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Test Automation Concepts – Test Data and Aliases

April 5, 2016 | Software Consultancy

Test Automation Concepts – Test Data and Aliases

This post is part of a series which introduce key concepts in successful test automation. Each post contains sample code using the test-automation-quickstart project, a sample Java test automation framework available from Github.

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DZone Repost: Testing Serverless Functions

February 11, 2022 | AWS, Cloud, GCP, Kubernetes, Microservices, Open Source, Software Consultancy

DZone Repost: Testing Serverless Functions

Serverless functions are easy to install and upload, but we can’t ignore the basics. This article looks at different strategies related to testing serverless functions.

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Data Science on Steroids: Productionised Machine Learning as a Value Driver for Business

July 31, 2018 | Machine Learning

Data Science on Steroids: Productionised Machine Learning as a Value Driver for Business

Machine Learning, alongside a mature Data Science, will help to bring IT and business closer together. By leveraging data for actionable insights, IT will increasingly drive business value. Agile and DevOps practices enable the continuous delivery of business value through productionised machine learning models and software delivery.

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Self-testing infrastructure-as-code

May 31, 2018 | DevOps

Self-testing infrastructure-as-code

As traditional operations has embraced the concept of code, it has benefited from ideas already prevalent in developer circles such as version control. Version control brings the benefit that not only can you see what the infrastructure was, but you can also get reviews of changes by your peers before the change is made live; known to most developers as Pull Request (PR) reviews.

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Testing a Spark Application

May 9, 2017 | Cassandra

Testing a Spark Application

Data analytics isn’t a field commonly associated with testing, but there’s no reason we can’t treat it like any other application. Data analytics services are often deployed in production, and production services should be properly tested. This post covers some basic approaches for the testing of Cassandra/Spark code. There will be some code examples, but the focus is on how to structure your code to ensure it is testable!

 

This blog is written exclusively by the OpenCredo team. We do not accept external contributions.

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Data Analytics using Cassandra and Spark

March 23, 2017 | Cassandra, Data Analysis, Data Engineering

Data Analytics using Cassandra and Spark

In recent years, Cassandra has become one of the most widely used NoSQL databases: many of our clients use Cassandra for a variety of different purposes. This is no accident as it is a great datastore with nice scalability and performance characteristics.

However, adopting Cassandra as a single, one size fits all database has several downsides. The partitioned/distributed data storage model makes it difficult (and often very inefficient) to do certain types of queries or data analytics that are much more straightforward in a relational database.

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Simulating GitHub OAuth2 Login for Tests with JUnit, Webdriver & Hoverfly: Record, Sanitise, Playback and Assert

September 21, 2016 | DevOps

Simulating GitHub OAuth2 Login for Tests with JUnit, Webdriver & Hoverfly: Record, Sanitise, Playback and Assert

Sometimes, it can be difficult to write automated tests for parts of your application due to complexities introduced by an external dependency. It may be flaky or have some sort of rate limiting, or require sensitive information which we don’t want to expose outside of our production environment. To get around this, teams might take the approach of manually stubbing the service or using mocks – but the former is tedious and error prone, whereas the latter doesn’t test collaboration at all.

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Patterns of Successful Cassandra Data Modelling

September 6, 2016 | Cassandra

Patterns of Successful Cassandra Data Modelling

A growing number of clients are asking OpenCredo for help with using Apache Cassandra and solving specific problems they encounter. Clients have different use cases, requirements, implementation and teams but experience similar issues. We have noticed that Cassandra data modelling problems are the most consistent cause of Cassandra failing to meet their expectations. Data modelling is one of the most complex areas of using Cassandra and has many considerations.

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You Are Ignoring Non-­functional Testing

June 15, 2016 | Software Consultancy

You Are Ignoring Non-­functional Testing

It’s as simple as that – and as a consultant, it’s a problem I see all the time. Testing is always focused on functional testing. Non-functional testing, by comparison, is treated like a second class citizen. This means that functional requirements get refined, and non-functional requirements are ignored until the very end.

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Test Automation Concepts – Automated email testing

March 29, 2016 | Software Consultancy

Test Automation Concepts – Automated email testing

Raise your test coverage with automated email testing

Acceptance test suites generally are used for UI and API testing, and we have covered both these approaches in our Test Automation Quickstart project. However, an application may, for example, send registration or expiration warning emails. Often, tests related to this are left to manual testing, instead of putting them into an automated test suite.

