 }
 
 function calculateBroadcast(network: number[], mask: number[]): number[] {
+    // Calculate the broadcast address by ORing the network address with the inverted mask.
     // eslint-disable-next-line no-bitwise
     return network.map((octet, i) => octet | (~mask[i] & 255));
 }
@@ -27,30 +30,28 @@ function calculateBroadcast(network: number[], mask: number[]): number[] {
 export function getDHCPConfig(): DHCPConfig {
     const interfaces = networkInterfaces();
 
+    // Select the first interface that has a valid non-internal IPv4 address.
     const ipV4Interface = Object.entries(interfaces)
-        .map(([name, addresses]) => ({
+        .map(([name, addresses]) => ({ name, addresses }))
-            name,
+        .find((i) => i.addresses?.some(checkIsIPv4));
-            addresses,
-        }))
-        .find((i) => {
-            return i.addresses?.some((addr) => checkIsIPv4(addr));
-        });
 
     if (!ipV4Interface) {
         throw new Error('No suitable network interface found');
     }
 
-    const ipv4Address = ipV4Interface.addresses.find((addr) => checkIsIPv4(addr));
+    // Get the first valid IPv4 address from the interface.
+    const ipv4Address = ipV4Interface.addresses.find(checkIsIPv4);
 
     const ip = ipv4Address.address.split('.').map(Number);
-    const mask = ipv4Address.netmask?.split('.').map(Number) || DEFAULT_SUBNET_MASK.split('.');
+    const mask = ipv4Address.netmask?.split('.').map(Number) || DEFAULT_SUBNET_MASK_OCTETS;
 
     const network = calculateNetwork(ip, mask);
 
-    // Calculate first and last usable addresses (excluding network and broadcast)
+    // Calculate first usable address (network address + 1)
     const rangeStart = [...network];
     rangeStart[3] = network[3] + 1;
 
+    // Calculate broadcast address and then the last usable address (broadcast - 1)
     const broadcast = calculateBroadcast(network, mask);
     const rangeEnd = [...broadcast];
     rangeEnd[3] = broadcast[3] - 1;