3.0.35

assets/denoentry.ts

@@ -0,0 +1 @@
+console.log('Hello from deno');

npmextra.json

@@ -6,12 +6,34 @@
   "gitzone": {
     "projectType": "npm",
     "module": {
-      "githost": "gitlab.com",
+      "githost": "code.foss.global",
       "gitscope": "push.rocks",
       "gitrepo": "smartstream",
       "description": "simplifies access to node streams",
       "npmPackagename": "@push.rocks/smartstream",
-      "license": "MIT"
-    }
+      "license": "MIT",
+      "keywords": [
+        "node.js",
+        "streams",
+        "stream manipulation",
+        "pipeline",
+        "data processing",
+        "async transformation",
+        "event handling",
+        "backpressure management",
+        "readable streams",
+        "writable streams",
+        "duplex streams",
+        "transform streams",
+        "file streaming",
+        "buffer streams",
+        "stream utilities",
+        "stream intake",
+        "stream output"
+      ]
+    }
+  },
+  "tsdoc": {
+    "legal": "\n## License and Legal Information\n\nThis repository contains open-source code that is licensed under the MIT License. A copy of the MIT License can be found in the [license](license) file within this repository. \n\n**Please note:** The MIT License does not grant permission to use the trade names, trademarks, service marks, or product names of the project, except as required for reasonable and customary use in describing the origin of the work and reproducing the content of the NOTICE file.\n\n### Trademarks\n\nThis project is owned and maintained by Task Venture Capital GmbH. The names and logos associated with Task Venture Capital GmbH and any related products or services are trademarks of Task Venture Capital GmbH and are not included within the scope of the MIT license granted herein. Use of these trademarks must comply with Task Venture Capital GmbH's Trademark Guidelines, and any usage must be approved in writing by Task Venture Capital GmbH.\n\n### Company Information\n\nTask Venture Capital GmbH  \nRegistered at District court Bremen HRB 35230 HB, Germany\n\nFor any legal inquiries or if you require further information, please contact us via email at hello@task.vc.\n\nBy using this repository, you acknowledge that you have read this section, agree to comply with its terms, and understand that the licensing of the code does not imply endorsement by Task Venture Capital GmbH of any derivative works.\n"
   }
 }

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@push.rocks/smartstream",
-  "version": "3.0.6",
+  "version": "3.0.35",
   "private": false,
   "description": "simplifies access to node streams",
   "main": "dist_ts/index.js",
@@ -22,16 +22,18 @@
   },
   "homepage": "https://gitlab.com/push.rocks/smartstream#readme",
   "devDependencies": {
-    "@git.zone/tsbuild": "^2.1.66",
+    "@git.zone/tsbuild": "^2.1.72",
     "@git.zone/tsrun": "^1.2.44",
-    "@git.zone/tstest": "^1.0.77",
-    "@push.rocks/smartfile": "^10.0.37",
-    "@push.rocks/tapbundle": "^5.0.15",
-    "@types/node": "^20.8.10"
+    "@git.zone/tstest": "^1.0.88",
+    "@push.rocks/smartfile": "^11.0.4",
+    "@push.rocks/tapbundle": "^5.0.17",
+    "@types/node": "^20.11.28"
   },
   "dependencies": {
+    "@push.rocks/lik": "^6.0.14",
     "@push.rocks/smartpromise": "^4.0.3",
-    "@push.rocks/smartrx": "^3.0.7"
+    "@push.rocks/smartrx": "^3.0.7",
+    "@push.rocks/webstream": "^1.0.8"
   },
   "browserslist": [
     "last 1 chrome versions"
@@ -47,5 +49,24 @@
     "cli.js",
     "npmextra.json",
     "readme.md"
+  ],
+  "keywords": [
+    "node.js",
+    "streams",
+    "stream manipulation",
+    "pipeline",
+    "data processing",
+    "async transformation",
+    "event handling",
+    "backpressure management",
+    "readable streams",
+    "writable streams",
+    "duplex streams",
+    "transform streams",
+    "file streaming",
+    "buffer streams",
+    "stream utilities",
+    "stream intake",
+    "stream output"
   ]
 }

readme.hints.md

@@ -0,0 +1 @@
+ 

readme.md

@@ -1,54 +1,147 @@
-# @pushrocks/smartstream
+# @push.rocks/smartstream
 simplifies access to node streams
 
