Tutorial by Examples: d

Conversion between JSON and Java objects (basic)

By default, Jackson (the library Play JSON uses) will try to map every public field to a json field with the same name. If the object has getters/setters, it will infer the name from them. So, if you have a Book class with a private field to store the ISBN and have get/set methods named getISBN/setI...

playframework • Java - Working with JSON

Using different Properties/Configuration for different environments like dev, qa, staging etc.

Large scale applications often need different properties when running on different environments. we can achieve this by passing arguments to NodeJs application and using same argument in node process to load specific environment property file. Suppose we have two property files for different enviro...

Node.js • Deploying Node.js applications in production

Compress files and folders using the tar command

Use the tar (tape archive) command to compress your files and folders. It is similar to creating .ZIP files in Windows environment. Syntax: tar -zcvf <output tar file> <source file> Example: tar -zcvf outputfile.tar.gz source file Here’s what those switches actually mean: -c: Cr...

Ubuntu • Basic Terminal commands

Create an inbound filter for the search

Inbound filter is applied when item is added to the search index and allows to specify whether item is included to the index or not. Examples when inbound filter can be used - do not include standard values and previous versions of the item in the index. Inbound filters are set in configuration: ...

sitecore • Search

Create an outbound filter for the search

Outbound filter can be used to filter the search results. One of the examples of outbound filter usage is removing items which user doesn't have access to from search results. Outbound filters are set in the configuration: <indexing.filterIndex.outbound> <processor type="Sitecore....

sitecore • Search

Delete all previous versions of the item in the index when adding new version

By default Sitecore adds all versions of the item to the sitecore_master_index. The drawback of that is that if users are using workflows and adding lots of versions all of them will be added to the search results in the content editor. Configuration: <event name="item:versionAdded" &...

sitecore • Search

Basic HTML Modal

A modal is a dialog window which can be displayed over the current page.  <button type="button" class="btn btn-success btn-lg" data-toggle="modal" data-target="#theModal">Open The Modal</b...

twitter-bootstrap • Modals

Open HTML file from app local folder or temp folder

To open a file from local folder or temp folder, target file must not be located in those folders' root. For security reasons, to prevent other content from being exposed by WebView, the file meant for displaying must be located in a subfolder: var uri = new Uri("ms-appdata:///local/html/html-...

uwp • WebView navigation

Indent an entire file using built-in indentention engine

In command mode(Esc) enter :gg=G to use Vim's built-in indention engine. Command PartDescriptionggstart of file=indent (when equalprg is empty)Gend of file You can set equalprg in your .vimrc to use a more sophisticated auto-formatting tool. For example, to use clang-format for C/C++ put the foll...

vim • Indentation

Processing long running queries with Node

Since Node is single-threaded, there is a need of workaround if it comes to a long-running calculations. Note: this is "ready to run" example. Just, don't forget to get jQuery and install the required modules. Main logic of this example: Client sends request to the server. Server sta...

Node.js • Performance challenges

Evaluated Expression

ASP.NET • Expressions

Code Block Within ASP Markup

ASP.NET • Expressions

Word Count Example in Hive

Docs file (Input File) Mary had a little lamb its fleece was white as snow and everywhere that Mary went the lamb was sure to go. Hive Query CREATE TABLE FILES (line STRING); LOAD DATA INPATH 'docs' OVERWRITE INTO TABLE FILES; CREATE TABLE word_counts AS SELECT word, count(1) AS count F...

hive • Getting started with hive

Hello world!

The example is taken from threejs website. You may want to download three.js and change the script source below. There are many more advanced examples under this link. HTML: <html> <head> <meta charset=utf-8> <title>My first Three.js app</title> <...

three.js • Getting started with three.js

Reading files: foreach vs. while

When reading a potentially large file, a while loop has a significant memory advantage over foreach. The following will read the file record by record (by default, "record" means "a line", as specified by $/), assigning each one to $_ as it is read: while(<$fh>) { pri...

Perl Language • Memory usage optimization

Verifying a Returned Value

[Test] public void Calculator_Add_ReturnsSumOfTwoNumbers() { Calculator calculatorUnderTest = new Calculator(); double result = calculatorUnderTest.Add(2, 3); Assert.AreEqual(5, result); }

unit-testing • Assertion Types

State Based Testing

Given this simple class, we can test that the ShaveHead method is working correctly by asserting state of the HairLength variable is set to zero after the ShaveHead method is called. public class Person { public string Name; public int HairLength; public Person(string name, in...

unit-testing • Assertion Types

Block access to LAN and out

docker network create -o "com.docker.network.bridge.enable_ip_masquerade"="false" lan-restricted Blocks Local LAN Internet Does not block Host running docker daemon (example access to 10.0.1.10:22)

Docker • Restricting container network access

Block access from containers to the local host running docker daemon

iptables -I INPUT -i docker0 -m addrtype --dst-type LOCAL -j DROP Blocks Access to host running docker daemon Does not block Container to container traffic Local LAN Internet Custom docker networks that doesn't use docker0

Docker • Restricting container network access

Block access from containers to the local host running docker daemon (custom network)

docker network create --subnet=192.168.0.0/24 --gateway=192.168.0.1 --ip-range=192.168.0.0/25 local-host-restricted iptables -I INPUT -s 192.168.0.0/24 -m addrtype --dst-type LOCAL -j DROP Creates a network called local-host-restricted which which: Blocks Access to host running docker daem...

Docker • Restricting container network access