split long TXT records

package.json

@@ -1,10 +1,13 @@
 {
-  "name": "icy-dyndns",
+  "name": "icydns",
   "version": "1.0.0",
   "description": "",
   "main": "index.js",
   "scripts": {
-    "test": "echo \"Error: no test specified\" && exit 1"
+    "test": "echo \"Error: no test specified\" && exit 1",
+    "build": "tsc",
+    "watch": "tsc -w",
+    "start": "node src/index.js"
   },
   "keywords": [],
   "author": "",

src/dns/cache.ts

@@ -1,4 +1,4 @@
-import { CachedZone, SOARecord } from '../models/interfaces';
+import { CachedZone, DNSRecord, SOARecord } from '../models/interfaces';
 import { readZoneFile } from './reader';
 import { DNSRecordType } from './records';
 import { ReloadExecutor } from './rndc';
@@ -17,6 +17,37 @@ export class DNSCache {
     return this.cached[name] != null;
   }
 
+  search(
+    cached: CachedZone,
+    name?: string,
+    type?: DNSRecordType,
+    value?: string,
+    strict = false
+  ): DNSRecord[] {
+    return cached.zone.records.filter((zone) => {
+      if (type && zone.type !== type) {
+        return false;
+      }
+
+      if (name && zone.name !== name) {
+        return false;
+      }
+
+      if (value && ((!strict && !zone.value.includes(value as string)) ||
+                    (strict && zone.value !== value))) {
+        return false;
+      }
+
+      return true;
+    }).map((record) => {
+      const inx = cached.zone.records.indexOf(record);
+      return {
+        ...record,
+        index: inx
+      }
+    })
+  }
+
   async get(name: string): Promise<CachedZone | null> {
     const cached = this.cached[name];
     if (!cached) {

src/dns/writer.ts

@@ -1,13 +1,21 @@
 import * as fs from 'fs/promises';
-import { DNSZone, SOARecord } from '../models/interfaces';
+import { DNSRecord, DNSZone, SOARecord } from '../models/interfaces';
 import { DNSRecordType } from './records';
 
+const maxStrLength = 255;
+const magicPadding = 3;
+
+/**
+ * Splits and comments SOA record
+ * @param record
+ * @param padI
+ * @param padJ
+ * @returns new lines
+ */
 function createSOAString(record: SOARecord, padI: number, padJ: number): string[] {
   const name = record.name.padEnd(padI, ' ');
   const type = record.type.toString().padEnd(padJ, ' ');
-  const padK = ' '.padStart(
-    padI + 3
-  );
+  const padK = ' '.padStart(padI + magicPadding);
   const padL = ['serial', 'refresh', 'retry', 'expire', 'minimum']
     .reduce((previous, current) => {
       const len = `${record[current]}`.length;
@@ -24,10 +32,44 @@ function createSOAString(record: SOARecord, padI: number, padJ: number): string[
   ];
 }
 
-export function createZoneFile(zone: DNSZone, preferredLineLength = 120): string[] {
+/**
+ * Splits very long TXT records into multiple lines.
+ * Mandatory for DKIM keys, for example.
+ * @param record
+ * @param padI
+ * @param padJ
+ * @returns new lines
+ */
+function splitTXTString(record: DNSRecord, padI: number, padJ: number): string[] {
+  const name = record.name.padEnd(padI, ' ');
+  const type = record.type.toString().padEnd(padJ, ' ');
+  const strLen = maxStrLength - padI - magicPadding;
+  const padK = ' '.padStart(padI + magicPadding);
+  const splitStrings = [];
+
+  if (record.value.length < strLen) {
+    return [`${name} IN ${type} ${record.value}`];
+  }
+
+  let temporary = record.value.replace(/"/g, '');
+  while (temporary.length > strLen) {
+    splitStrings.push(temporary.substr(0, strLen));
+    temporary = temporary.substr(strLen);
+  }
+
+  splitStrings.push(temporary);
+
+  return [
+    `${name} IN ${type} (`,
+    ...splitStrings.map((str) => `${padK} "${str}"`),
+    `)`
+  ]
+}
+
+export function createZoneFile(zone: DNSZone): string[] {
   const file: string[] = [];
   file.push(`$TTL ${zone.ttl}`);
-  file.push(`; GENERATED BY icy-dyndns`);
+  file.push(`; GENERATED BY ICYDNS`);
 
   let longestName = 0;
   let longestType = 0;
@@ -49,6 +91,11 @@ export function createZoneFile(zone: DNSZone, preferredLineLength = 120): string
       return;
     }
 
+    if (record.type === DNSRecordType.TXT) {
+      file.push(...splitTXTString(record, longestName, longestType));
+      return;
+    }
+
     const name = record.name.padEnd(longestName, ' ');
     const type = record.type.toString().padEnd(longestType, ' ');
     file.push(`${name} IN ${type} ${record.value}`);

src/index.ts

@@ -18,6 +18,7 @@ const app = express();
 const api = express.Router();
 
 app.use(express.json());
+app.enable('trust proxy');
 
 const keys = new Keys();
 const rndc = ReloadExecutor.fromEnvironment();
@@ -84,35 +85,13 @@ api.get('/zone/records/:domain', domainAuthorization, async (req, res) => {
   const domain = req.params.domain;
   const cached = await getOrLoad(domain);
 
-  const type = req.query.type;
-  const name = req.query.name;
-  const value = req.query.value;
+  const type = req.query.type as DNSRecordType;
+  const name = req.query.name as string;
+  const value = req.query.value as string;
 
   if (type || name || value) {
-    const results = cached.zone.records.filter((zone) => {
-      if (type && zone.type !== type) {
-        return false;
-      }
-
-      if (name && zone.name !== name) {
-        return false;
-      }
-
-      if (value && !zone.value.includes(value as string)) {
-        return false;
-      }
-
-      return true;
-    }).map((record) => {
-      const inx = cached.zone.records.indexOf(record);
-      return {
-        ...record,
-        index: inx
-      }
-    });
-
     res.json({
-      records: results,
+      records: cache.search(cached, name, type, value),
     });
 
     return;
@@ -241,6 +220,10 @@ api.put('/zone/records/:domain', domainAuthorization, async (req, res) => {
     throw new Error('Validation error: Invalid characters');
   }
 
+  if (cache.search(cached, name, upperType, value, true).length) {
+    throw new Error('Exact same record already exists. No need to duplicate records!');
+  }
+
   zone.records.push(newRecord);
 
   await cache.update(domain, cached);