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Published: September 05, 2018 • javascript
The Beacon API in the browser can be used to transfer data to a server. It's primary use case is to send analytics data during the unload event of a web page. In this blog post we will look at the API and create some examples that use the Beacon API to send data to a server.
Published: September 03, 2018 • javascript
A look at the new numeric primitive BigInt in the JavaScript language
Published: July 10, 2018 • linux, selfhosted
In this article I describe how you can install OpenMapTiles, an open source tile server, on our own server
Published: June 26, 2018 • pwa, javascript, java, spring
This blog post takes a closer look at the Background Sync API, part of the Service Worker implementation and presents an example that uses Background Sync to synchronize data between an Ionic 4 web application and a Spring Boot server application.
Published: June 22, 2018 • pwa, javascript
A description how to add a Workbox Service Worker to an Angular project instead of using the Angular Service Worker
Published: June 16, 2018 • linux, selfhosted
In this tutorial I present two ways how to send emails from your self-hosted Linux server. A configuration with SSMTP, that relies on a 3rd party mail server and an example with exim4, a self-hosted SMTP server.
Published: June 12, 2018 • linux, selfhosted
In this tutorial we look at SparkleShare, a self-hosted, instant and secure file synchronization service
Published: June 10, 2018 • linux, selfhosted
How to install a backup job that runs daily and sends files to Amazon S3
Published: June 10, 2018 • Updated: August 28, 2018 • linux, selfhosted
In this tutorial I show you how to install a Gitea Git server, install a http server with a domain and secure the connection with a Let's Encrypt TLS certificate.
Published: June 10, 2018 • linux, selfhosted
A quick introduction to the free Windows SSH client Putty. How you can connect to a SSH server and how to set up public/private key authentication.
Published: June 10, 2018 • linux, selfhosted
A description of initial configuration steps after renting a new VPS server
Published: May 03, 2018 • java, javascript
In this blog post I present four examples how you can implement password checks for commonly used or compromised passwords.
Published: May 01, 2018 • java
How a Java server application can complete the server-to-server OAuth 2.0 flow and access a Google service
Published: March 01, 2018 • java
In this blog post we will create Java applications that download and search the "Have I been pwned?" password list with over 501 million passwords.
Published: February 28, 2018 • java, javascript
In this blog post we create a simple polling application with Java and JavaScript and send real time updates with server-sent events
Published: February 27, 2018 • java, javascript
Writing human readable regular expressions with the VerbalExpression library
Published: February 26, 2018 • java
How to consume Server-sent events in a Java application.
Published: February 14, 2018 • javascript
Two examples how you can conditionally load polyfills in a JavaScript application
Published: February 05, 2018 • database, mongodb, java
A brief introduction to Time to live indexes in MongoDB and how to access them from Java
Published: February 04, 2018 • Updated: February 05, 2018 • mongodb, java, database
A brief overview of capped collections in MongoDB and how to access them from Java
Published: January 15, 2018 • javascript
A short tutorial on how to install Polyfill.io on Ubuntu And an example how you can use Polyfill.io together with Babel
Published: January 13, 2018 • Updated: January 25, 2018 • java, javascript
An example project that integrates a front end JavaScript application with the Parcel bundler and a Spring Boot application built with Maven into one project and ultimately create one executable JAR.
Published: January 12, 2018 • database, javascript
In this blog post I present a way to use Dexie in a TypeScript application
Published: January 12, 2018 • database, javascript
In this blog post I give you an overview about Dexie, a minimalistic wrapper library for IndexedDB. Write simpler and more concise IndexedDB code with Dexie.
Published: January 09, 2018 • pwa, javascript
Explore the provided methods of the Cache API that is primarily used in Service Workers to cache assets, but can be used anywhere as a general purpose cache.
Published: January 09, 2018 • Updated: July 18, 2018 • java, javascript, pwa, spring
In this blog post I show you how you can send push messages from a Spring Boot application over Firebase Cloud Messaging (FCM) to connected clients with the Web Push API. The Push API is part of the Service Worker specification and does not depend on any native plugins.
Published: January 08, 2018 • Updated: January 09, 2018 • javascript
A close look at the date-fns date/time library. Compare it with Moment.js and look at a few examples
Published: January 07, 2018 • Updated: February 16, 2018 • javascript
A close look at Parcel and present various examples how to bundle web applications with technologies like Babel, TypeScript and Sass.
Published: January 06, 2018 • ionic3, javascript
How to use arbitrary SVG icons in an Ionic 3 app
Published: January 06, 2018 • ionic3, javascript
This blog post shows the lifecycle methods of Ionic 3 and when they are called. The second part describes a way how to distinguish between the forward and backward navigation (list and detail page).
Published: December 18, 2017 • Updated: February 16, 2018 • ionic3, javascript, java, spring
In this blog post I present three different way how to integrate a speech recognition functionality into an Ionic 3 app. With a Cordova plugin, the Web Speech API and with RecordRTC and the Google Cloud Speech API.