-## Availabililty and Links
-* [npmjs.org (npm package)](https://www.npmjs.com/package/@pushrocks/smartstream)
-* [gitlab.com (source)](https://gitlab.com/pushrocks/smartstream)
-* [github.com (source mirror)](https://github.com/pushrocks/smartstream)
-* [docs (typedoc)](https://pushrocks.gitlab.io/smartstream/)
+## Install
+To install `@push.rocks/smartstream`, you can use npm or yarn as follows:
 
-## Status for master
+```bash
+npm install @push.rocks/smartstream --save
+# OR
+yarn add @push.rocks/smartstream
+```
 
-Status Category | Status Badge
--- | --
-GitLab Pipelines | [![pipeline status](https://gitlab.com/pushrocks/smartstream/badges/master/pipeline.svg)](https://lossless.cloud)
-GitLab Pipline Test Coverage | [![coverage report](https://gitlab.com/pushrocks/smartstream/badges/master/coverage.svg)](https://lossless.cloud)
-npm | [![npm downloads per month](https://badgen.net/npm/dy/@pushrocks/smartstream)](https://lossless.cloud)
-Snyk | [![Known Vulnerabilities](https://badgen.net/snyk/pushrocks/smartstream)](https://lossless.cloud)
-TypeScript Support | [![TypeScript](https://badgen.net/badge/TypeScript/>=%203.x/blue?icon=typescript)](https://lossless.cloud)
-node Support | [![node](https://img.shields.io/badge/node->=%2010.x.x-blue.svg)](https://nodejs.org/dist/latest-v10.x/docs/api/)
-Code Style | [![Code Style](https://badgen.net/badge/style/prettier/purple)](https://lossless.cloud)
-PackagePhobia (total standalone install weight) | [![PackagePhobia](https://badgen.net/packagephobia/install/@pushrocks/smartstream)](https://lossless.cloud)
-PackagePhobia (package size on registry) | [![PackagePhobia](https://badgen.net/packagephobia/publish/@pushrocks/smartstream)](https://lossless.cloud)
-BundlePhobia (total size when bundled) | [![BundlePhobia](https://badgen.net/bundlephobia/minzip/@pushrocks/smartstream)](https://lossless.cloud)
-Platform support | [![Supports Windows 10](https://badgen.net/badge/supports%20Windows%2010/yes/green?icon=windows)](https://lossless.cloud) [![Supports Mac OS X](https://badgen.net/badge/supports%20Mac%20OS%20X/yes/green?icon=apple)](https://lossless.cloud)
+This will add `@push.rocks/smartstream` to your project's dependencies.
 
 ## Usage
 
-Use TypeScript for best in class instellisense.
+The `@push.rocks/smartstream` module is designed to simplify working with Node.js streams by providing a set of utilities for creating and manipulating streams. This module makes heavy use of TypeScript for improved code quality, readability, and maintenance. ESM syntax is utilized throughout the examples.
+
+### Importing the Module
+
+Start by importing the module into your TypeScript file:
 
 ```typescript
-import { Smartstream } from 'smartstream'
-import * as gUglify from 'gulp-uglify'
-
-let mySmartstream = new Smartstream([
-    gulp.src(['./file1.js','./file2.js']),
-    gUglify(),
-    gulp.dest('./some/output/path')
-])
-
-mySmartstream.onError((err) => { /* handle error */ }) // handles all errors in stream
-myStream.onCustomEvent('myeventname', (args...) => { /* Do something */ }) // emit an custom event anywhere in your stream
-mySmartstream.run().then(() => {/* do something when stream is finished */})
+import * as smartstream from '@push.rocks/smartstream';
 ```
 
