Sunday, October 18, 2020

Grails on Groovy - Clear and Flush Current Hibernate Session Data and Evict All Query Cache Data | Clearing Hibernate Query Cache in Grails

Hibernate already has support for query cache. And we know that when we perform a big task there are huge number queries remain in our cache factory. And more important that in most cases we don't need this caches so as a result cache factory getting full with unusual cache data.
This could be a performance issue - so it's better we clear cache on our own responsibility after a big task completed.
Below are the procedure to flush and clear current session (hibernate session) data so that cache factory have enough space for further execution.
import org.hibernate.SessionFactory
import grails.util.Holders

private static SessionFactory _sessionFactory

static Boolean flushAndClearCache() {
    try {
        sessionFactory.currentSession.flush()
        sessionFactory.currentSession.clear()
        sessionFactory.getCache().evictEntityRegions()
        sessionFactory.getCache().evictCollectionRegions()
        sessionFactory.getCache().evictDefaultQueryRegion()
        sessionFactory.getCache().evictQueryRegions()
        return true
    }
    catch (Throwable ex) {
        log.error(ex.ex)
        return false
    }
}

static <T> T getBean(Class<T> requiredType) {
    try {
        return Holders.applicationContext.getBean(requiredType)
    }
    catch (Throwable e) {
        return null
    }
}

static SessionFactory getSessionFactory() {
    _sessionFactory = _sessionFactory ?: (_sessionFactory = getBean(SessionFactory))
}

Sunday, July 12, 2020

How to remove build files before another new build start on Laravel-Mix Webpack config file | Delete unused laravel chunk files | Clean dist folder before generating a new build - Laravel with ReactJS

Since we generate lot of builds with different hashed filenames, it is a good practice to delete the dist directory before running each build.
In laravel-mix webpack.mix.js is the configuration file we used for reactjs webpack configuration. What we have to do write some code to webpack.mix.js (located in based directory of project in my case)
const mix = require('laravel-mix');
const date = (new Date()).getTime();

const fs = require('fs');
const buildDir = './public/js/chunk/';
fs.readdir(path.resolve(buildDir), (err, files) => {
    if (err) {
        console.log(err);
    }
    else {
        files.forEach(function (file) {
            fs.unlink(path.resolve(buildDir + file), function () {
                console.log(buildDir + file + ' - deleted');
            });
        });
    }
});

/*
 |--------------------------------------------------------------------------
 | Mix Asset Management
 |--------------------------------------------------------------------------
 |
 | Mix provides a clean, fluent API for defining some Webpack build steps
 | for your Laravel application. By default, we are compiling the Sass
 | file for the application as well as bundling up all the JS files.
 |
 */

mix.react('resources/js/app.js', 'public/js')
   .sass('resources/sass/app.scss', 'public/css');

mix.webpackConfig({
    output: {
        // Directory for junk files to {ROOT_DIR}/public/js
        chunkFilename: 'js/chunk/[name]-' + date + '.js'
    },
});

Thursday, April 30, 2020

How to save Username and Password in GIT Bash

First Run Below Command From GIT Bash (Remove --global if you want to save credentials for current project only)


git config --global credential.helper store
Now run below command and provide username/password (which will be remembered)
git pull
Provide a username and password and those details will then be remembered later. The credentials are stored in a file on the disk, with the disk permissions of "just user readable/writable" but still in plaintext.

Friday, April 17, 2020

Firebase Authentication for Web - Sign-in Method Email/Password Implementation

First go to https://firebase.google.com/docs/web/setup and create a project step by step by following https://console.firebase.google.com/.

Step 2: Register your app with Firebase

Go to https://console.firebase.google.com/u/0/project/test-firebase-auth-1/authentication/providers for enable signin method.

I enabled Email/Password authentication type for this example.

To initialize Firebase in your app, you need to provide your app's Firebase project configuration.

Go to Project Settings page for configure app and get API Key.



Step 3: Add Firebase SDKs and initialize Firebase, we will use CDN to load all necessary resources

<script src="//www.gstatic.com/firebasejs/7.14.0/firebase-app.js"></script>
<script src="//www.gstatic.com/firebasejs/7.8.1/firebase-auth.js"></script>

<script type="text/javascript">
    $(document).ready(function () {
        // Your web app's Firebase configuration
        var firebaseConfig = {
            apiKey: "AIzaSyA9XqTsdfsdfsdf0w9TSlYSlUlpCLcNjeM",
            authDomain: "test-firebase-auth-1.firebaseapp.com",
            databaseURL: "https://test-firebase-auth-1.firebaseio.com",
            projectId: "test-firebase-auth-1",
            storageBucket: "test-firebase-auth-1.appspot.com",
            messagingSenderId: "514502059460",
            appId: "1:51450324232059460:web:70b12cd2342345ee4287f932f091"
        };
        // Initialize Firebase
        var defaultProject = firebase.initializeApp(firebaseConfig);

        console.log(defaultProject.auth());
    });
</script>
You can restrict your API Key to specific domain using below steps:

1. Visit https://console.developers.google.com/apis
2. Go to your firebase project
3. Go to Credentials
4. Under API keys, select the Browser key associated with your firebase project (should have the same key as the API key you use to initialize your firebase app.)
5. Under "Accept requests from these HTTP referrers (web sites), simply add the URL of your app.



We are done from configure Firebase.

Now we will build our registration/login page.

Request Sample When User State Changed (Login,Logout,Registration)


defaultProject.auth().onAuthStateChanged(function(user) {
    if (user) {
        console.log("Logged in user details");
        console.log(user);

        console.log(user.displayName);
        console.log(user.email);
    }
    else {
        window.location.href = "/";
    }
});

Request Sample to Register User With Email/Password


defaultProject.auth().createUserWithEmailAndPassword(email, password).catch(function(error) {
    console.log(error);
    if (error.message) {
        alert(error.message);
    }
});

Request Sample to Login Action


defaultProject.auth().signInWithEmailAndPassword(email, password).catch(function(error) {
    console.log(error);
    if (error.message) {
        alert(error.message);
    }
});

Password Reset Email Send Request

defaultProject.auth().sendPasswordResetEmail(email).then(function() {
    alert('Password Reset Email Sent!');
}).catch(function(error) {
    console.log(error);
    if (error.message) {
        alert(error.message);
    }
});

You can configure password reset URL



You can reset your password using below code snippet

const queryString = window.location.search;

const urlParams = new URLSearchParams(queryString);

const code = urlParams.get('oobCode');

defaultProject.auth().confirmPasswordReset(code, "Password-123456").then(function() {
    alert('Password Reset Completed');
}).catch(function(error) {
    console.log(error);
    if (error.message) {
        alert(error.message);
    }
});
Finally GibHUB link to the sample project


Saturday, March 14, 2020

Laravel-mix Webpack Public Path | Set custom path for chunk files | Using Laravel Mix with webpack for All Your Assets

Laravel Mix allows you to use a single line to describe what you want and it'll use it's preconfigured settings to process it properly.
Most of our time will be spent in the webpack.mix.js file. In the file, we can configure all we need to do to set public path and we can also set js file location for chunk js files when we use Suspense and lazy for dynamic js loading for per route.
There are several more Mix methods and you can set all of them in the default webpack.mix.js file.
// Full API
    // mix.js(src, output);
    // mix.react(src, output); <-- Identical to mix.js(), but registers React Babel compilation.
    // mix.extract(vendorLibs);
    // mix.sass(src, output);
    // mix.standaloneSass('src', output); <-- Faster, but isolated from Webpack.
    // mix.fastSass('src', output); <-- Alias for mix.standaloneSass().
    // mix.less(src, output);
    // mix.stylus(src, output);
    // mix.postCss(src, output, [require('postcss-some-plugin')()]);
    // mix.browserSync('my-site.dev');
    // mix.combine(files, destination);
    // mix.babel(files, destination); <-- Identical to mix.combine(), but also includes Babel compilation.
    // mix.copy(from, to);
    // mix.copyDirectory(fromDir, toDir);
    // mix.minify(file);
    // mix.sourceMaps(); // Enable sourcemaps
    // mix.version(); // Enable versioning.
    // mix.disableNotifications();
    // mix.setPublicPath('path/to/public');
    // mix.setResourceRoot('prefix/for/resource/locators');
    // mix.autoload({}); <-- Will be passed to Webpack's ProvidePlugin.
    // mix.webpackConfig({}); <-- Override webpack.config.js, without editing the file directly.
    // mix.then(function () {}) <-- Will be triggered each time Webpack finishes building.
    // mix.options({
    //   extractVueStyles: false, // Extract .vue component styling to file, rather than inline.
    //   processCssUrls: true, // Process/optimize relative stylesheet url()'s. Set to false, if you don't want them touched.
    //   purifyCss: false, // Remove unused CSS selectors.
    //   uglify: {}, // Uglify-specific options. https://webpack.github.io/docs/list-of-plugins.html#uglifyjsplugin
    //   postCss: [] // Post-CSS options: https://github.com/postcss/postcss/blob/master/docs/plugins.md
    // });
Below is the code snippet which will define js file location for chunk js files:
const mix = require('laravel-mix');