However, there’s no need to check emails manually: it suffers from all the same problems as other manual testing. It’s slow, expensive, and inconsistent. There are many libraries available to interact with email through code – this post will focus on how to use them within an automated test suite.

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Ruby Web Acceptance Testing Framework

November 23, 2015 | Software Consultancy

Ruby Web Acceptance Testing Framework

Over a year ago, my colleague Tristan posted on the OpenCredo blog about a test automation quick start framework. It’s a prepackaged framework you can clone and get going with testing instantly, rather than wasting your time rebuilding your framework every single project. We have used this framework successfully used on many of our internal projects, and it relies upon a Java, Cucumber-JVM and Selenium stack.

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Test Automation Framework – Quick start

November 4, 2014 | Software Consultancy

Test Automation Framework – Quick start

When starting a project, teams often spend their time re-inventing the ‘automated testing wheel’.  While every project has it’s own challenges and every team it’s own needs, many things exist as common requirements of a flexible test automation framework.

This post introduces an effective Java test framework that can be used to quickly get started with test automation on a Java project.

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Cross platform test automation with Appium, WebDriver and Cucumber-JVM

September 19, 2013 | Software Consultancy

Cross platform test automation with Appium, WebDriver and Cucumber-JVM

This post will give an overview of mobile testing using Appium. We will integrate tests for a native Android application into an existing Cucumber-JVM based set of acceptance tests and demonstrate multi platform testing from a single set of BDD scenarios. The sample code for this can be found here.

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Spring Data Hadoop – Contextual Analysis

July 4, 2013 | Software Consultancy

Spring Data Hadoop – Contextual Analysis

In which situations Spring Data Hadoop (SDH) can add value, and in which situations would it be a poor choice? This article follows on from an objective summary of the features of SDH.

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Withstanding the test of time – Part 2

February 19, 2013 | Software Consultancy

Withstanding the test of time – Part 2

How to create robust tests for Spring based applications

This blog post continues on from Part 1 which discussed types of tests and how to create robust tests. Part 2 will examine techniques to help whip a test suite in to shape and resolve common issues that slow everything down. The approaches in this post will focus on spring based applications, but the concepts can be applied to other frameworks too.

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Withstanding the test of time

December 18, 2012 | Software Consultancy

Withstanding the test of time

The first thing most people think of when they start a project with the good intentions of test driven development is: write a test first. That’s great, and something I would fully encourage. However, diving in to writing tests without forethought, especially on large projects with a lot of developers can lead to new problems that TDD is not going to solve. With some upfront thinking (but not big upfront design!) a large team can avoid problems later down the line by considering some important and desirable traits of a large and rapidly changing test suite.

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Deploying Neo4j Graph Database Server across AWS regions with Puppet

August 16, 2012 | Neo4j

Deploying Neo4j Graph Database Server across AWS regions with Puppet

neo4jIt’s been more than a year now since I rolled out Neo4j Graph Database Server image in Amazon EC2.

In May 2011 the version of Neo4j was 1.3 and just recently guys at Neo Technology published version 1.7.2 so I thought now is the time to revisit this exercise and make fresh AMIs available.
Last year I created Neo4j AMI manually in one region then copied it across to the remaining AWS regions. Due to the size of the AMI and the latency between regions this process was slow.

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Practical behaviour driven development – Maintainable Acceptance Tests

February 3, 2012 | Software Consultancy

Practical behaviour driven development – Maintainable Acceptance Tests

Behaviour driven development (BBD)

Creating maintainable acceptance test

In this post we will look at the creation of a suite of maintainable acceptance tests, identifying some key issues as encountered on real projects and suggesting solutions.This post assumes some knowledge of behaviour driven development (BDD). If you are new to this concept, I’d recommend Dan North’s blog as a starting point, particularly his post introducing the concept of BDD.The idea of human readable acceptance testing championed by BDD enthusiasts is one that continues to grow in popularity, and it’s easy to see why.

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A Pragmatic Introduction to Machine Learning for DevOps Engineers

January 23, 2018 | Data Engineering, DevOps

A Pragmatic Introduction to Machine Learning for DevOps Engineers

Machine Learning is a hot topic these days, as can be seen from search trends. It was the success of Deepmind and AlphaGo in 2016 that really brought machine learning to the attention of the wider community and the world at large.

