chore: working on chapter 6

06-coding-with-streams/05-readabl-flowing/package.json → 06-coding-with-streams/05-readable-flowing/package.json

@@ -1,5 +1,5 @@
 {
-  "name": "05-readabl-flowing",
+  "name": "05-readable-flowing",
   "version": "1.0.0",
   "description": "This example shows how to consume a readable stream in flowing mode.",
   "type": "module",

06-coding-with-streams/06-readable-async-iterator/README.md

@@ -0,0 +1,23 @@
+# 06-readable-async-iterator
+
+This examples shows how to consume a readable stream using the async iterator
+interface.
+
+## Run
+
+To run the example you can use:
+
+```bash
+node read-stdin.js
+```
+
+Now write in the standard input and use `ctrl+d` (unix) or `ctrl+z` (windows) to
+end the input stream.
+
+Alternatively:
+
+```bash
+cat <path_of_file> | node read-stdin.js
+```
+
+to consume an arbitrary file.

06-coding-with-streams/06-readable-async-iterator/package.json

@@ -0,0 +1,15 @@
+{
+  "name": "06-readable-async-iterator",
+  "version": "1.0.0",
+  "description": "This examples shows how to consume a readable stream using the async iterator interface.",
+  "type": "module",
+  "scripts": {},
+  "engines": {
+    "node": ">=22"
+  },
+  "engineStrict": true,
+  "keywords": [],
+  "author": "Luciano Mammino and Mario Casciaro",
+  "license": "MIT",
+  "dependencies": {}
+}

06-coding-with-streams/06-readable-async-iterator/read-stdin.js

@@ -0,0 +1,6 @@
+for await (const chunk of process.stdin) {
+  console.log('New data available')
+  console.log(`Chunk read (${chunk.length} bytes): "${chunk.toString()}"`)
+}
+
+console.log('End of stream')

06-coding-with-streams/07-custom-readable/README.md

@@ -0,0 +1,25 @@
+# 07-custom-readable
+
+This example shows how to implement a custom Readable stream.
+
+## Dependencies
+
+Install all necessary dependencies with:
+
+```bash
+npm install
+```
+
+## Run
+
+To run the example you can run:
+
+```bash
+node index.js
+```
+
+or:
+
+```bash
+node simplified-construction.js
+```

06-coding-with-streams/07-custom-readable/index.js

@@ -0,0 +1,10 @@
+import { RandomStream } from './random-stream.js'
+
+const randomStream = new RandomStream()
+randomStream
+  .on('data', chunk => {
+    console.log(`Chunk received (${chunk.length} bytes): ${chunk.toString()}`)
+  })
+  .on('end', () => {
+    console.log(`Produced ${randomStream.emittedBytes} bytes of random data`)
+  })

06-coding-with-streams/07-custom-readable/package.json

@@ -0,0 +1,17 @@
+{
+  "name": "07-custom-readable",
+  "version": "1.0.0",
+  "description": "This example shows how to implement a custom Readable stream.",
+  "type": "module",
+  "scripts": {},
+  "engines": {
+    "node": ">=22"
+  },
+  "engineStrict": true,
+  "keywords": [],
+  "author": "Luciano Mammino and Mario Casciaro",
+  "license": "MIT",
+  "dependencies": {
+    "chance": "^1.1.12"
+  }
+}

06-coding-with-streams/07-custom-readable/random-stream.js

@@ -0,0 +1,20 @@
+import { Readable } from 'node:stream'
+import Chance from 'chance' // v1.1.12
+
+const chance = new Chance()
+
+export class RandomStream extends Readable {
+  constructor(options) {
+    super(options)
+    this.emittedBytes = 0
+  }
+
+  _read(size) {
+    const chunk = chance.string({ length: size })
+    this.push(chunk, 'utf8')
+    this.emittedBytes += chunk.length
+    if (chance.bool({ likelihood: 5 })) {
+      this.push(null)
+    }
+  }
+}

06-coding-with-streams/07-custom-readable/simplified-construction.js

@@ -0,0 +1,24 @@
+import { Readable } from 'node:stream'
+import Chance from 'chance' // v1.1.12
+
+const chance = new Chance()
+let emittedBytes = 0
+
+const randomStream = new Readable({
+  read(size) {
+    const chunk = chance.string({ length: size })
+    this.push(chunk, 'utf8')
+    emittedBytes += chunk.length
+    if (chance.bool({ likelihood: 5 })) {
+      this.push(null)
+    }
+  },
+})
+
+randomStream
+  .on('data', chunk => {
+    console.log(`Chunk received (${chunk.length} bytes): ${chunk.toString()}`)
+  })
+  .on('end', () => {
+    console.log(`Produced ${emittedBytes} bytes of random data`)
+  })

06-coding-with-streams/08-custom-readable-from-iterable/README.md

@@ -0,0 +1,12 @@
+# 08-custom-readable-from-iterable
+
+This example shows how to implement a custom Readable stream using
+`Readable.from`.
+
+## Run
+
+To run the example you can run:
+
+```bash
+node index.js
+```

06-coding-with-streams/08-custom-readable-from-iterable/index.js

@@ -0,0 +1,14 @@
+import { Readable } from 'node:stream'
+
+const mountains = [
+  { name: 'Everest', height: 8848 },
+  { name: 'K2', height: 8611 },
+  { name: 'Kangchenjunga', height: 8586 },
+  { name: 'Lhotse', height: 8516 },
+  { name: 'Makalu', height: 8481 },
+]
+
+const mountainsStream = Readable.from(mountains)
+mountainsStream.on('data', mountain => {
+  console.log(`${mountain.name.padStart(14)}\t${mountain.height}m`)
+})

06-coding-with-streams/08-custom-readable-from-iterable/package.json

@@ -0,0 +1,15 @@
+{
+  "name": "08-custom-readable-from-iterable",
+  "version": "1.0.0",
+  "description": "This example shows how to implement a custom Readable stream using `Readable.from`.",
+  "type": "module",
+  "scripts": {},
+  "engines": {
+    "node": ">=22"
+  },
+  "engineStrict": true,
+  "keywords": [],
+  "author": "Luciano Mammino and Mario Casciaro",
+  "license": "MIT",
+  "dependencies": {}
+}

06-coding-with-streams/09-writable-http-entropy-server/README.md

@@ -0,0 +1,27 @@
+# 09-writable-http-entropy-server
+
+This example shows how to write into a readable stream, specifically an HTTP
+response sent by a server.
+
+## Dependencies
+
+Install all necessary dependencies with:
+
+```bash
+npm install
+```
+
+## Run
+
+To run the server:
+
+```bash
+node entropy-server.js
+```
+
+Now you can make requests to the server by pointing your browser to
+[http://localhost:3000] or with curl as follows:
+
+```bash
+curl -i -vvv http://localhost:3000/
+```

06-coding-with-streams/09-writable-http-entropy-server/entropy-server.js

@@ -0,0 +1,17 @@
+import { createServer } from 'node:http'
+import Chance from 'chance' // 1.1.12
+
+const chance = new Chance()
+
+const server = createServer((_req, res) => {
+  res.writeHead(200, { 'Content-Type': 'text/plain' })
+  do {
+    res.write(`${chance.string()}\n`)
+  } while (chance.bool({ likelihood: 95 }))
+  res.end('\n\n')
+  res.on('finish', () => console.log('All data sent'))
+})
+
+server.listen(3000, () => {
+  console.log('listening on http://localhost:3000')
+})

06-coding-with-streams/09-writable-http-entropy-server/package.json

@@ -0,0 +1,17 @@
+{
+  "name": "09-writable-http-entropy-server",
+  "version": "1.0.0",
+  "description": "This example shows how to write into a readable stream, specifically an HTTP response sent by a server.",
+  "type": "module",
+  "scripts": {},
+  "engines": {
+    "node": ">=22"
+  },
+  "engineStrict": true,
+  "keywords": [],
+  "author": "Luciano Mammino and Mario Casciaro",
+  "license": "MIT",
+  "dependencies": {
+    "chance": "^1.1.12"
+  }
+}