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import scala.annotation.tailrec
import scala.collection.immutable.HashMap

case class TrieNode(h: HashMap[Char, TrieNode], isWord: Boolean = false)
object TrieNode {
  def empty = TrieNode(HashMap.empty)

  def buildTrieNode(s: List[Char], t: TrieNode = TrieNode.empty): TrieNode = {
    s match {
      case Nil => t.copy(isWord = true)

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case class TrieNode[T](edgeList: Map[T, TrieNode[T]] = Map.empty[T, TrieNode[T]], isLeaf: Boolean = false,
                       isEntry: Boolean = false)

object TrieNode {
  def emptyTrieNode[T]: TrieNode[T] = {
    TrieNode[T]()
  }

  def newTrieNode[T](data: T): TrieNode[T] = {
    TrieNode[T](edgeList = Map[T, TrieNode[T]]((data, emptyTrieNode[T])))

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package akkahttptest

import akka.http.Http
import akka.stream.ActorFlowMaterializer
import akka.actor.ActorSystem
import akka.stream.scaladsl.{Sink, Source}
import akka.http.model._

object TestClient extends App {

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How to create an HTTPS certificate for localhost domains

This focuses on generating the certificates for loading local virtual hosts hosted on your computer, for development only.

Do not use self-signed certificates in production ! For online certificates, use Let's Encrypt instead (tutorial).

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How to setup Let's Encrypt for Nginx on Ubuntu 18.04 (including IPv6, HTTP/2 and A+ SLL rating)

---

Virtual hosts

Let's say you want to host domains first.com and second.com.

Create folders for their files:

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import java.io.ByteArrayOutputStream
import java.time.Duration
import java.util.concurrent.Executors
import java.util.{Properties, Timer, TimerTask, UUID}

import Models.{Message, SystemMessage, UserMessage, msgAvroSchema}
import com.sksamuel.avro4s.{AvroInputStream, AvroOutputStream, AvroSchema}
import org.apache.kafka.clients.consumer._
import org.apache.kafka.clients.producer._
import org.apache.kafka.common.errors.WakeupException

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About

Example on how to run locally an AWS Lambda via API Gateway using localstack.

Based on...

1. https://stackoverflow.com/questions/44547574/create-api-gateway-in-localstack/48682628
2. https://ig.nore.me/2016/03/setting-up-lambda-and-a-gateway-through-the-cli/

Usage

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apiVersion: v1
kind: Service
metadata:
  name: redis-service
spec:
  type: LoadBalancer
  selector:
    app: redis
  ports:
    - name: redis

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Applied Functional Programming with Scala - Notes

Copyright © 2016-2018 Fantasyland Institute of Learning. All rights reserved.

1. Mastering Functions

A function is a mapping from one set, called a domain, to another set, called the codomain. A function associates every element in the domain with exactly one element in the codomain. In Scala, both domain and codomain are types.

val square : Int => Int = x => x * x

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import scala.slick.lifted.CanBeQueryCondition
// optionally filter on a column with a supplied predicate
case class MaybeFilter[X, Y](val query: scala.slick.lifted.Query[X, Y]) {
  def filter[T,R:CanBeQueryCondition](data: Option[T])(f: T => X => R) = {
    data.map(v => MaybeFilter(query.filter(f(v)))).getOrElse(this)
  }
}

// example use case
import java.sql.Date