Merge pull request #29 from scramjetorg/fix/bring-back-samples

Bring back deleted samples

Author: MichalCz

samples/hello/README.md

@@ -0,0 +1,60 @@
+## hello 🙋‍♂️
+
+----
+Sequence that modifies incoming stream of strings by saying Hello :).
+
+> :bulb: **Please note that the sample below requires some previous installations before you start running it, you will find them [here](../../README.md#3-install-scramjet-transform-hub).**
+
+### Running
+
+Open three terminals and run the following commands:
+
+**The first terminal:**
+
+```bash
+# start sth
+scramjet-transform-hub
+```
+
+**The second terminal**
+
+```bash
+# go to 'hello' directory
+cd samples/hello
+
+# install dependencies
+npm install
+
+# make a compressed package with sequence
+si pack . -o hello.tar.gz
+
+# send sequence to transform hub, this will output Sequence ID
+si seq send hello.tar.gz
+
+# start a sequence, this will output Instance ID
+si seq start <sequence-id>
+
+# See output of instance process
+si inst output <instance-id>
+```
+
+**The third terminal**
+
+```bash
+# Send file to instance input steam
+si inst input <instance-id> name.txt
+# if file not given the data will be read from stdin
+```
+
+<!-- TODO Delete when the issue is solved
+Issue created for reading data from stdin https://github.com/scramjetorg/transform-hub/issues/165 -------ISSUE SOLVED!!! awaits release
+-->
+
+### Output
+
+```bash
+# Now you should see "Hello John" in output console
+$ si inst output 7a1ffd59-9d1a-4e8f-a246-020124803931
+Request ok: http://127.0.0.1:8000/api/v1/instance/7a1ffd59-9d1a-4e8f-a246-020124803931/output status: 200 OK
+Hello John
+```

samples/hello/index.js

@@ -0,0 +1,10 @@
+const { Transform } = require("stream");
+
+module.exports = function(input) {
+    return input.pipe(new Transform({
+        encoding: "utf-8",
+        transform(chunk, _encoding, callback) {
+            callback(null, `Hello ${chunk}`);
+        }
+    }));
+};

samples/hello/name.txt

@@ -0,0 +1 @@
+John

samples/hello/package.json

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+{
+  "name": "@scramjet/hello",
+  "version": "0.13.1",
+  "description":"Sequence that modifies incoming stream of strings by saying Hello",
+  "main": "./index",
+  "author": "Scramjet <[email protected]>",
+  "license": "GPL-3.0",
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/scramjetorg/transform-hub.git"
+  },
+  "assets": ["name.txt"]
+}

samples/scraping/README.md

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+## scraping
+
+---
+This is a simple and trivial example of scraping web pages.
+
+The scraper takes URL and CSS ID selector as input parameters and returns data every second.
+
+To test this please use URL: <https://www.timeanddate.com/worldclock/poland> and ID: `#ct`. Scraper will connect to the website and read (scrap) the current time. Next, it returns this as a stream.
+As URL and ID are parametrized we can use other websites too. For example, URL: <https://time.is/> and ID: `#clock`
+
+> :bulb: **Please note that the sample below requires some previous installations before you start running it, you will find them [here](../../README.md#3-install-scramjet-transform-hub).**
+
+### Running
+
+Open two terminals and run the following commands:
+
+**The first terminal:**
+
+```bash
+# start sth
+scramjet-transform-hub
+```
+
+**The second terminal**
+
+```bash
+# go to 'scraping' directory
+cd samples/scraping
+
+# install dependencies
+npm install
+
+# transpile TS->JS to dist/
+npm run build
+
+# prepare standalone JS package
+cp -r node_modules package.json dist/
+
+# make a compressed package with sequence
+si pack dist
+
+# send sequence to transform hub, this will output Sequence ID
+si seq send dist.tar.gz
+
+# start a sequence, this will output Instance ID. As the CSS ID has # (hash) sign surround it with quotes:
+si seq start <sequence-id> https://www.timeanddate.com/worldclock/poland '#ct'
+
+# See output
+si inst output <instance-id>
+
+# Optional commands below:
+
+# Check console.log messages
+si inst stdout <instance-id>
+
+# Check console.error messages
+si inst stderr <instance-id>
+```
+
+### Output
+
+```bash
+$ si instance output 41783884-2e97-4b78-9639-aac5d7ff8447
+Request ok: http://127.0.0.1:8000/api/v1/instance/41783884-2e97-4b78-9639-aac5d7ff8447/output status: 200 OK
+13:06:10
+13:06:15
+13:06:20
+13:06:25
+13:06:31
+13:06:36
+13:06:41
+13:06:46
+13:06:51
+13:06:56
+(...)
+```

samples/scraping/app.ts

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+import { ReadableApp } from "@scramjet/types";
+import { scrape } from './scrape'
+import { sleep } from './utils'
+
+const app: ReadableApp<string, [string, string]> = async function* (
+    _stream, 
+    url, 
+    selectorStr,
+    interval = 5000,
+) {
+    while(true) {
+        const timer = sleep(interval);
+        yield await scrape(url, selectorStr) + '\n'
+        
+        await timer;
+    }
+}
+
+export default app;

samples/scraping/package.json

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+{
+  "name": "@scramjet/scraping",
+  "version": "0.13.1",
+  "description": "This is a simple and trivial example of scraping web pages.",
+  "main": "app.js",
+  "scripts": {
+    "build": "tsc -p tsconfig.json"
+  },
+  "author": "Scramjet <[email protected]>",
+  "license": "GPL-3.0",
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/scramjetorg/transform-hub.git"
+  },
+  "dependencies": {
+    "axios": "^0.21.4",
+    "cheerio": "*",
+    "scramjet": "^4.36.0"
+  },
+  "devDependencies": {
+    "@scramjet/types": "^0.13.1",
+    "@types/node": "15.12.5",
+    "typescript": "^4.3.4"
+  }
+}

samples/scraping/scrape.ts

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+import * as cheerio from 'cheerio';
+import axios from 'axios';
+
+export async function scrape(url: string, selectorStr: string) {
+    const html = (await axios.get(url)).data;
+    const $ = cheerio.load(html);
+    const selector = $(selectorStr);
+
+    return selector.text();
+}

samples/scraping/test.ts

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+import { scrap } from './scrap';
+
+const BASE_URL = 'https://time.is/';
+
+(async () => {
+  const result = await scrap(BASE_URL, "#clock");
+  console.log(`RESULT: ${result}`);
+})();

samples/scraping/tsconfig.json

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+{
+  "compilerOptions": {
+    "outDir": "./dist",
+    "esModuleInterop": true,
+    "allowSyntheticDefaultImports": true
+  },
+  "include": [
+    "app.ts"
+  ],
+}