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Showing posts from April, 2017

AWS Glue is a fully managed ETL service that makes it easy to move data between your data stores.

AWS Glue simplifies and automates the difficult and time consuming data discovery, conversion, mapping, and job scheduling tasks. AWS Glue guides you through the process of moving your data with an easy to use console that helps you understand your data sources, prepare the data for analytics, and load it reliably from data sources to destinations.

What is Big O Notation

It is the relative representation of the complexity of an algorithm.
It describes how an algorithm performs and scales.
It describes the upper bound of the growth rate of a function and could be thought of the worst case scenario.

Function without parameters is an antipattern.

There are certain scenarios in which it might be useful of function without parameters, but those are very rare and mostly related to already-broken design. 
If the function doesn't have any params, then what does it do? Where does it take the input and state? It could a global one — but that is an antipattern, too. 
Functions need input and output and should be pure.

Top universities have collaborated with Massive Open Online Course (MOOC) providers to launch their online master’s degree.

The first MOOC-based degree was announced back in 2013. It took two years for the next one to be announced in 2015. But in the last year or so, MOOC providers have announced seven more completely-online master's degrees. In fact, Coursera plans to offer 20 such degrees by the end of 2019.

Subscribe with Amazon.

Sellers of digital products and services can utilize Subscribe with Amazon to manage and operate a subscription based payment and consumption model through integration with Amazon APIs. After integration, sellers can find themselves listed on Amazon's subscription storefront.

How to run script from Internet URL

curl -L | bash The -L flag is for location. If the server reports that the requested page has moved to a different location, this option will make curl redo the request on the new place.

The pipe | links the two commands so that the output of the curl command becomes the input of the bash command.

If you want to run a script from GitHub and you need to get the URL of raw script.

To pass arguments to the script:
curl -sL | bash /dev/stdin arg1 arg2 Bourne shell also supports -s to read from stdin. curl -sL | bash -s arg1 arg2 -s, --silent Silent or quiet mode. Don't show progress meter or error messages. Makes Curl mute. It will still output the data you ask for, potentially even to the termi- nal/stdout unless you redirect it.

How to use Dell iDrac to reboot your server from command line

Connect to the Dell Remote Access Controller (Drac) IP address via SSH. Then execute:
racadm serveraction <action>

whereas you replace <action> with one of the following:

powerdown — Powers down the managed system.powerup — Powers up the managed system.powercycle — Issues a power-cycle operation on the managed system. This action is similar to pressing the power button on the system's front panel to power down and then power up the system.powerstatus — Displays the current power status of the server ("ON", or "OFF")hardreset — Performs a reset (reboot) operation on the managed system.
So, to power off and back on your server, you just type racadm serveraction powercycle.

If your Drac crashes for any reason, you may want to reset it: racadm racreset

If you want to have information about your current server, type: racadm getsysinfo

Google G Suite can be configured using Security Keys

They are actual physical key-like dongles that plug into a computer and use Bluetooth or near-field communications (NFC) to verify a user's authenticity.

Spend a few minutes, just once, to set it up, and you're good to go from there on out. If you use different devices frequently as part of your work setup, this security feature could save you lots of time over the long run.

Malware attacks on Apple's Mac computers

According to the McAfee Labs, malware attacks on Apple's Mac computers were up 744% in 2016, and its researchers have discovered nearly 460,000 Mac malware samples, which is still just a small part of overall Mac malware out in the wild.

Android and Linux: Indicator KDE Connect

See Android notifications on your desktop
Check current battery level
Send and receive files to/from phone/desktop
Use phone as a mouse touchpad & keyboard
Ring your device to find it
Control desktop media player using phone
Clipboard sync between phone and desktop
View device information (e.g., battery)
Run commands & launch apps
Send SMS

Google Cloud Dataflow dramatically simplifies and accelerates ingestion and processing compared to platforms like Spark, Hadoop, and Storm.

