Added option to parse XML from a string

Author: rmraya

README.md

@@ -4,6 +4,7 @@ Open source XML library written in TypeScript
 
 Implements a SAX parser that exposes the these methods from the `ContentHandler` interface:
 
+* initialize(): void;
 * setCatalog(catalog: Catalog): void;
 * startDocument(): void;
 * endDocument(): void;
@@ -53,10 +54,16 @@ export class Test {
             let contentHandler: ContentHandler = new DOMBuilder();
             let xmlParser = new SAXParser();
             xmlParser.setContentHandler(contentHandler);
-            xmlParser.parse("test.xml");
+            xmlParser.parseFile("test.xml");
             let doc: XMLDocument = (contentHandler as DOMBuilder).getDocument();
             let root: XMLElement = doc.getRoot();
             console.log(root.toString());
+
+            //  build the document again, this time from a string
+            xmlParser.parseString(doc.toString());
+            let newDoc = (contentHandler as DOMBuilder).getDocument();
+            console.log(newDoc.getRoot().toString());
+
         } catch (error: any) {
             if (error instanceof Error) {
                 console.log(error.message);

build.sh

@@ -0,0 +1,5 @@
+rm -rf dist/
+rm -rf node_modules/
+rm package-lock.json
+npm install
+npm run build

package.json

@@ -1,7 +1,7 @@
 {
   "name": "typesxml",
   "productName": "TypesXML",
-  "version": "1.1.0",
+  "version": "1.2.0",
   "description": "Open source XML library written in TypeScript",
   "scripts": {
     "build": "tsc"
@@ -22,7 +22,7 @@
     "url": "https://github.com/rmraya/TypesXML.git"
   },
   "devDependencies": {
-    "@types/node": "^20.9.4",
+    "@types/node": "^20.10.0",
     "typescript": "^5.3.2"
   }
 }

sonar-project.properties

@@ -2,7 +2,7 @@
 sonar.projectKey=TypesXML
 # this is the name displayed in the SonarQube UI
 sonar.projectName=TypesXML
-sonar.projectVersion=1.1.0
+sonar.projectVersion=1.2.0
 
 # Path is relative to the sonar-project.properties file. Replace "\" by "/" on Windows.
 # Since SonarQube 4.2, this property is optional if sonar.modules is set. 

ts/Catalog.ts

@@ -51,7 +51,7 @@ export class Catalog {
         let contentHandler: ContentHandler = new DOMBuilder();
         let parser: SAXParser = new SAXParser();
         parser.setContentHandler(contentHandler);
-        parser.parse(catalogFile);
+        parser.parseFile(catalogFile);
         let catalogDocument: XMLDocument = (contentHandler as DOMBuilder).getDocument();
         let catalogRoot: XMLElement = catalogDocument.getRoot();
         if (catalogRoot.getName() !== 'catalog') {
@@ -245,8 +245,7 @@ export class Catalog {
 
     matchSystem(systemId: string): string {
         if (systemId) {
-            for (let i: number = 0; i < this.systemRewrites.length; i++) {
-                let pair: string[] = this.systemRewrites[i];
+            for (let pair of this.systemRewrites) {
                 if (systemId.startsWith(pair[0])) {
                     systemId = pair[1] + systemId.substring(pair[0].length);
                 }

ts/ContentHandler.ts

@@ -15,6 +15,7 @@ import { XMLAttribute } from "./XMLAttribute";
 
 export interface ContentHandler {
 
+    initialize(): void;
     setCatalog(catalog: Catalog): void;
 
     startDocument(): void;

ts/DOMBuilder.ts

@@ -20,7 +20,7 @@ export class DOMBuilder implements ContentHandler {
     catalog: Catalog;
     grammarUrl: string;
 
-    constructor() {
+    initialize(): void {
         this.document = new XMLDocument();
         this.stack = new Array();
         this.inCdData = false;

ts/FileReader.ts

@@ -10,9 +10,10 @@
  *     Maxprograms - initial API and implementation
  *******************************************************************************/
 
-import { openSync, readSync, closeSync, statSync, Stats } from "fs";
+import { Stats, closeSync, openSync, readSync, statSync } from "fs";
+import { XMLReader } from "./XMLReader";
 
-export class FileReader {
+export class FileReader implements XMLReader {
 
     fileHandle: number;
     encoding: BufferEncoding;

ts/SAXParser.ts

@@ -12,17 +12,17 @@
 
 import { ContentHandler } from "./ContentHandler";
 import { FileReader } from "./FileReader";
+import { StringReader } from "./StringReader";
 import { XMLAttribute } from "./XMLAttribute";
+import { XMLReader } from "./XMLReader";
 import { XMLUtils } from "./XMLUtils";
 
 export class SAXParser {
 
     contentHandler: ContentHandler;
-    reader: FileReader;
+    reader: XMLReader;
     pointer: number;
     buffer: string;
-    fileSize: number;
-    encoding: BufferEncoding;
     elementStack: number;
     characterRun: string;
     rootParsed: boolean;
@@ -38,11 +38,26 @@ export class SAXParser {
         this.contentHandler = contentHandler;
     }
 
-    parse(path: string, encoding?: BufferEncoding): void {
-        this.encoding = encoding ? encoding : FileReader.detectEncoding(path);
+    parseFile(path: string, encoding?: BufferEncoding): void {
+        if (!this.contentHandler) {
+            throw new Error('ContentHandler not set');
+        }
+        if (!encoding) {
+            encoding = FileReader.detectEncoding(path);
+        }
         this.reader = new FileReader(path, encoding);
-        this.fileSize = this.reader.getFileSize();
         this.buffer = this.reader.read();
+        this.contentHandler.initialize();
+        this.readDocument();
+    }
+
+    parseString(string: string): void {
+        if (!this.contentHandler) {
+            throw new Error('ContentHandler not set');
+        }
+        this.reader = new StringReader(string);
+        this.buffer = this.reader.read();
+        this.contentHandler.initialize();
         this.readDocument();
     }
 

ts/StringReader.ts

@@ -0,0 +1,40 @@
+/*******************************************************************************
+ * Copyright (c) 2023 Maxprograms.
+ *
+ * This program and the accompanying materials
+ * are made available under the terms of the Eclipse   License 1.0
+ * which accompanies this distribution, and is available at
+ * https://www.eclipse.org/org/documents/epl-v10.html
+ *
+ * Contributors:
+ *     Maxprograms - initial API and implementation
+ *******************************************************************************/
+import { XMLReader } from "./XMLReader";
+
+export class StringReader implements XMLReader {
+
+    CHUNK_SIZE: number = 4096;
+
+    data: string;
+    position: number;
+
+    constructor(data: string) {
+        this.data = data;
+        this.position = 0;
+    }
+
+    dataAvailable(): boolean {
+        return this.position < this.data.length;
+    }
+
+    read(): string {
+        let amount: number = this.CHUNK_SIZE;
+        if (this.position + this.CHUNK_SIZE > this.data.length) {
+            amount = this.data.length - this.position;
+        }
+        let result: string = this.data.substring(this.position, amount);
+        this.position += amount;
+        return result;
+    }
+
+}