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Simple Firebase service for Angular 2

If you want a very simple alternative to Angularfire you may create a firebase service very easily. I made this to avoid extra configuration when it comes to adding npm packages and configuring for bundling. This is done by downloading the scripts from Firebase CDN directly by using a dynamically created script tag. Once the service is initialized you'll find the database in the public database property, and you just use the regular Firebase API. (Example: this.fbservice.database.ref('someproperty').set(somevalue) - and remember to have fbservice : FireBaseService in your component constructor to inject the service. ) And here's the code for the service: import { Injectable } from '@angular/core' ; import { Observable } from 'rxjs/Observable' ; declare const firebase : any ; const config = { apiKey : " " , authDomain : " .firebaseapp.com" , databaseURL : " " , storageBucket : ...
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My VNC based development environment with Visual Studio Code running on Ubuntu

I've used this setup for my development environment for several years - giving me a developer desktop I can access anywhere. Even from my mobile phone. I've been fixing bugs, writing code and deployed emergency fixes from the bus, train and mountain tops. The setup is based on a lightweight desktop environment. There are lot of alternatives, but I've chosen fluxbox. From a plain AWS Amazon Ubuntu 16.04 ec2 instance I've started like this: sudo apt-get update sudo apt-get install fluxbox Download and extract tigervnc from https://github.com/TigerVNC/tigervnc/releases (I downloaded the binary file from https://bintray.com/tigervnc/stable/tigervnc/1.7.0 named tigervnc-1.7.0.x86_64.tar.gz ) then extract: tar -xvzf tigervnc-1.7.0.x86_64.tar.gz You need to install: sudo apt-get install x11-xkb-utils You need to edit .vnc/xstartup: nano .vnc/xstartup last line replace "twm &" with: fluxbox & Then you can start the...
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Secure file transfer with Java and Versile

Just made an example of how to transfer a file over a secure and authenticated connection in pure Java - without having to use additional technology like ssh/scp. Versile has all you need for creating a secure and authenticated connection, and you'll decide what files you want to expose - nothing more - nothing less. This is the file server (include versile.jar in your classpath - and create a file called "personregister.txt" in the working directory): package versileexample; import java.io.File; import java.io.FileNotFoundException; import java.io.RandomAccessFile; import java.security.interfaces.RSAPublicKey; import java.util.logging.Level; import java.util.logging.Logger; import org.versile.Versile; import org.versile.common.auth.VAuth; import org.versile.common.auth.VCredentials; import org.versile.common.auth.VPrivateCredentials; import org.versile.common.peer.VInetSocketPeer; import org.versile.common.peer.VPeer; import o...
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Converting from linear to logarithmic scale

A simple function useful to plot a logarithmic scale. Just provide it with the min and max values of the scale and the value you want to convert - and you'll get in return a value as it should be positioned on a logarithmic scale in the given range. public double toLogScale(double min, double max,double val) { double logmin = Math.log(min); double logmax = Math.log(max); double logscale = (Math.log(val)-logmin) / (logmax-logmin); return min+(max-min)*logscale; }
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Ubuntu desktop in the cloud accessible with VNC

To create a Ubuntu desktop on Amazon EC2 that can be accessed by VNC I did the following steps: 1. Create 64-bit Ubuntu server instance 2. Install ubuntu desktop: sudo apt-get install ubuntu-desktop 3. Install x11vnc sudo apt-get install x11vnc 4. Install xvfb sudo apt-get install xvfb 5. Configure x11vnc sudo nano /etc/init/x11vnc.conf start on login-session-start script /usr/bin/x11vnc -xkb -auth /var/run/lightdm/root/:0 -noxrecord -noxfixes -noxdamage -rfbauth /etc/x11vnc.pass -forever -bg -rfbport 5900 -o /var/log/x11vnc.log end script And you should also set a password for your vnc sessions: sudo x11vnc -storepasswd /etc/x11vnc.pass 6. Configure X server to use xvfb: (Add the xserver-command line) sudo nano /etc/lightdm/lightdm.conf [SeatDefaults] greeter-session=unity-greeter user-session=ubuntu xserver-command=/etc/X11/xinit/xserverrc (Replace the exec line) sudo nano /etc/X11/xinit/xserverrc #!/bin/sh #exec /us...
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Exporting Kendo UI GRID to Excel with Java

This is a simple method of creating an Excel export function on your Kendo UI grid with a Java EE server. JS function to trigger Excel export In your web-page with the grid - insert this JS function. You should create a button or similar that calls this when you want to perform the export from the UI. function exportGridToExcel() { var grid = $("#grid").data("kendoGrid"); var currentPage = grid.dataSource.page(); var allPages = new Array(); for(var n=1;n<=grid.dataSource.totalPages();n++) { grid.dataSource.page(n); var view = grid.dataSource.view(); for(var x=0;x<view.length;x++) { allPages.push(view[x]); } } $("#excelExportGridData").val(JSON.stringify({"rows": allPages, "cols": grid.columns})); $("#exportToExcelForm").submit(); grid.dataSource.page(currentPage); } Hidden form and iframe You also nee...
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