Google Cloud Dataflow's unified batch and streaming programming model and simple, high-level language reduce both latency and errors.

Your big data pipeline for GCP
Manage ETL tasks to filter, format, enrich, and ingest new data into BigQuery, or process data already stored on Cloud Storage, BigQuery, and Bigtable.

Fully managed and flexible
Dataflow automatically rebalances and autoscales worker resources to let you run large-scale parallel processing without operational headaches.

Unrivaled price to performance
Only pay for what you use. As resources scale up or down, you automatically get the best performance at the best price.

Google Advanced Sheets service

The Advanced Sheets service lets you access the Sheets API using Apps Script. Much like Apps Script's built-in Sheets service, this API allows scripts to read, edit, format and present data in Google Sheets. In most cases, the built-in service is easier to use, but this advanced service provides a few extra features.

Google Compute Engine zone

Which Google Compute Engine zone would you like to use as project default?
If you do not specify a zone via a command line flag while working with Compute Engine resources, the default is assumed. [1] asia-east1-a [2] asia-east1-c [3] asia-east1-b [4] asia-northeast1-a [5] asia-northeast1-b [6] asia-northeast1-c [7] asia-southeast1-a [8] asia-southeast1-b [9] europe-west1-c [10] europe-west1-b [11] europe-west1-d [12] us-central1-f [13] us-central1-a [14] us-central1-c [15] us-central1-b [16] us-east1-d [17] us-east1-b [18] us-east1-c [19] us-west1-a [20] us-west1-b

HTML5 Element provides a secure way to authenticate users.

The <keygen> element specifies a key-pair generator field in a form.

When the form is submitted, two keys are generated, one private and one public.

The private key is stored locally, and the public key is sent to the server.

The public key could be used to generate a client certificate to authenticate the user in the future.

How to upgrade ubuntu server system

Install the update-manager-core package if it is not already installed.
Make sure the Prompt line in /etc/update-manager/release-upgrades is set to normal.
Launch the upgrade tool with the command sudo do-release-upgrade.
Follow the on-screen instructions.

XHTML is HTML redesigned as XML.

There are many different browser technologies. Some browsers run on computers, and some browsers run on mobile phones or other small devices.

Smaller devices often lack the resources or power to interpret "bad" markup.

XML is a markup language where documents must be marked up correctly.

By combining the strengths of HTML and XML, XHTML was developed.

Close all HTML elements properly

Empty elements can be "closed" in the opening tag like this: <br />.

HTML5 does not require empty elements to be closed. But if you want stricter validation, or if you need to make your document readable by XML parsers, you must close all HTML elements properly.

There are websites which provide online contests

TopCoder (offers online contests for programmers).
CodeChef Programming Competition
HackerEarth - Programming challenges and Developer jobs

On these websites you basically create profile there are always some contests on going and you can participate and win big prize money / job offers / goodies and much more.

rsync - a fast, versatile, remote (and local) file-copying tool

       rsync - a fast, versatile, remote (and local) file-copying tool

       Local:  rsync [OPTION...] SRC... [DEST]

       Access via remote shell:
         Pull: rsync [OPTION...] [[email protected]]HOST:SRC... [DEST]
         Push: rsync [OPTION...] SRC... [[email protected]]HOST:DEST

       Access via rsync daemon:
         Pull: rsync [OPTION...] [[email protected]]HOST::SRC... [DEST]
               rsync [OPTION...] rsync://[[email protected]]HOST[:PORT]/SRC... [DEST]
         Push: rsync [OPTION...] SRC... [[email protected]]HOST::DEST
               rsync [OPTION...] SRC... rsync://[[email protected]]HOST[:PORT]/DEST

       Usages with just one SRC arg and no DEST arg will list the source files instead of copying.

       Rsync is a fast and extraordinarily versatile file copying tool.  It can copy locally, to/from another host over any remote shell, or to/from a remote rsync dae‐
       mon.  It offers a large number of options that control every aspect of its behavior and permit very flexible specification of the set o…