AIMMOTH: 2016

2016-10-23

Rains Poncho (gul) 890kr

Jackor & Ytterplagg, stl. 50 (M), herr
Supersnygg poncho i gult av Rains. Säljes i befintligt skick för 890kr.

https://www.blocket.se/stockholm/Rains_Poncho__gul__69843575.htm?ma=1

Stripe byrå (Sara Larsson) 9 990kr

Supersnygga designbyrån Stripe finns i nyskick! Säljes i befintligt skick för 9 990kr. Nypris cirka 13 000kr.

Från den exklusiva möbelkedjan Svensson i Lammhult: Stripe är en vacker, uppseendeväckande byrå som bär tydliga kännetecken av formgivare Sara Larssons kärlek till det färgstarka. Som vanligt när det gäller A2 Designers är det hantverksmässig tillverkning och hög kvalitet som är ledorden.

Kartell Optic (kub, förvaring) 1000kr

Som nya! Tre i färgerna lila och röd. Dörrar ingår (360kr) men med trasiga fästen.

Säljes i befintligt skick. 500kr/st

Från Kartell: Denna mångsidiga kub är ett spännande inredningsobjekt. Optic är en förvaring i form av en kvadratisk box med antingen en öppen sida eller med dörr. Tack vare att man kan stapla dem på varandra uppstår möjligheten att skapa en vacker hylla, pelare eller ett enstaka litet bord. Ytan är utformad med kvadratiska låga pyramider, vilket skapar en mycket vacker visuell effekt och en "relief" i ytan. Går även att ha utomhus.

Mått: 41 x 41 x 41 cm

https://www.blocket.se/stockholm/Kartell_Optic__kub__forvaring__69842998.htm?ma=1

2016-10-13

Scala Request Uri Combinator Parser

URI Combinator Parser

In my last blog I created a URL parser but the HttpServletRequest is providing only path and query with the method getRequestUri() so I made a request URI parser too.

Code

This code needs the URL parser, see below.

	import scala.util.parsing.combinator.RegexParsers

	case class RequestUriTokens(path : Option[String], query : Option[String])

	/**
	* Useful parser when using HttpServletRequest.getRequestUri()
	*
	* @see javax.servlet.http.HttpServletRequest.getRequestUri()
	*/
	class RequestUriParser extends RegexParsers {

	private val requestUriParser = someRequest

	val notQuestionmark = """[^\?]*""".r
	val any = """.*""".r

	def someRequest = "/" ~> opt(notQuestionmark) ~ opt("?" ~> any) ^^ {
	case path ~ query => new RequestUriTokens(path, query)
	}

	def applyOnUri(uri : String) = parseAll(requestUriParser, uri) match {
	case Success(result, _) => Right(result)
	case Failure(failure, _) => Left(failure)
	case Error(error, _) => Left(error)
	}
	}

	object RequestUriParser {
	lazy val requestUriParser = new RequestUriParser

	def apply(uri : String) = requestUriParser.applyOnUri(uri)
	}

view raw HttpServletRequest Request Uri Parser.scala hosted with ❤ by GitHub

See

Link to the URL parser:
https://gist.github.com/AIMMOTH/b9903387cdf6b9377e9a7f6ca8887281

2016-10-12

Scala URL Parser Combinator

URL Parser Combinator

(updated 2016-10-16)

It has bugged me that there is no parser of an URL so I made one.

Parser Combinator

Scala provides an excellent tool of parsing using a mix of code in DSL (domain specific language) and regular expressions. Together with unapply it's easy to match and take out the matching pieces.

URL

From Wikipedia there are the following parts of an URL (some are optional):

scheme:[//[user:password@]host[:port]][/]path[?query][#fragment]

Code

Enjoy, I won't go into detail other than it breaks down the URL in the following order:

Split URL by

Mandatory scheme
Optional domain
Mandatory path
Optional query and fragment

Domain is split by

Authorization
Domain
Port

Usually a greedy regexp matcher is used until a delimiter.

	// https://github.com/scala/scala-parser-combinators
	import scala.util.parsing.combinator.RegexParsers

	case class UrlTokens(
	scheme : String,
	authorization : Option[(String, Option[String])],
	domain : Option[String],
	port : Option[Int],
	path : String,
	query : Option[String],
	fragment : Option[String]) extends RegexParsers {

	lazy val splitPath = HelperParser.splitPathBySlash(path)
	lazy val splitQueryToValuePairs = query map (HelperParser.splitIntoValuePairs)
	lazy val splitFragmentToValuePairs = fragment map (HelperParser.splitIntoValuePairs)
	}

	/**
	* <p>
	* From Wikipedia:
	* <pre>
	* scheme:[//[user:password@]host[:port]][/]path[?query][#fragment]
	* </pre>
	* </p>
	*
	* <p>
	* Parsing an URL:
	* </p>
	* <ol>
	* <li>Split by mandatory scheme, optional domain, mandatory path and then optional query and fragment</li>
	* <li>If there's a domain split by optional authorization, mandatory domain and optional port</li>
	* <ol>
	* <p>
	* Usually a parser is used by greedy regexp matching until a delimiter.
	* </p>
	*
	* @see http://www.scala-lang.org/files/archive/api/2.11.2/scala-parser-combinators/#scala.util.parsing.combinator.RegexParsers
	*/
	class UrlParser extends RegexParsers {

	def urlParser = scheme ~ opt(domain) ~ path ~ opt(query) ~ opt(fragment) ^^ {
	case scheme ~ domain ~ path ~ query ~ fragment => domain match {
	case Some((authorization, domain, port)) =>
	Right(new UrlTokens(scheme, authorization, Some(domain), port, path, query, fragment))
	case None =>
	Right(new UrlTokens(scheme, None, None, None, path, query, fragment))
	}
	}

	val notSlash = """[^\/]+""".r
	val notDot = """[^\.]+""".r
	val notColon = """[^:]+""".r
	val notAt = """[^@]+""".r
	val notColonOrSlash = """[^:\/]+""".r
	val numbers = """\d+""".r
	val notQuestionmarkOrHash = """[^\?#]+""".r
	val notHash = """[^\#]*""".r
	val any = """.*""".r

	def scheme = notColon <~ ":"

	def domain = "//" ~> opt(authorization <~ "@") ~ notColonOrSlash ~ opt(":" ~> port) <~ "/" ^^ {
	case optionalAuthorization ~ domains ~ optionalPort => (optionalAuthorization, domains, optionalPort)
	}
	def authorization = notColon ~ opt(":" ~> notAt) ^^ { case user ~ optionalPassword => (user, optionalPassword) }
	def port = numbers ^^ { case number => number.toInt }

	def path = notQuestionmarkOrHash
	def query = "?" ~> notHash
	def fragment = "#" ~> any

	def apply(url : String) = toResult(url, urlParser)
	def applyWith(url : String, parser : Parser[_]) = toResult(url, parser)

	def toResult(text : String, parser : Parser[_]) = {
	parseAll(parser, text) match {
	case Success(result, _) => Right(result)
	case Failure(error, _) => Left(error)
	case Error(error, _) => Left(error)
	}
	}
	}

	object UrlParser {
	lazy val urlParser = new UrlParser

	def apply(url : String) = urlParser(url)
	}

	/**
	* Parse common patterns.
	* <ul>
	* <li>Split domain with dot</li>
	* <li>Split path with slash</li>
	* <li>Split query or fragment with ampersand and then create value pairs by split by equals</li>
	* </ul>
	*/
	object HelperParser extends RegexParsers {

	implicit def parserToOption[T](parserResult : ParseResult[T]) = parserResult match {
	case Success(result, _) => Some(result)
	case _ => None
	}

	val notDot = """[^\.]+""".r
	def domainsByDot = repsep(notDot, ".")
	def splitDomainByDot(domain : String) : Option[List[String]] = parseAll(domainsByDot, domain)

	val notSlash = """[^\/]*""".r
	def pathBySlash = repsep(notSlash, "/")
	def splitPathBySlash(path : String) : Option[List[String]] = parseAll(pathBySlash, path)

	val notEquals = """[^\=]+""".r
	def valuePairs = repsep(pair, "&")
	def pair = notEquals ~ "=" ~ opt(notEquals) ^^ {
	case key ~ equal ~ optionalValue => (key, optionalValue)
	}
	/**
	* Split by ambersand (&) and then equals (=)
	*/
	def splitIntoValuePairs(text : String) : Option[List[(String, Option[String])]] = parseAll(valuePairs, text)
	}

view raw UrlParser.scala hosted with ❤ by GitHub

2016-10-11

Javascript monad Maybe with Monet

The Monad Maybe

Maybe aka option or optional is very useful for preventing null. Using the Javascript library Monet it's quite easy to use this monad.