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Easy API Simulation with Hoverfly JUnit Rule

March 17, 2016 | Software Consultancy

Easy API Simulation with Hoverfly JUnit Rule

In order to be able to regularly release an application, your automated tests must be set up to give you fast and reliable feedback loop. If bugs are only found during a long and expensive multi-service or end-to-end test run, it can be a hinderance to fast delivery. Unfortunately I have often seen this problem in development environments: a huge suite of clunky, flaky and slow end-to-end tests which test the full functionality of the application as opposed to being more lightweight and reflecting basic user journeys. This produces the “ice cream cone” anti-pattern of test coverage, where unit tests aren’t providing the kind of coverage and feedback they need to.

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What you might have missed in Kubernetes 1.22 release

December 5, 2021 | Cloud, Kubernetes

What you might have missed in Kubernetes 1.22 release

Kubernetes’ second release in 2021, version 1.22, has been out for a little while now and with 1.23 on its way, we thought we’d take a look back. Kubernetes 1.22 was a highly comprehensive release with 53 enhancements in all three graduation levels: 13 features have graduated to stable, 24 enhancements reached beta status, and 16 new features have been accepted into the alpha stage. 

The latest version has some noteworthy security features such as running Kubelet without root access, pod security policies, and seccomp. There are also a couple of deprecated and removed APIs. In this blog, we’ll discuss the significant changes in v1.22, as well as how to handle the removed APIs.

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Exploring How Policy-as-Code and OPA Fit into the K8s World

November 4, 2021 | Kubernetes

Exploring How Policy-as-Code and OPA Fit into the K8s World

We always read that ‘security is everyone’s responsibility’. For any organisation, big or small, security should always be the primary concern—not a mere afterthought. In terms of Kubernetes, securing a cluster is challenging because it has so many moving parts and, apart from securing our Kubernetes environment, we also want to control what an end-user can do in our cluster.

To achieve these goals, we can start with the built-in features provided by Kubernetes like Role-Based Access Control (RBAC), Network Policies, Secrets Management, and Pod Security Policies (PSP). But we know these features are not enough. For example, we may want specific policies like ‘all pods must have specific labels’. And even if we have the policies in place, the next big question is how to enforce them on our Kubernetes cluster in an easy and repeatable manner.

In this blog post, we’ll address this challenge and other questions pertaining to OPA and how it can integrate into Kubernetes.

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Running the Cloud from your Kubernetes Cluster

September 2, 2021 | Blog, Cloud, Kubernetes

Running the Cloud from your Kubernetes Cluster

In this blog, Stuart compares the new approach of deploying cloud resources as Kubernetes custom resources rather than the (now) typical approach using Terraform – or cloud specific: CloudFormation (AWS), Deployment Manager (GCP). He also identifies what resources are suitable for this approach and which ones are not.

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Kafka vs RabbitMQ: The Consumer-Driven Choice

July 20, 2021 | Blog, Data Engineering, Kafka

Kafka vs RabbitMQ: The Consumer-Driven Choice

Message and event-driven systems provide an array of benefits to organisations of all shapes and sizes. At their core, they help decouple producers and consumers so that each can work at their own pace without having to wait for the other – asynchronous processing at its best.

In fact, such systems enable a whole range of messaging patterns, offering varying levels of guarantees surrounding the processing and consumption options for clients. Take for example the publish/subscribe pattern, which enables one message to be broadcast and consumed by multiple consumers; or the competing consumer pattern, which enables a message to be processed once but with multiple concurrent consumers vying for the honour—essentially providing a way to distribute the load. The manner in which these patterns are actually realised however, depends a lot on the technology used, as each has its own approach and unique tradeoffs. 

In this article we will explore how this all applies to RabbitMQ and Apache Kafka, and how these two technologies differ, specifically from a message consumer’s perspective.

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Running a Terraform Provider with a Debugger

May 19, 2021 | DevOps, Hashicorp, Open Source, Terraform Provider

Running a Terraform Provider with a Debugger

Developing a Terraform provider is a great thing for a company to do as it allows customers to quickly integrate a product with their existing systems with very little friction. During development, occasionally there might be bugs and issues to fix, and it can be quite difficult to work out what is causing them. In this post, I outline how you can attach a debugger such as Delve to a Terraform provider to save time when solving these issues.

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Machine Learning at scale: first impressions of Kubeflow

April 20, 2021 | Data Engineering, Machine Learning, Software Consultancy

Machine Learning at scale: first impressions of Kubeflow

Our recent client was a Fintech who had ambitions to build a Machine Learning platform for real-time decision making. The client had significant Kubernetes proficiency, ran on the cloud, and had a strong preference for using free, open-source software over cloud-native offerings that come with lock-in. Several components were spiked with success (feature preparation with Apache Beam and Seldon for model serving performed particularly strongly). Kubeflow was one of the next technologies on our list of spikes, showing significant promise at the research stage and seemingly a good match for our client’s priorities and skills.

That platform slipped down the client’s priority list before completing the research for Kubeflow, so I wanted to see how that project might have turned out. Would Kubeflow have made the cut?

 

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What is Continuous Verification?

October 15, 2020

What is Continuous Verification?

Continuous Verification is a term that is starting to pop up from time-to-time… but what does it mean? Well… according to Nora Jones and Casey Rosenthal, authors of O’Reilly’s Chaos Engineering books,

 

“Continuous verification (CV) is a discipline of proactive experimentation, implemented as tooling that verifies system behaviors. This stands in contrast to prior common practices in software quality assurance, which favor reactive testing, implemented as methodologies that validate known properties of software. This isn’t to say that prior common practices are invalid or should be deprecated. Alerting, testing, code reviews, monitoring, SRE practices, and the like—these are all great practices and should be encouraged”

 

Over the course of this post, we will unpack this statement: to understand what is behind it and what it might mean for your development process.

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Decision time with AWS Keyspaces

September 22, 2020 | AWS, Blog, Cassandra, Cloud, DevOps, Open Source

Decision time with AWS Keyspaces

With the upcoming Cassandra 4.0 release, there is a lot to look forward to. Most excitingly, and following a refreshing realignment of the Open Source community around Cassandra, the next release promises to focus on fundamentals: stability, repair, observability, performance and scaling.

We must set this against the fact that Cassandra ranks pretty highly in the Stack Overflow most dreaded databases list and the reality that Cassandra is expensive to configure, operate and maintain. Finding people who have the prerequisite skills to do so is challenging.

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Automation of complex IT systems

May 14, 2020 | Blog, DevOps

Automation of complex IT systems

At the time of this post, the UK is making steps to exit from an unprecedented lockdown measures for the Coronavirus. Much of the UK workforce are still making efforts to work-from-home with mainly key workers operating – at risk – in public. Many industries have shut down completely. Consequently, many businesses are reflecting on what happens next and how do we better mitigate future pandemic events?

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It’s 2020, can I have my ML models now?

April 2, 2020 | Machine Learning

It’s 2020, can I have my ML models now?

Recent years have seen many companies consolidate all their data into a data lake/warehouse of some sort. Once it’s all consolidated, what next?

Many companies consolidate data with a field of dreams mindset – “build it and they will come”, however a comprehensive data strategy is needed if the ultimate goals of an organisation are to be realised: monetisation through Machine Learning and AI is an oft-cited goal. Unfortunately, before one rushes into the enticing world of machine learning, one should lay more mundane foundations. Indeed, in data science, estimates vary between 50% to 80% of the time taken is devoted to so-called data-wrangling. Further, Google estimates ML projects produce 5% ML code and 95% “glue code”. If this is the reality we face, what foundations are required before one can dive headlong into ML?

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Why Upgrading to Terraform 0.12+ Should be a Priority

October 3, 2019 | Cloud, DevOps, Hashicorp, Open Source

Why Upgrading to Terraform 0.12+ Should be a Priority

Terraform 0.12 in recent years has emerged as the de facto standard with regards to defining and managing cloud infrastructure. It is one of four primary tools offered by HashiCorp, (Terraform, Vault, Consul and Nomad) and underpins the workflows that make up their Cloud Operating Model.

Since its first release in 2014, the wider Terraform community has embraced frequent releases and this past year has been no exception. HashiCorp announced the release of Terraform 0.12 in May 2019 and as of writing this post the official release is 0.12.9.

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3 Highlights from CloudNative London 2019 (Day 1)

October 1, 2019 | Cloud, Cloud Native, Culture

3 Highlights from CloudNative London 2019 (Day 1)

One of the benefits we have working at OpenCredo (OC) is the opportunity to both attend and speak (although not on this occasion) at conferences. For some of you, this may be pretty common, but OC was actually the first to offer me this as part of a broader learning and development plan.

Cloud-native development and delivery is a core area of expertise for OC and we are always looking for what’s new and interesting in this space. So when I was offered the chance to go to CloudNative London it seemed like a good place to start. With its diversity in topics and technologies, the conference provided a perfect opportunity to collaborate and hear from others in the industry and what they are doing in this space.

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Technology, Kindness and Bananas

August 14, 2019 | Culture, News

Technology, Kindness and Bananas

Here, in our little nook of the internet, we usually write about our experiences of emerging technologies, the tricky coding problems we’ve solved and how we have enhanced our clients’ businesses. We do this because we are very proud of this work. It truly matters.

Today is a little different. Today I’d like to share something a little more personal. Something that brings loneliness, kindness and technology together in an oxytocin-generating, slightly awkward embrace. Because hugs matter too.

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Kafka Connect – Source Connectors: A detailed guide to connecting to what you love.

July 30, 2019 | Blog, Kafka

Kafka Connect – Source Connectors: A detailed guide to connecting to what you love.

Writing your own Kafka source connectors with Kafka Connect. In this blog, Rufus takes you on a code walk, through the Gold Verified Venafi Connector while pointing out the common pitfalls

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Securing Kafka using Vault PKI

February 20, 2019 | DevOps, Hashicorp, Kafka, Open Source

Securing Kafka using Vault PKI

Creating and managing a Public Key Infrastructure (PKI) could be a very straightforward task if you use appropriate tools. In this blog post, I’ll cover the steps to easily set up a PKI with Vault from HashiCorp, and use it to secure a Kafka Cluster.

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The Power of the Architecture-driven Organisation

July 13, 2018 | Software Consultancy

The Power of the Architecture-driven Organisation

As a consultant I often find myself in situations that require tricky problem solving, typically of a technical nature. Yet although it is common to approach a consultancy engagement in terms of its technical context, not all problems have a purely technical solution.

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Heuristics for Identifying Service Boundaries

May 16, 2018 | Microservices

Heuristics for Identifying Service Boundaries

To identify service boundaries, it is not enough to consider (business) domains only. Other forces like organisational communication structures, and – very important – time, strongly suggest that we should include several other criteria in our considerations.

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Microservices Anti-patterns: It’s All About the People

April 18, 2018 | Microservices

Microservices Anti-patterns: It’s All About the People

Quite a few of the anti-patterns we observe today on microservices projects are strongly related to how people approach the problem. Given their nature, these anti-patterns tend to be deeply ingrained and self-sustaining. Addressing them starts with increased awareness and by changing ways of approaching the problem, rather than by the introduction of yet another technical tool or framework.

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[Past event] Goto Nights London Meet Up

We are excited to announce that our Senior DevOps consultant, Maartens Lourens will be speaking at Goto Nights London monthly meet up in April! To join us or find out more information, click here.

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Google Cloud Functions with Terraform

April 5, 2018 | Cloud, DevOps, Hashicorp, Terraform Provider

Google Cloud Functions with Terraform

Google Cloud Functions is the Google Cloud Platform (GCP) function-as-a-service offering. It allows you to execute your code in response to event triggers – HTTP, PubSub and Storage. While it currently only supports Node.js code for execution, it has proved very useful for running low-frequency operational tasks and other batch jobs in GCP.

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Get your -aas in gear: Privatelink and PaaS democratisation on AWS

February 6, 2018 | Cloud

Get your -aas in gear: Privatelink and PaaS democratisation on AWS

Among the many announcements made at Re:Invent 2017 was the release of AWS Privatelink for Customer and Partner services. We believe that the opportunity signalled by this modest announcement may have an impact far broader than first impressions suggest.

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Writing a custom JupyterHub Spawner

January 11, 2018 | Data Engineering

Writing a custom JupyterHub Spawner

The last few years have seen Python emerge as a lingua franca for data scientists. Alongside Python we have also witnessed the rise of Jupyter Notebooks, which are now considered a de facto data science productivity tool, especially in the Python community. Jupyter Notebooks started as a university side-project known as iPython in circa 2001 at UC Berkeley.

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Riak, the Dynamo paper and life beyond Basho

August 8, 2017 | Cassandra

Riak, the Dynamo paper and life beyond Basho

Recently, the sad news has emerged that Basho, which developed the Riak distributed database, has gone into receivership. This would appear to present a problem for those who have adopted the commercial version of the Riak database (Riak KV) supported by Basho.

 

This blog is written exclusively by the OpenCredo team. We do not accept external contributions.

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CockroachDB: First Impressions

June 15, 2017 | Data Engineering

CockroachDB: First Impressions

CockroachDB is a distributed SQL (“NewSQL”) database developed by Cockroach Labs and has recently reached a major milestone: the first production-ready, 1.0 release. We at OpenCredo have been following the progress of CockroachDB for a while, and we think it’s a technology of great potential to become the go-to solution for a having a general-purpose database in the cloud.

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Detecting stolen AWS credential usage with Apache Spark – Webinar Recording

May 22, 2017 | Data Analysis

Detecting stolen AWS credential usage with Apache Spark – Webinar Recording

As a final piece of our recent blog series about Apache Spark on 16 May we have presented details of a use-case about using Spark Structured Streaming to generate real-time alerts of suspicious activity in an AWS-based infrastructure.

 

This blog is written exclusively by the OpenCredo team. We do not accept external contributions.

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[Past event] Webinar: Detecting stolen AWS credential usage with Apache Spark

Join us as we conclude our recent Apache Spark series with a webinar that will explore the use case of “Detecting stolen AWS credential usage with Spark”

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Deploy Spark with an Apache Cassandra cluster

May 2, 2017 | Cassandra, Data Engineering

Deploy Spark with an Apache Cassandra cluster

My recent blogpost I explored a few cases where using Cassandra and Spark together can be useful. My focus was on the functional behaviour of such a stack and what you need to do as a developer to interact with it. However, it did not describe any details about the infrastructure setup that is capable of running such Spark code or any deployment considerations. In this post, I will explore this in more detail and show some practical advice in how to deploy Spark and Apache Cassandra.

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New Blog Series: Spark – The Pragmatic Bits

April 25, 2017 | Cassandra, Data Analysis, Data Engineering

New Blog Series: Spark – The Pragmatic Bits

Apache Spark is a powerful open source processing engine which is fast becoming our technology of choice for data analytic projects here at OpenCredo. For many years now we have been helping our clients to practically implement and take advantage of various big data technologies including the like of Apache Cassandra amongst others.

 

 

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Google Cloud Spanner: our first impressions

March 7, 2017 | Data Analysis, GCP

Google Cloud Spanner: our first impressions

Google has recently made its internal Spanner database available to the wider public, as a hosted solution on Google Cloud. This is a distributed relational/transactional database used inside for various Google projects (including F1, the advertising backend), promising high throughput, low latency and 99.999% availability. As such it is an interesting alternative to many open source or other hosted solutions. This whitepaper gives a good theoretical introduction into Spanner.

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Everything you need to know about Cassandra Materialized Views

February 16, 2017 | Cassandra

Everything you need to know about Cassandra Materialized Views

One of the default Cassandra strategies to deal with more sophisticated queries is to create CQL tables that contain the data in a structure that matches the query itself (denormalization). Cassandra 3.0 introduces a new CQL feature, Materialized Views which captures this concept as a first-class construct.

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Event Replaying with Hazelcast Jet

February 13, 2017 | Data Engineering

Event Replaying with Hazelcast Jet

One of the stated intentions behind the design of Java 8’s Streams API was to take better advantage of the multi-core processing power of modern computers. Operations that could be performed on a single, linear stream of values could also be run in parallel by splitting that stream into multiple sub-streams, and combining the results from processing each sub-stream as they became available.

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[Past event] OOP Konferenz 2017

Join Andrew Morgan  and Daniel  Bryant at OOP Conference 2017! By combining software and business, OOP Conference 2017 is the meeting point for people who work primarily in the enterprise environment. Technical experts (architects, developers, business analysts, and testers), technical (project) managers and leaders gain an excellent view on the state-of-the-art in modern software engineering. […]

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Let’s Encrypt and Terraform – Getting free certificates for your infrastructure

January 24, 2017 | Cloud

Let’s Encrypt and Terraform – Getting free certificates for your infrastructure

This blog aims to provide an end to end example of how you can automatically request, generate and install a free HTTPS/TLS/SSL certificate from Let’s Encrypt using Terraform. Let’s Encrypt is a free, automated, and open certificate authority (CA) aiming to make it super easy (and free – did I say free!) for people to obtain HTTPS (SSL/TLS) certificates for their websites and infrastructure. Under the hood, Let’s Encrypt implements and leverages an emerging protocol called ACME to make all this magic happen, and it is this ACME protocol that powers the Terraform provider we will be using. For more information on how Let’s Encrypt and the ACME protocol actually work, please see how Let’s Encrypt works.

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How to TDD FizzBuzz with JUnit Theories

January 13, 2017 | Software Consultancy

How to TDD FizzBuzz with JUnit Theories

The notorious FizzBuzz interview test was originally proposed as a way of weeding out candidates for programming jobs who – to put it bluntly – couldn’t program. The task is as follows:

Write a program that prints the numbers from 1 to 100. But for multiples of three print “Fizz” instead of the number and for the multiples of five print “Buzz”. For numbers which are multiples of both three and five print “FizzBuzz”.

It turns out that this problem has just enough subtlety about it to cause headaches to anyone who knows the basics but hasn’t learned how to think in nested structures.

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[Past event] Public Sector Show Manchester 2016

Join Us at the Public Sector Show Manchester 2016! We are proud to announce that we are sponsoring and exhibiting at the Public Sector Show Manchester 2016, which will be held on the 22nd of November. The conference is targeted at senior decision makers and managers within central government and the public sector. The Public Sector Show is […]

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[Past event] µCon 2016: The Microservices Conference

Join Daniel Bryant and David Borsos at µCon 2016 on Monday the 7th and Tuesday the 8th of November at CodeNode in London. µCon 2016 is an opportunity to learn about emerging technologies and approaches, share challenges and evolve practices and ideas. Share the challenges you are facing, the technologies you are exploring and the skills […]

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Common Problems with Cassandra Tombstones

September 27, 2016 | Cassandra, Data Engineering

Common Problems with Cassandra Tombstones

If there is one thing to understand about Cassandra, it is the fact that it is optimised for writes. In Cassandra everything is a write including logical deletion of data which results in tombstones – special deletion records. We have noticed that lack of understanding of tombstones is often the root cause of production issues our clients experience with Cassandra. We have decided to share a compilation of the most common problems with Cassandra tombstones and some practical advice on solving them.

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[Past event] HashiCorp Meetup #5

It’s time to put Hashicorp Meetup #5 on your agenda! This time around the Hashicorp Meetup will be taking place on the 15th of September and will be held at the ThoughtWorks office in London. Starting at 6:30pm with pizzas and beers on arrival, guest speaker, Tim Kimball, CTO at Aire labs will be taking […]

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Kubernetes from scratch to AWS with Terraform and Ansible (part 1)

August 26, 2016 | Kubernetes

Kubernetes from scratch to AWS with Terraform and Ansible (part 1)

This post is the first of a series of three tutorial articles introducing a sample, tutorial project, demonstrating how to provision Kubernetes on AWS from scratch, using Terraform and Ansible.

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[Past event] Kubernetes London Meetup

Join us for the Celebration of Kubernetes birthday! This time round for the Kubernetes London meetup we will be celebrating their 1st birthday, and we are excited to announce that our Lead Consultant Bart Spaans will be speaking. The meetup will be hosted at Playtech’s office in London borough of Camden, on the 11th of August. […]

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Key Takeaways from the DevOps Enterprise Summit (#DOES16) EU Conference

July 3, 2016 | DevOps

Key Takeaways from the DevOps Enterprise Summit (#DOES16) EU Conference

Several of us from the OpenCredo team were in attendance at the inaugural EU edition of the DevOps Enterprise Summit conference. We have been big fans of the two previous US versions, and have watched the video recordings of talks (2014, 2015) with keen interest as many of our DevOps transformation clients are very much operating in the ‘enterprise’ space.

