Programming Archives

What is the best event source for doing pub-sub with AWS Lambda?

AWS, Design Patterns, DynamoDB, Kinesis, Lambda, Programming, Serverless, SNS

AWS offers a wealth of options for implementing messaging patterns such as pub-sub with Lambda, let’s compare and contrast some of these options. The pub-sub pattern Publish-Subscribe (often shortened to pub-sub) is a messaging pattern where publishers and subscribers are decoupled through an intermediary broker (ZeroMQ, RabbitMQ, SNS, etc.). SNS + Lambda In the AWS ecosystem, the obvious …

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You need to use structured logging with AWS Lambda

AWS, Lambda, Programming, Serverless

This is a lesson that I wished I learnt when I first started using AWS Lambda in anger, it would have made my life simpler right from the start. But, we did get there before long, and it allowed us to track and include correlation IDs in our log messages (which are then pushed to an ELK stack)which would …

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I’m afraid you’re thinking about AWS Lambda cold starts all wrong

API Gateway, AWS, Lambda, Programming, Serverless

When I discuss AWS Lambda cold starts with folks in the context of API Gateway, I often get responses along the line of: Meh, it’s only the first request right? So what if one request is slow, the next million requests would be fast. Unfortunately that is an oversimplification of what happens. Cold start happens once for …

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Finding coldstarts : how long does AWS Lambda keep your idle functions around?

AWS, Lambda, Programming, Serverless

In the last post I compared the coldstart time for Lambda functions with different language, memory and code size. One of the things I learnt was that idle functions are no longer terminated after 5 minutes of inactivity. /2017/06/aws-lambda-compare-coldstart-time-with-different-languages-memory-and-code-sizes/ It is a fantastic news and something that Amazon has quietly changed behind the scene. However, …

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From F# to Scala – implicits

Programming, Scala

Read the whole series: Part 1 — type inference Part 2 — traits Part 3 — case class/object (ADTs) Part 4 — apply & unapply functions Part 5 — implicits <- you’re here Having looked at case class and extractors recently, the next logical thing would be partial functions. Since Andrea pointed me to a really well article on the subject I don’t think …

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From F# to Scala – apply & unapply functions

Programming, Scala

Read the whole series: Part 1 — type inference Part 2 — traits Part 3 — case class/object (ADTs) Part 4 — apply & unapply functions <- you’re here Part 5 — implicits Last time around we looked at Scala’s Case Class in depth and how it compares to F#’s Discriminated Unions. F# also has Active Patterns, which is a very powerful language …

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From F# to Scala – case class/object (ADTs)

Programming, Scala

Read the whole series: Part 1 – type inference Part 2 – traits Part 3 – case class/object (ADTs) <- you’re here Part 4 – apply & unapply functions Part 5 – implicits Continuing on from where we left off with traits last time around, let’s look at Scala’s case class/object which can be used to create Algebraic Data …

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From F# to Scala – traits

Programming, Scala

Read the whole series: Part 1 — type inference Part 2 — traits <- you’re here Part 3 — case class/object (ADTs) Part 4 — apply & unapply functions Part 5 — implicits Continuing on from where we left off with type inference last time around, let’s look at a language feature in Scala that doesn’t exist in F# – traits. Scala has …

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From F# to Scala – type inference

Programming, Scala

Read the whole series: Part 1 – type inference <- you’re here Part 2 – traits Part 3 – case class/object (ADTs) Part 4 – apply & unapply functions Part 5 – implicits It’s a new year, a new job, a new language (Scala) and runtime (JVM) to work with. After a week of learning …

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Advent of Code F# – Day 25

F#, Programming

ps. look out for all my other solutions for Advent of Code challenges here. Day 25 See details of the challenge here. Today’s input looks like this: cpy a d cpy 7 c cpy 362 b inc d dec b jnz b -2 … At last, we’re at the end of this year’s Advent of …

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