-## Contribution
+### Creating Basic Transform Streams
 
-We are always happy for code contributions. If you are not the code contributing type that is ok. Still, maintaining Open Source repositories takes considerable time and thought. If you like the quality of what we do and our modules are useful to you we would appreciate a little monthly contribution: You can [contribute one time](https://lossless.link/contribute-onetime) or [contribute monthly](https://lossless.link/contribute). :)
+The module provides utilities for creating transform streams. For example, to create a transform stream that modifies chunks of data, you can use the `createTransformFunction` utility:
 
-For further information read the linked docs at the top of this readme.
+```typescript
+import { createTransformFunction } from '@push.rocks/smartstream';
 
-> MIT licensed | **©** [Lossless GmbH](https://lossless.gmbh)
-| By using this npm module you agree to our [privacy policy](https://lossless.gmbH/privacy)
+const upperCaseTransform = createTransformFunction<string, string>(async (chunk) => {
+  return chunk.toUpperCase();
+});
 
-[![repo-footer](https://lossless.gitlab.io/publicrelations/repofooter.svg)](https://maintainedby.lossless.com)
+// Usage with pipe
+readableStream
+  .pipe(upperCaseTransform)
+  .pipe(writableStream);
+```
+
+### Handling Backpressure with SmartDuplex
+
+`SmartDuplex` is a powerful part of the `smartstream` module designed to handle backpressure effectively. Here's an example of how to create a `SmartDuplex` stream that processes data and respects the consumer's pace:
+
+```typescript
+import { SmartDuplex } from '@push.rocks/smartstream';
+
+const processDataDuplex = new SmartDuplex({
+  async writeFunction(chunk, { push }) {
+    const processedChunk = await processChunk(chunk); // Assume this is a defined asynchronous function
+    push(processedChunk);
+  }
+});
+
+sourceStream.pipe(processDataDuplex).pipe(destinationStream);
+```
+
+### Stream Combiners
+
+`Smartstream` facilitates easy combining of multiple streams into a single pipeline, handling errors and cleanup automatically. Here's how you can combine multiple streams:
+
+```typescript
+import { StreamWrapper } from '@push.rocks/smartstream';
+
+const combinedStream = new StreamWrapper([
+  readStream,       // Source stream
+  transformStream1, // Transformation
+  transformStream2, // Another transformation
+  writeStream       // Destination stream
+]);
+
+combinedStream.run()
+  .then(() => console.log('Processing completed.'))
+  .catch(err => console.error('An error occurred:', err));
+```
+
+### Working with StreamIntake
+
+`StreamIntake` allows for more dynamic control of the reading process, facilitating scenarios where data is not continuously available:
+
+```typescript
+import { StreamIntake } from '@push.rocks/smartstream';
+
+const streamIntake = new StreamIntake<string>();
+
+// Dynamically push data into the intake
+streamIntake.pushData('Hello, World!');
+streamIntake.pushData('Another message');
+
+// Signal end when no more data is to be pushed
+streamIntake.signalEnd();
+```
+
+### Real-world Scenario: Processing Large Files
+
+Consider a scenario where you need to process a large CSV file, transform the data row-by-row, and then write the results to a database or another file. With `smartstream`, you could create a pipe that reads the CSV, processes each row, and handles backpressure, ensuring efficient use of resources.
+
+```typescript
+import { SmartDuplex, createTransformFunction } from '@push.rocks/smartstream';
+import fs from 'fs';
+import csvParser from 'csv-parser'; // Assume this is a CSV parsing library
+
+const csvReadTransform = createTransformFunction<any, any>(async (row) => {
+  // Process row
+  return processedRow;
+});
+
+fs.createReadStream('path/to/largeFile.csv')
+  .pipe(csvParser())
+  .pipe(csvReadTransform)
+  .pipe(new SmartDuplex({
+    async writeFunction(chunk, { push }) {
+      await writeToDatabase(chunk); // Assume this writes to a database
+    }
+  }))
+  .on('finish', () => console.log('File processed successfully.'));
+```
+
+This example demonstrates reading a large CSV file, transforming each row with `createTransformFunction`, and using a `SmartDuplex` to manage the processed data flow efficiently, ensuring no data is lost due to backpressure issues.
+
+### Conclusion
+
+`@push.rocks/smartstream` offers a robust set of tools for working with Node.js streams, providing a more intuitive and reliable way to create, manipulate, and combine streams. By leveraging TypeScript and ESM syntax, `smartstream` enables developers to build more maintainable and type-safe stream-based solutions.
+
+For more detailed examples and documentation, visit the [GitLab Repository](https://gitlab.com/push.rocks/smartstream) or the [GitHub Mirror](https://github.com/pushrocks/smartstream).
+
+## License and Legal Information
+
+This repository contains open-source code that is licensed under the MIT License. A copy of the MIT License can be found in the [license](license) file within this repository. 
+
+**Please note:** The MIT License does not grant permission to use the trade names, trademarks, service marks, or product names of the project, except as required for reasonable and customary use in describing the origin of the work and reproducing the content of the NOTICE file.
+
+### Trademarks
+
+This project is owned and maintained by Task Venture Capital GmbH. The names and logos associated with Task Venture Capital GmbH and any related products or services are trademarks of Task Venture Capital GmbH and are not included within the scope of the MIT license granted herein. Use of these trademarks must comply with Task Venture Capital GmbH's Trademark Guidelines, and any usage must be approved in writing by Task Venture Capital GmbH.
+
+### Company Information
+
+Task Venture Capital GmbH  
+Registered at District court Bremen HRB 35230 HB, Germany
+
+For any legal inquiries or if you require further information, please contact us via email at hello@task.vc.
+
+By using this repository, you acknowledge that you have read this section, agree to comply with its terms, and understand that the licensing of the code does not imply endorsement by Task Venture Capital GmbH of any derivative works.