/*
 |--------------------------------------------------------------------------
 | Mix Asset Management
 |--------------------------------------------------------------------------
 |
 | Mix provides a clean, fluent API for defining some Webpack build steps
 | for your Laravel application. By default, we are compiling the Sass
 | file for the application as well as bundling up all the JS files.
 |
 */

mix.react('resources/js/app.js', 'public/js')
   .sass('resources/sass/app.scss', 'public/css');

mix.webpackConfig({
    output: {
        // Directory for junk files to {ROOT_DIR}/public/js
        chunkFilename: 'js/[name].js',
    },
});

Thursday, March 12, 2020

React Component on Window Resize Event

React doesn't have a resize event integrated into it, but we can listen to the native browser window resize event from within our React component. We will attach window resize event into componentDidMount method.
Under normal conditions, React will re-render a component when its props or state changes. To trigger a re-render of Component in the example, we'll set internal state on the component when the event is fired. So we can set/update state variable to tell React Component to update. We can implement method componentDidUpdate to acknoledged something changed.
When adding an event listener, such as we are for the resize event, we should make sure to clean up after ourselves. We will clean up any type of listener we added into method componentWillUnmount.
Example code given below:
import React from "react";
import "./styles.css";

class App extends React.Component {
  constructor() {
    super();

    // we will update below state variables to tell react component
    // to update, only state or props change can update react component
    this.state = {
      width: 0,
      height: 0
    };

    // we will use this timer to less fire resize event
    // practially we will fire resize event 500 miliseconds after
    this.timer = null;

    // we will catch windows resize event into below function
    this.windowResized = this.windowResized.bind(this);

    // we will handle resize event so resize event will
    // be in some time interval, less freequent 
    this.updateWindowWidth = this.updateWindowWidth.bind(this);
  }

  componentDidMount() {
    window.addEventListener("resize", this.windowResized);
    this.updateWindowWidth();
  }

  componentDidUpdate() {
    console.log(
      `Window width/height changed to ${this.state.width}X${this.state.height}`
    );
  }

  componentWillUnmount() {
    window.removeEventListener("resize", this.windowResized);
  }

  updateWindowWidth() {
    let _this = this;
    setTimeout(function() {
      _this.setState({
        width: window.innerWidth,
        height: window.innerHeight
      });
    });
  }

  windowResized() {
    let _this = this;
    if (this.timer) {
      clearTimeout(this.timer);
    }
    this.timer = setTimeout(function() {
      _this.updateWindowWidth();
    }, 500);
  }

  render() {
    return (
      <div className="App">
        <h1>
          WIDTH={this.state.width} HEIGHT={this.state.height}
        </h1>
      </div>
    );
  }
}

export default App;
Sample Image:

Live Example:

https://codesandbox.io/s/react-component-on-window-resize-event-3b29u

Saturday, March 7, 2020

Lazy Loading React Components (with react.lazy and suspense)

Our first step is to create an React application using below command:

npm init react-app react-lazy-loading-component

Navigate to project folder and type npm start to start project on browser.

Make sure you execute command npm run build to prepare build script which will be deployed on server

Route-based code splitting

You have to install react-router-dom using npm install --save react-router-dom to use this functionality.

Deciding where in your app to introduce code splitting can be a bit tricky. You want to make sure you choose places that will split bundles evenly, but won’t disrupt the user experience.

A good place to start is with routes. Most people on the web are used to page transitions taking some amount of time to load. You also tend to be re-rendering the entire page at once so your users are unlikely to be interacting with other elements on the page at the same time.
Sample App.js

import {BrowserRouter as Router, Route, Switch} from 'react-router-dom';
import React, {Suspense, lazy} from 'react';
import './App.css';

import Header from './Header';

const Home = lazy(() => import('./Home'));
const AnotherHome = lazy(() => import('./AnotherHome'));

function App() {
    return (
        <div>
            <Router>
                <Header/>
                <div className="container">
                    <Suspense fallback={<div>Loading...</div>}>
                        <Switch>
                            <Route exact path="/" component={Home}/>
                            <Route exact path="/another-home" component={AnotherHome}/>
                        </Switch>
                    </Suspense>
                </div>
            </Router>
        </div>
    );
}

export default App;
Actually use of Suspense and Lazy will load components chunk by chunk when they needed, and once a component loaded into browser will not load second time.
GitHub Link https://github.com/pritomkucse/react-lazy-loading-component
Live Example at codesandbox.io

https://codesandbox.io/s/lazy-loading-react-components-with-reactlazy-and-suspense-2hx75

Make sure you see console to ensure that suspense callback working as expected: