cupuyc

Testing on Mac

Add to /etc/pf.conf

block out proto udp from any to any
block in proto udp from any to any
pass out proto udp from any to any port 53
pass in proto udp from any to any port 53

To apply:

dbist

CockroachDB and Docker Compose

This is the first in a series of tutorials on CockroachDB and Docker Compose

• Information on CockroachDB can be found here.
• Information on Docker Compose can be found here

1. Install Docker Desktop

Because we already have an official CockroachDB docker image, we will use that in our docker-compose.yml file. We recommend you use one of the current tags instead of latest.

anton-fomin

// Should be put into ~/.sbt/1.0/plugins/bloop.sbt
// By default, this file does not do anything.
// If the environment variable BLOOP_ENABLED has the value 'true',
// then this file enables sbt-bloop.

if (System.getenv("BLOOP_ENABLED") == "true") {
  addSbtPlugin("ch.epfl.scala" % "sbt-bloop" % "1.3.4")
} else Nil

rowland007

Keep a Downstream git Repository Current with Upstream Repository Changes

A downstream repository (aka a “fork”) maintainer commonly needs to stay current with upstream work (aka "original"). The case is development continues on the upstream repo while you work on your own origin fork. You want to fetch the upstream changes and apply them to your origin so you don't make conflicts.

The following steps allow you to achieve this on the command line in a local git repository.

Add the Remote Upstream Repository

jdegoes

//
  // EXERCISE 4
  //
  // Create a type class to describe `printLine` and `readLine`.
  //
  trait Console[F[_]] {
    def printLine(line: String): F[Unit]

    def readLine: F[String]
  }

aaronlevin

import scala.annotation.tailrec

/**
 * A Type-aligned list is a list of functions which can be
 * chained together. They are "type-aligned" because their
 * types all line. For example, suppose you have the following
 * functions:
 *
 *   val foo: Int => String = i => i.toString
 *   val bar: String => Char = s => s.head

mrbar42

running:

bash create-vod-hls.sh beach.mkv

will produce:

    beach/
      |- playlist.m3u8
 |- 360p.m3u8

d1egoaz

If you want to learn Scala, I’d suggest:

• Install IntelliJ + Scala Plugin
• Don’t do the Coursera courses yet.
• Don’t do the “red book” Functional Programming in Scala yet.
• Do: http://underscore.io/books/
  • Essential Scala
  • Essential Play
  • Essential Slick
• Do Scala for the Impatient: https://www.amazon.com/Scala-Impatient-Cay-S-Horstmann/dp/0321774094
• The Neophyte’s Guide to Scala http://danielwestheide.com/scala/neophytes.html

cupuyc

Misspelled lookups

Given two strings, S1 and S2, we can define an edit distance as the minimum number of operations required to change S1 to S2.

The operations might be one of the following:

• delete a character
• insert a character
• substitute a character for another character

ptarjan

Scaling your API with rate limiters

The following are examples of the four types rate limiters discussed in the accompanying blog post. In the examples below I've used pseudocode-like Ruby, so if you're unfamiliar with Ruby you should be able to easily translate this approach to other languages. Complete examples in Ruby are also provided later in this gist.

In most cases you'll want all these examples to be classes, but I've used simple functions here to keep the code samples brief.

Request rate limiter

This uses a basic token bucket algorithm and relies on the fact that Redis scripts execute atomically. No other operations can run between fetching the count and writing the new count.