Preventing null

You have a variable but don't know if it's null. With Maybe, you wrap it and test if it is "some".

	var couldBeNull = Maybe.fromNull(suspiciousVariable);
	if (couldBeNull.isSome()) {
	// Ok
	} else {
	// KO!
	}

view raw Monet Maybe.js hosted with ❤ by GitHub

Transform or map

Monads are also useful to transform a value to another. Think of this example:

	var text = "10";
	var integer = parseInt(text);
	var array = new Array(integer);
	for (var i=0; i<integer; i++) {
	array[i] = i;
	}
	console.log(array); // [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]

view raw Old.js hosted with ❤ by GitHub

Each step is instancing a variable and making a "halt". With a monad, you can "go with the flow" and do it all in one step:

	console.log(
	Some("10").map(function(text) {
	return parseInt(text);
	}).map(function(integer) {
	return new Array(integer);
	}).map(function(array) {
	for (var i=0; i<array.length; i++) {
	array[i] = i;
	}
	return array;
	}).some();
	); // [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]

view raw Monet Maybe Mapping.js hosted with ❤ by GitHub

Sample

https://jsfiddle.net/yapdd5xv/15/

2016-10-07

Monad implementation in Scala with example

Monad in Scala

Monad

Difficult to explain but useful for nice code.

Implementation in Scala

This is a simple implementation of a monad in Scala which makes Any able to use monad's definition called flatmap (>>=).

/**

* Monad implementation

final case class Monad[T](val value : T) {

def >>=[S](f : T => S) : Monad[S] = {

new Monad(f(value))

}

override def toString = String.valueOf(value)

}

/**

* Implicit wrap Any to a Monad.

implicit def anyToMonad[T](value : T): Monad[T] = new Monad[T](value)

Example

Using this implementation, Any can use flatmap wihch could be used as follows.

// Example

"10" >>= Integer.parseInt >>= (_ + 10) >>= (0 to _) >>= println

Prints

Range(0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20)

Fiddle

Try it out at Scala Fiddle!

https://scalafiddle.io/sf/nMVS7E1/2

2016-09-01

Scala Stack with Google Flexible Environment

(this article is not yet completed)
(updated 2016-11-11)

I've created a few Maven projects based on Google Flexible Environment and Scala backend which produces HTML, CSS and JavaScript without any files (.html, .css, .sass, .less, .js) and without any frontend builder like Gulp or Grunt.

Goal

To produce all frontend from Scala backend utilizing shared code and to be fully tested.

Infographic

Scala servlets creates HTML with CSS and JavaScript.

This is a graphic representation of how it works.

All code is written in Scala
Code may share

Resources
Validation
Routes
Logic
Translations and other data
Structure of

HTML
CSS

A servlet can read Scala JS source code and compile a JavaScript

This includes the shared code

A servlet can build HTML with CSS
Other servlets can provide REST API and also use the shared code
All code can be unit tested and all code can be tested in the same test

This means that the Scala stack covers both frontend and backend.

Code

There is a repository called Scala Stack at Github. There is one branch for jQuery ~~in development~~ and one branch for Angular ~~which is only started~~:

*Unfortunately I can't afford Google Compute Engine running 24/7 and was forced to shut them down. If Google Compute Engine would scale from 0 to minimize expense I could start them again.

Examples

I'm currently working on a example using jQuery ~~(in progress)~~ and one using Angular ~~(started)~~.

Note that Scala JS source is placed in webapp, an alternative could be resources

2016-07-20

Migration from Google App Engine to Flexible Environment

Migration

Google App Engine is great since it's reliable and have tons of services free to use. Compared to a platform like Heruko, you get search, database, image and other services for free. But as a javaite, it's unfortunate that it only supports Java 7. The only way to move forward is to migrate to Flexible Environment. But be aware, not all services can migrate!

Start: App Engine

Let's start with a simple App Engine Maven project and then migrate it.

Prerequisites

Use the following guide to install Java 7 SDK and Maven.

https://cloud.google.com/appengine/docs/java/tools/maven

Create Artifact

Use Maven to create the simple appengine skeleton artifact.

Run
$ mvn archetype:generate -Dappengine-version=1.9.38 -Dapplication-id=whatever -Dfilter=com.google.appengine.archetypes:
Select "1"
1: remote -> com.google.appengine.archetypes:appengine-skeleton-archetype (A skeleton application with Google App Engine)
Select "6"
6: 2.1.0-1.9.38
Enter group id (same as your Java package name for the project)
Define value for property 'groupId':
Enter your name for your project
Define value for property 'artifactId': :
Enter first version
Define value for property 'version': 1.0-SNAPSHOT:
Enter Java package (same as group id)
Define value for property 'package':
Enter gcloud version (find latest here)
Define value for property 'gcloud-version': 2.0.9.111.v20160527
Confirm your selection
Y:

Maven have now created an App Engine project in a subfolder. Start it with $ mvn appengine:devserver

Notice the layout and the few files needed.

Simple layout with few files

Migration: Flexible Environment

Let's go for Flexible Environment and Java 8!

Prerequisites

Install Java 8 SDK and never look back!
Note: that App Engine uses Jetty which need Java 7 to work with JSP. If you install Java 8 it will be difficult for you to run your old App Engine projects.
Install Google Cloud SDK. Make sure Python is on path after installation!
https://cloud.google.com/sdk/
Install the app-engine component to GCloud
$ gcloud components install app-engine-java
https://cloud.google.com/appengine/docs/flexible/java/maven

Migration

Follow the steps in the following guide.

https://cloud.google.com/appengine/docs/flexible/java/migrating-an-existing-app

Add the following line in appengine-web.xml
```
<vm>true</vm>
```
Add the following two plugins in pom.xml.

The first one to be able to run with GCloud maven goals
And the second to set Java 8 compilation.

<plugin>
   <groupId>com.google.appengine</groupId>
   <artifactId>gcloud-maven-plugin</artifactId>
   <version>2.0.9.106.v20160420</version>
</plugin>

      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <version>3.3</version>
        <artifactId>maven-compiler-plugin</artifactId>
        <configuration>
          <source>1.8</source>
          <target>1.8</target>
        </configuration>
      </plugin>

Run with
$ mvn gcloud:run

2016-07-12

Google Flexible Environment with Virtual Scala JS Compiler

After several months I managed to translate Scala JS Fiddle to Google Java Flexible Environment

Goal

To create a project with Scala backend which generates JavaScript in a virtual compiler.

Live Demo

The live demo uses a Scala Servlet to generate HTML (Scala Tags) with a JavaScript. A second Scala Servlet is responding to "/javascript.js" and is using a virtual compiler to compile a String with simple Scala JS code to a JavaScript

https://scala-js-compiler.appspot.com/index.scala

Environment

It's a Maven project using Google Flexible "Compat" Environment which includes some App Engine features (not used) and Java 8 with Servlet API 3.1.

Source

Check out my Github

https://github.com/AIMMOTH/scala-js-compiler/tree/web-demo

2016-07-02

My AirBnB

Mariabergets topp

Stockholm, Stockholms län, Sverige

Mitt ställe ligger nära Monteliusvägen, Ivar Los park, The Bishops Arms, Akkurat restaurang & bar, Rival, Mariatorget, Mariaberget, Tavastgatan, Brännkyrkogatan, Slussen, Bysistorget, Münchenbrygge...

2016-06-29

H1Z1 King of the Kill: Art of Camping

Art of Camping

Check my new tactic for the current (new) map

Art of Camping: Z2 Map

This is the tactic I usually use. It started with me trying to get to top 10 in the most safe way and now I regularly accomplish that. But to win you always need to win duels.
It has three phases:

Parachute Dive down to a safe area and loot
Movement Approach the circles close to the edge to avoid players
Final Win duels to win the game!

Parachute

Go as far out to the edge as possible. You can fly further by strafing, using A and D. It's possible to cover two squares.

There are plenty of safe places but if you start in the middle it can be difficult reaching them

These areas usually empty from players and have plenty of loot. Notice that from F-G 5-6 it's quite difficult to parachute into a safe area!

Movement

Timing

Each circle appear in intervals and the gas move in between. The first circle appears after 5 minutes, then there's a delay of 5 minutes and then shrinks for 5 minutes. After coming circles shrinks during 1 minute.
The first circle have 5 squares in radius and the next four shrinks it's radius with 1 square. Then they are halved.
They are named after their square radius.

The first circle is called "the five" since it's radius is 5 squares.
The next three circles shrinks after 3min

The four
The three
The two

The next circles shrinks after 2min

The one covering one square and shrinks relatively fast!
The half
The quarter
The eighth
...

Speed

It's really useful to know how fast you travel to measure how long it will take you to reach the circle

Barefoot ~2:05/square
Shoes ~2:00/square
Sneakers ~1:50/square
Car

Full throtle ~30s/square
No throtle ~40s/square

Since the first circle shrinks after 5min and during 5min then you have 10min to run into it, and with shoes you can cover 5 squares during this time.

Healing and Gas Damage

If you're late and need to run through gas, make sure to have health packs. Each pack heals 1hp/s during 1min (60hp in total) and bandages heals 1hp/s during 10s (10 in total).

Gas make 1hp/s damage. This means you can use a health pack and run through the gas for 1min which covers a half square!

During the final the gas becomes stronger and reaches 2-3hp/s.

Approach

When heading towards a circle, try to avoid areas with lots of players and try to move around them and into an area which is in the outskirts.

Outside the roads are safe. Cities and fields are hazardous

Example

Run around the hazardous areas and only if necessary, try to run between those areas and move towards the edge of the map.

Move around the center and continue to the edge

Videos

You can watch some videos I've recorded here Art of Camping Playlist

Final

At the one and onward, there's usually around 10 players left and this is called the final. The gas damage is about 2-3 per second. You need to win duels at this point!

"The one" appear and it could be a good idea to take a chance and camp on the island!

2016-06-21

Logging with Flexible Environment and Jetty

Problem

Logging was not available for Google Flexible Environment with Java 8 and Jetty 9. But after reading Jetty documentation all needed was added SLF4J as dependency and use it's Logger.

Solution

Add SL4FJ as dependencies in pom:

</dependency>

<artifactId>slf4j-simple</artifactId>

</dependency>

Use org.slf4j.LoggerFactory and org.slf4j.Logger to log:

import org.slf4j.Logger;

import org.slf4j.LoggerFactory;

private static Logger logger = LoggerFactory.getLogger(JavaServlet.class);

logger.info("Info logging!");

Deployed

When deployed, the logging is shown in STDERR

2016-06-01

Flexible Environment with Scala

Started a new Maven project with Google's Flexible Environment including Java 8, Scala and Web Servlets 3.1.

Source code

You can find it here:
https://github.com/AIMMOTH/scala-js-compiler/tree/java8-scala-flexible-environment-web-servlet-3.1

2016-05-30

Uppdated! "Cannot determine the default location of the Google Cloud SDK" Solved

Error

Got a really annoying error while trying to run my local Flexible Environment with GCloud
$ mvn -Dgcloud.gcloud_directory="c:\path\to\gcloud-sdk\" gcloud:run
[ERROR] Cannot determine the default location of the Google Cloud SDK.
[ERROR] If you need to install the Google Cloud SDK, follow the instructions located at https://cloud.google.com/appengine/docs/java/managed-vms
[ERROR] You can then set it via <gcloud_directory> </gcloud_directory> in the pom.xml
[ERROR]
org.apache.maven.plugin.MojoExecutionException: Unkown Google Cloud SDK location:C:\...\gcloud_sdk
at com.google.appengine.gcloudapp.AbstractGcloudMojo.setupInitialCommands(AbstractGcloudMojo.java:170)
at com.google.appengine.gcloudapp.GCloudAppRun.getCommand(GCloudAppRun.java:306)
at com.google.appengine.gcloudapp.GCloudAppRun.execute(GCloudAppRun.java:292)
at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:134)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:207)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:153)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:145)
at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:116)
at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:80)
at org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder.build(SingleThreadedBuilder.java:51)
at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(LifecycleStarter.java:128)
at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:307)
at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:193)
at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:106)
at org.apache.maven.cli.MavenCli.execute(MavenCli.java:863)
at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:288)
at org.apache.maven.cli.MavenCli.main(MavenCli.java:199)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:289)
at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:229)
at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:415)
at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:356)
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 3.441 s
[INFO] Finished at: 2016-05-30T20:21:34+02:00
[INFO] Final Memory: 24M/380M
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal com.google.appengine:gcloud-maven-plugin:2.0.9.74.v20150814:run (default-cli) on project scala-js-compiler: Execution error: org.apache.maven.plugin.MojoExecutionException: Unkown Google Cloud SDK location:C:...\gcloud_sdk -> [Help 1]

Solution

It was much easier to solve! Just add Python to path (which is bundled in the Gcloud SDK).

~~But managed to use the locally installed python to run the python script which starts development server:~~
$ cd project
$ c:\...\gcloud_sdk\google-cloud-sdk\platform\bundledpython\python.exe c:\...\gcloud_sdk\google-cloud-sdk\bin\dev_appserver.py src\main\webapp

2016-05-28

Majorca Picture with the Golden Spiral

In April me and my mom visited Majorca. There was an interesting formation. I shoot it and found out that the picture had a criss-cross composition. I made a crop with the Golden Spiral and this is the result.

Reference

Golden Spiral at Wikipedia

2016-04-02

Webapp with HTML, CSS and JavaScript written in Scala

ISO Scala

This is an example of HTML, CSS and JavaScript written in Scala.

Technics

Different parts are written in different ways

Backend, Scala implementation of a Java Servlet
HTML and CSS, using ScalaTags to generate HTML in a String
JavaScript, built with ScalaJS

Two Builds

There are two different builds

Backend, using plain Maven to build and setup the project
JavaScript, built with SBT and using ScalaJS dependencies

Example

View a whole example at

https://github.com/AIMMOTH/iso-scala