Published: December 17, 2017 • Updated: April 17, 2018 • ionic3, pwa
How to integrate the service worker library Workbox into an Ionic 3 app with lazy loaded modules
Published: November 07, 2017 • Updated: February 16, 2018 • ionic3, java, spring, javascript
In this blog post we create together a self hosted location tracker that consists of three parts. An Ionic 3/Cordova application that continuously sends the current location to a Spring Boot application from where the locations are broadcasted to a website and visualized with Google Maps.
Published: November 05, 2017 • Updated: April 22, 2018 • pwa, ionic3, javascript
Creating Service Workers with Workbox for Ionic 3 applications
Published: November 05, 2017 • Updated: January 31, 2018 • ionic3, java, spring, javascript
In this blog post we create an Ionic 3 app that dynamically requests location data points from a Spring Boot server and displays them on a OpenStreetMap map. The data points are stored in a MongoDB database and we take advantage of the geospatial query support to read the data points only for a certain area.
Published: October 21, 2017 • Updated: January 17, 2018 • java
The latest Java update changed the way how you enable unlimited cryptography in your Java application.
Published: September 26, 2017 • java, ionic3, javascript, spring
A closer look at the Flow.js JavaScript library that helps uploading files from a browser to the server. Flow.js is a JavaScript library providing multiple simultaneous, stable, fault-tolerant and resumable/restartable file uploads via the HTML5 File API.
Published: September 25, 2017 • Updated: November 16, 2017 • javascript, cryptography
Creating a trivial password manager with the Web Cryptography API and the Ionic 3 framework.
Published: September 21, 2017 • Updated: February 17, 2018 • spring, java, javascript, ionic3
In this blog we create REST services in Spring Boot and consume them in an Ionic 3 app. We use the OpenAPI specification for generating an API documentation and the client TypeScript code.
Published: September 17, 2017 • Updated: February 16, 2018 • java
How to use pluggable file systems in Java and a look at implementations outside the standard library
Published: September 16, 2017 • Updated: October 25, 2017 • java
How to create a simple MultiValue Map with Java 8
Published: September 15, 2017 • Updated: November 16, 2017 • database, javascript, ionic3
Example of an Ionic 3 web application that stores data in an IndexedDB and works offline.
Published: September 12, 2017 • Updated: October 30, 2017 • database, javascript
IndexedDB, the database in the browser. How does it work and what can you do with it.
Published: March 05, 2017 • Updated: February 16, 2018 • java, spring
What are Server-Sent Events and how can you send them from a Spring Boot application
Published: February 27, 2017 • Updated: November 16, 2017 • database, ionic3, javascript
A short introduction to Lovefield, a JavaScript SQL database engine. And how to build an Ionic 3 app that uses Lovefield as database access layer.
Published: February 26, 2017 • Updated: June 11, 2018 • ionic3, spring, javascript, java
This post describes how a Spring Boot can send messages over FCM to an Ionic 3 app
Published: February 22, 2017 • Updated: September 10, 2018 • ionic3, javascript
In this post we look at a way to display charts from the ECharts library in an Ionic 3 app
Published: February 18, 2017 • Updated: March 22, 2018 • ionic3, cryptography
In this post we create a Todo application with Ionic 3 that stores the data encrypted in the client storage. asmcrypto.js will be used as the cryptographic library and we have a look at the Web Crypto API
Published: February 16, 2017 • Updated: February 16, 2018 • ionic3, cordova, spring, s3, javascript, java
How to upload files from an Ionic 3 / Cordova app directly to a Minio server or Amazon S3 with pre-signed URLs.
Published: February 15, 2017 • Updated: February 16, 2018 • java, s3
In this article we have a closer look at Minio, a self hosted S3 compatible server, and how to connect a Java application to it.
Published: February 12, 2017 • Updated: November 16, 2017 • ionic3, cordova, spring, javascript, java
In this article we create an Ionic 3 application where the user can select a picture from the cordova camera plugin and the app uploads it to a Spring Boot server application.
Published: February 05, 2017 • ionic3, spring, java, javascript
How to implement a JWT authentication between an Ionic 3 app and a Spring Boot back end.
Published: January 26, 2017 • Updated: November 16, 2017 • angular, ionic3, spring, java, javascript
Example of form validation in an Ionic 3 application. How to create custom synchronous and asynchronous validators and how to validate data on the server with the Java Bean Validation framework.
Published: January 24, 2017 • Updated: February 16, 2018 • spring, java
How to create RSS and Atom feeds with the Spring Framework and the ROME library
Published: January 22, 2017 • Updated: December 05, 2017 • angular, javascript
Published: January 20, 2017 • Updated: June 19, 2017 • database, javascript
Published: January 18, 2017 • Updated: May 18, 2017 • ionic3, cordova
Published: January 16, 2017 • Updated: November 16, 2017 • ionic3, cordova
Published: January 14, 2017 • Updated: December 23, 2017 • ionic3, spring, java, javascript
Published: January 13, 2017 • Updated: January 17, 2018 • ionic3, cordova
Published: January 08, 2017 • Updated: December 23, 2017 • java, spring
Published: January 04, 2017 • extjs
Published: January 04, 2017 • Updated: October 25, 2017 • javascript