test/test.backpressure.ts

@@ -0,0 +1,68 @@
+import { tap, expect } from '@push.rocks/tapbundle';
+import { SmartDuplex, type ISmartDuplexOptions, StreamWrapper } from '../ts/index.js';
+
+tap.test('should run backpressure test', async (toolsArg) => {
+  const done = toolsArg.defer();
+  async function testBackpressure() {
+    const stream1 = new SmartDuplex({
+      name: 'stream1',
+      objectMode: true,
+      writeFunction: async (chunk, tools) => {
+        await new Promise((resolve) => setTimeout(resolve, 10)); // Slow processing
+        console.log(`processed chunk ${chunk} in stream 1`);
+        return chunk; // Fast processing
+      },
+    });
+    const stream2 = new SmartDuplex({
+      name: 'stream2',
+      objectMode: true,
+      writeFunction: async (chunk, tools) => {
+        await new Promise((resolve) => setTimeout(resolve, 20)); // Slow processing
+        console.log(`processed chunk ${chunk} in stream 2`);
+        await tools.push(chunk);
+        // return chunk, optionally return ;
+      },
+    }); // This stream processes data more slowly
+    const stream3 = new SmartDuplex({
+      objectMode: true,
+      name: 'stream3',
+      writeFunction: async (chunk, tools) => {
+        await new Promise((resolve) => setTimeout(resolve, 200)); // Slow processing
+        console.log(`processed chunk ${chunk} in stream 3`);
+      },
+    });
+
+    stream1.pipe(stream2).pipe(stream3);
+
+    let backpressured = false;
+    for (let i = 0; i < 200; i++) {
+      const canContinue = stream1.write(`Chunk ${i}`, 'utf8');
+      if (!canContinue) {
+        backpressured = true;
+        console.log(`Backpressure at chunk ${i}`);
+      }
+    }
+
+    stream1.end();
+
+    stream1.on('finish', () => {
+      console.log('Stream 1 finished processing.');
+    });
+    stream2.on('finish', () => {
+      console.log('Stream 2 finished processing.');
+    });
+    stream3.on('finish', () => {
+      console.log('Stream 3 finished processing.');
+      if (!backpressured) {
+        throw new Error('No backpressure was observed.');
+      } else {
+        done.resolve();
+      }
+    });
+  }
+
+  testBackpressure();
+  await done.promise;
+});
+
+await tap.start();

test/test.smartstream.ts

@@ -5,7 +5,7 @@ import * as fs from 'fs';
 
 tap.test('should create a SmartStream from a Buffer', async () => {
   const bufferData = Buffer.from('This is a test buffer');
-  const smartStream = SmartDuplex.fromBuffer(bufferData);
+  const smartStream = SmartDuplex.fromBuffer(bufferData, {});
   
   let receivedData = Buffer.alloc(0);
   
@@ -21,24 +21,4 @@ tap.test('should create a SmartStream from a Buffer', async () => {
   });
 });
 
-tap.test('should create a SmartStream from an Observable', async () => {
-  const observableData = 'Observable test data';
-  const testObservable = smartrx.rxjs.of(Buffer.from(observableData));
-  
-  const smartStream = SmartDuplex.fromObservable(testObservable);
-  
-  let receivedData = Buffer.alloc(0);
-
-  return new Promise<void>((resolve) => {
-    smartStream.on('data', (chunk: Buffer) => {
-      receivedData = Buffer.concat([receivedData, chunk]);
-    });
-
-    smartStream.on('end', () => {
-      expect(receivedData.toString()).toEqual(observableData);
-      resolve();
-    });
-  });
-});
-
 tap.start();

test/test.streamfunction.ts

@@ -10,7 +10,7 @@ tap.test('should handle a read stream', async (tools) => {
   const streamWrapper = new smartstream.StreamWrapper([
     smartfile.fsStream.createReadStream('./test/assets/readabletext.txt'),
     new smartstream.SmartDuplex({
-      writeAndTransformFunction: async (chunkStringArg: Buffer, streamTools) => {
+      writeFunction: async (chunkStringArg: Buffer, streamTools) => {
         // do something with the stream here
         const result = chunkStringArg.toString().substr(0, 100);
         streamTools.push('wow =========== \n');
@@ -21,7 +21,7 @@ tap.test('should handle a read stream', async (tools) => {
       },
     }),
     new smartstream.SmartDuplex({
-      writeAndTransformFunction: async (chunkStringArg) => {
+      writeFunction: async (chunkStringArg) => {
         console.log(chunkStringArg.toString());
       },
       finalFunction: async (tools) => {
@@ -29,7 +29,7 @@ tap.test('should handle a read stream', async (tools) => {
       },
     })
   ]);
-  // await streamWrapper.run();
+  await streamWrapper.run();
 });
 
 tap.test('should create a valid Intake', async (tools) => {
@@ -37,7 +37,7 @@ tap.test('should create a valid Intake', async (tools) => {
   testIntake.pipe(
       new smartstream.SmartDuplex({
         objectMode: true,
-        writeAndTransformFunction: async (chunkStringArg: string, streamTools) => {
+        writeFunction: async (chunkStringArg: string, streamTools) => {
           await tools.delayFor(100);
           console.log(chunkStringArg);
           return chunkStringArg;

ts/00_commitinfo_data.ts

@@ -3,6 +3,6 @@
  */
 export const commitinfo = {
   name: '@push.rocks/smartstream',
-  version: '3.0.6',
+  version: '3.0.35',
   description: 'simplifies access to node streams'
 }

ts/index.ts

@@ -1,6 +1,8 @@
-export * from './smartstream.classes.passthrough.js';
 export * from './smartstream.classes.smartduplex.js';
 export * from './smartstream.classes.streamwrapper.js';
 export * from './smartstream.classes.streamintake.js';
 
