✨ Add DNS module

src/modules/dns/dns.interface.ts

@@ -0,0 +1,23 @@
+import { MxRecord, NaptrRecord, SoaRecord, SrvRecord, AnyRecord } from 'dns';
+
+export type RecordType =
+  | 'A'
+  | 'AAAA'
+  | 'ANY'
+  | 'CNAME'
+  | 'MX'
+  | 'NAPTR'
+  | 'NS'
+  | 'PTR'
+  | 'SOA'
+  | 'SRV'
+  | 'TXT';
+
+export type RecordResult =
+  | Array<string>
+  | Array<MxRecord>
+  | Array<NaptrRecord>
+  | SoaRecord
+  | Array<SrvRecord>
+  | Array<Array<string>>
+  | Array<AnyRecord>;

src/modules/dns/dns.service.ts

@@ -1,4 +1,29 @@
 import { Injectable } from '@nestjs/common';
+import dns from 'dns';
+import { RecordType, RecordResult } from './dns.interface';
 
 @Injectable()
-export class DnsService {}
+export class DnsService {
+  async lookup(
+    hostname: string,
+    recordType: RecordType,
+  ): Promise<RecordResult> {
+    try {
+      return await this.unsafeLookup(hostname, recordType);
+    } catch (error) {
+      return [];
+    }
+  }
+
+  private unsafeLookup(
+    hostname: string,
+    recordType: RecordType,
+  ): Promise<RecordResult> {
+    return new Promise((resolve, reject) => {
+      dns.resolve(hostname, recordType, (error, records) => {
+        if (error) return reject(error);
+        resolve(records);
+      });
+    });
+  }
+}