-export * from './smartstream.functions.js'
+export * from './smartstream.functions.js';
+
+import * as plugins from './smartstream.plugins.js';
+export const webstream = plugins.webstream;

ts/smartstream.classes.passthrough.ts

@@ -1,19 +0,0 @@
-import * as plugins from './smartstream.plugins.js';
-
-export class PassThrough extends plugins.stream.Duplex {
-  constructor(options?: plugins.stream.DuplexOptions) {
-    super(options);
-  }
-
-  _read(size: number): void {
-    // No-op: Data written will be automatically available for reading.
-  }
-
-  _write(chunk: any, encoding: BufferEncoding, callback: (error?: Error | null) => void): void {
-    if (this.push(chunk, encoding)) {
-      callback();
-    } else {
-      this.once('drain', callback);
-    }
-  }
-}

ts/smartstream.classes.smartduplex.ts

@@ -3,175 +3,158 @@ import { Duplex, type DuplexOptions } from 'stream';
 
 export interface IStreamTools {
   truncate: () => void;
-  push: (pipeObject: any) => void;
+  push: (pipeObject: any) => Promise<boolean>;
 }
 
-export interface IWriteAndTransformFunction<T, rT> {
+export interface IStreamWriteFunction<T, rT> {
   (chunkArg: T, toolsArg: IStreamTools): Promise<rT>;
 }
 
-export interface IStreamEndFunction<rT> {
+export interface IStreamFinalFunction<rT> {
   (toolsArg: IStreamTools): Promise<rT>;
 }
 
-export interface SmartStreamOptions<TInput, TOutput> extends DuplexOptions {
+export interface ISmartDuplexOptions<TInput, TOutput> extends DuplexOptions {
+  /**
+   * wether to print debug logs
+   */
+  debug?: boolean;
+  /**
+   * the name of the stream
+   */
+  name?: string;
+  /**
+   * a function that is being called to read more stuff from whereever to be processed by the stream
+   * @returns
+   */
   readFunction?: () => Promise<void>;
-  writeAndTransformFunction?: IWriteAndTransformFunction<TInput, TOutput>;
-  finalFunction?: IStreamEndFunction<TOutput>;
-  // Add other custom options if necessary
+
+  /**
+   * the write function is called for every chunk that is being written to the stream
+   * it can push or return chunks (but does not have to) to be written to the readable side of the stream
+   */
+  writeFunction?: IStreamWriteFunction<TInput, TOutput>;
+  
+  /**
+   * a final function that is run at the end of the stream 
+   */
+  finalFunction?: IStreamFinalFunction<TOutput>;
 }
 
 export class SmartDuplex<TInput = any, TOutput = any> extends Duplex {
   // STATIC
-  static fromBuffer(buffer: Buffer, options?: DuplexOptions): SmartDuplex {
-    const smartStream = new SmartDuplex(options);
+  static fromBuffer(buffer: Buffer, options?: ISmartDuplexOptions<any, any>): SmartDuplex {
+    const smartDuplex = new SmartDuplex(options);
     process.nextTick(() => {
-      smartStream.push(buffer);
-      smartStream.push(null); // Signal the end of the data
+      smartDuplex.push(buffer);
+      smartDuplex.push(null); // Signal the end of the data
     });
-    return smartStream;
-  }
-
-  static fromObservable(
-    observable: plugins.smartrx.rxjs.Observable<any>,
-    options?: DuplexOptions
-  ): SmartDuplex {
-    const smartStream = new SmartDuplex(options);
-    smartStream.observableSubscription = observable.subscribe({
-      next: (data) => {
-        if (!smartStream.push(data)) {
-          // Pause the observable if the stream buffer is full
-          smartStream.observableSubscription?.unsubscribe();
-          smartStream.once('drain', () => {
-            // Resume the observable when the stream buffer is drained
-            smartStream.observableSubscription?.unsubscribe();
-            smartStream.observableSubscription = observable.subscribe((data) => {
-              smartStream.push(data);
-            });
-          });
-        }
-      },
-      error: (err) => {
-        smartStream.emit('error', err);
-      },
-      complete: () => {
-        smartStream.push(null); // Signal the end of the data
-      },
-    });
-
-    return smartStream;
-  }
-
-  static fromReplaySubject(
-    replaySubject: plugins.smartrx.rxjs.ReplaySubject<any>,
-    options?: DuplexOptions
-  ): SmartDuplex {
-    const smartStream = new SmartDuplex(options);
-    let isBackpressured = false;
-
-    // Subscribe to the ReplaySubject
-    const subscription = replaySubject.subscribe({
-      next: (data) => {
-        const canPush = smartStream.push(data);
-        if (!canPush) {
-          // If push returns false, pause the subscription because of backpressure
-          isBackpressured = true;
-          subscription.unsubscribe();
-        }
-      },
-      error: (err) => {
-        smartStream.emit('error', err);
-      },
-      complete: () => {
-        smartStream.push(null); // End the stream when the ReplaySubject completes
-      },
-    });
-
-    // Listen for 'drain' event to resume the subscription if it was paused
-    smartStream.on('drain', () => {
-      if (isBackpressured) {
-        isBackpressured = false;
-        // Resubscribe to the ReplaySubject since we previously paused
-        smartStream.observableSubscription = replaySubject.subscribe({
-          next: (data) => {
-            if (!smartStream.push(data)) {
-              smartStream.observableSubscription?.unsubscribe();
-              isBackpressured = true;
-            }
-          },
-          // No need to repeat error and complete handling here because it's already set up above
-        });
-      }
-    });
-
-    return smartStream;
+    return smartDuplex;
   }
 
   // INSTANCE
-  private readFunction?: () => Promise<void>;
-  private writeAndTransformFunction?: IWriteAndTransformFunction<TInput, TOutput>;
-  private streamEndFunction?: IStreamEndFunction<TOutput>;
+  private backpressuredArray: plugins.lik.BackpressuredArray<TOutput>;
+  public options: ISmartDuplexOptions<TInput, TOutput>;
   private observableSubscription?: plugins.smartrx.rxjs.Subscription;
+  private debugLog(messageArg: string) {
+    if (this.options.debug) {
+      console.log(messageArg);
+    }
+  }
 
-  constructor(optionsArg?: SmartStreamOptions<TInput, TOutput>) {
-    super(optionsArg);
-    this.readFunction = optionsArg?.readFunction;
-    this.writeAndTransformFunction = optionsArg?.writeAndTransformFunction;
-    this.streamEndFunction = optionsArg?.finalFunction;
+  constructor(optionsArg?: ISmartDuplexOptions<TInput, TOutput>) {
+    super(Object.assign({
+      highWaterMark: 1,
+    }, optionsArg));
+    this.options = optionsArg;
+    this.backpressuredArray = new plugins.lik.BackpressuredArray<TOutput>(this.options.highWaterMark || 1)
   }
 
   public async _read(size: number): Promise<void> {
-    if (this.readFunction) {
-      await this.readFunction();
+    this.debugLog(`${this.options.name}: read was called`);
+    await this.backpressuredArray.waitForItems();
+    this.debugLog(`${this.options.name}: successfully waited for items.`);
+    if (this.options.readFunction) {
+      await this.options.readFunction();
+    }
+    let canPushMore = true; 
+    while(this.backpressuredArray.data.length > 0 && canPushMore) {
+      const nextChunk = this.backpressuredArray.shift();
+      canPushMore = this.push(nextChunk);
     }
   }
 
+  public async backpressuredPush (pushArg: TOutput) {
+    const canPushMore = this.backpressuredArray.push(pushArg);
+    if (!canPushMore) {
+      this.debugLog(`${this.options.name}: cannot push more`);
+      await this.backpressuredArray.waitForSpace();
+      this.debugLog(`${this.options.name}: can push more again`);
+    }
+    return canPushMore;
+  };
+
+  private asyncWritePromiseObjectmap = new plugins.lik.ObjectMap<Promise<any>>();
   // Ensure the _write method types the chunk as TInput and encodes TOutput
   public async _write(chunk: TInput, encoding: string, callback: (error?: Error | null) => void) {
-    if (!this.writeAndTransformFunction) {
+    if (!this.options.writeFunction) {
       return callback(new Error('No stream function provided'));
     }
 
+    let isTruncated = false;
     const tools: IStreamTools = {
       truncate: () => {
         this.push(null);
+        isTruncated = true;
         callback();
       },
-      push: (pushArg: TOutput) => this.push(pushArg),
+      push: async (pushArg: TOutput) => {
+        return await this.backpressuredPush(pushArg);
+      }
     };
 
     try {
-      const modifiedChunk = await this.writeAndTransformFunction(chunk, tools);
-      if (modifiedChunk) {
-        if (!this.push(modifiedChunk)) {
-          // Handle backpressure if necessary
+      const writeDeferred = plugins.smartpromise.defer();
+      this.asyncWritePromiseObjectmap.add(writeDeferred.promise);
+      const modifiedChunk = await this.options.writeFunction(chunk, tools);
+      if (isTruncated) {
+        return;
       }
+      if (modifiedChunk) {
+        await tools.push(modifiedChunk);
       }
       callback();
+      writeDeferred.resolve();
+      writeDeferred.promise.then(() => {
+        this.asyncWritePromiseObjectmap.remove(writeDeferred.promise);
+      });
     } catch (err) {
       callback(err);
     }
   }
 
   public async _final(callback: (error?: Error | null) => void) {
-    if (this.streamEndFunction) {
+    await Promise.all(this.asyncWritePromiseObjectmap.getArray());
+    if (this.options.finalFunction) {
       const tools: IStreamTools = {
         truncate: () => callback(),
-        push: (pipeObject) => this.push(pipeObject),
+        push: async (pipeObject) => {
+          return this.backpressuredArray.push(pipeObject);
+        },
       };
 
       try {
-        const finalChunk = await this.streamEndFunction(tools);
+        const finalChunk = await this.options.finalFunction(tools);
         if (finalChunk) {
-          this.push(finalChunk);
+          this.backpressuredArray.push(finalChunk);
         }
-        callback();
       } catch (err) {
+        this.backpressuredArray.push(null);
         callback(err);
+        return;
       }
-    } else {
-      this.push(null),
+    }
+    this.backpressuredArray.push(null);
     callback();
   }
 }
-}

ts/smartstream.functions.ts

@@ -1,4 +1,5 @@
 import { Transform, type TransformCallback, type TransformOptions } from 'stream';
+import { SmartDuplex } from './smartstream.classes.smartduplex.js';
 
 export interface AsyncTransformFunction<TInput, TOutput> {
   (chunkArg: TInput): Promise<TOutput>;
@@ -7,20 +8,23 @@ export interface AsyncTransformFunction<TInput, TOutput> {
 export function createTransformFunction<TInput, TOutput>(
   asyncFunction: AsyncTransformFunction<TInput, TOutput>,
   options?: TransformOptions
-): Transform {
-  const transformStream = new Transform({
+): SmartDuplex {
+  const smartDuplexStream = new SmartDuplex({
     ...options,
-    objectMode: true, // Ensure we operate in object mode
-    async transform(chunk: TInput, encoding: string, callback: TransformCallback) {
-      try {
-        const transformed = await asyncFunction(chunk);
-        this.push(transformed);
-        callback();
-      } catch (error) {
-        callback(error instanceof Error ? error : new Error(String(error)));
-      }
+    writeFunction: async (chunkArg, toolsArg) => {
+      const result = await asyncFunction(chunkArg);
+      return result;
     }
   });
 
-  return transformStream;
+  return smartDuplexStream;
+}
+
+export const createPassThrough = () => {
+  return new SmartDuplex({
+    objectMode: true,
+    writeFunction: async (chunkArg, toolsArg) => {
+      return chunkArg;
+    }
+  })
 }

ts/smartstream.plugins.ts

@@ -4,8 +4,10 @@ import * as stream from 'stream';
 export { stream };
 
 // pushrocks scope
+import * as lik from '@push.rocks/lik';
 import * as smartpromise from '@push.rocks/smartpromise';
 import * as smartrx from '@push.rocks/smartrx';
+import * as webstream from '@push.rocks/webstream';
 
-export { smartpromise, smartrx };
+export { lik, smartpromise, smartrx, webstream };