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Many improvements in Java 8 API for Akka

June 24, 2016 | Software Consultancy

Many improvements in Java 8 API for Akka

Akka has been designed with a Java API from the very first version. Though widely adopted, as a Java developer I think Akka has been mainly a Scala thing… until recently. Things are changing and Akka is moving to a proper Java 8 support.

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Introducing KubeFuse: A File System for Kubernetes

May 31, 2016 | Kubernetes

Introducing KubeFuse: A File System for Kubernetes

Do you ever wake up and think to yourself: oh geez, Kubernetes is awesome, but I wish I could browse and edit my services and replication controllers using the file system? No? Well, in any case, this is now possible.

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Concursus: Event Sourcing for the Internet of Things

May 10, 2016 | Data Engineering, White Paper

Concursus: Event Sourcing for the Internet of Things

In this technical report, we present Concursus, a framework for developing distributed applications using CQRS and event sourcing patterns within a modern, Java 8-centric, programming model. Following a high-level survey of the trends leading towards the adoption of these patterns, we show how Concursus simplifies the task of programming event sourcing applications by providing a concise, intuitive API to systems composed of event processing middleware.

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Securing Terraform state with Vault

April 2, 2016 | Terraform Provider

Securing Terraform state with Vault

When it comes to automating the creation of infrastructure in cloud providers, Terraform (version at time of writing 0.6.14) has become one of my core go to tools in this space. It provides a fantastic declarative approach to describing the resources you want, and then takes care of making it so for you, keeping track of the state in either a local file or a remote store of some sort. Various bits of sensitive data is often provided as input to terraform.

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React/Redux boilerplate

March 3, 2016 | Software Consultancy

React/Redux boilerplate

In this post, I’ll be sharing some React/Redux boilerplate code that Vince Martinez and I have been developing recently. It’s primarily aimed at developers who are familiar with the React ecosystem, so if you are new to React and/or Redux, you might like to have a look at Getting Started with React and Getting Started with Redux.

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Kotlin: a new JVM language you should try

March 3, 2016 | Software Consultancy

Kotlin: a new JVM language you should try

JetBrains (the people behind IntelliJ IDEA) have recently announced  the first RC for version 1.0 of Kotlin, a new programming language for the JVM. I say ‘new’, but Kotlin has been in the making for a few years now, and has been used by JetBrains to develop several of their products, including Intellij IDEA. The company open-sourced Kotlin in 2011, and have worked with the community since then to make the language what it is today.

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Is it Time for Your ‘Microservices Checkup’?

March 2, 2016 | DevOps, Microservices

Is it Time for Your ‘Microservices Checkup’?

Many of our clients are currently implementing applications using a ‘microservice’-based architecture. Increasingly we are hearing from organisations that are part way through a migration to microservices, and they want our help with validating and improving their current solution. These ‘microservices checkup’ projects have revealed some interesting patterns, and because we have experience of working in a wide-range of industries (and also have ‘fresh eyes’ when looking at a project), we are often able to work alongside teams to make significant improvements and create a strategic roadmap for future improvements.

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Akka Typed brings type safety to Akka framework

January 18, 2016 | Software Consultancy

Akka Typed brings type safety to Akka framework

Last time in this series I summarised all the Akka Persistence related improvements in Akka 2.4. Since then Akka 2.4.1 has been released with some additional bug fixes and improvements so perhaps now is a perfect time to pick up this mini-series and introduce some other new features included in Akka 2.4.x.

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Facebook’s React, and the Signal:Noise Ratio

January 15, 2016 | Software Consultancy

Facebook’s React, and the Signal:Noise Ratio

So, you’ve started to hear a lot about React, the Javascript library developed by Facebook, but is it something you need to investigate? It’s time to distil the signal from the noise, position React amongst its rivals, and provide an indication of where it currently would – and would not – be a suitable fit.

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The Seven Deadly Sins of Microservices (Redux)

January 8, 2016 | Microservices

The Seven Deadly Sins of Microservices (Redux)

Many of our clients are in the process of investigating or implementing ‘microservices’, and a popular question we often get asked is “what’s the most common mistake you see when moving towards a microservice architecture?”. We’ve seen plenty of good things with this architectural pattern, but we have also seen a few recurring issues and anti-patterns, which I’m keen to share here.

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OpenCredo is now an Amazon Web Services APN Consulting Partner
(Spring) Booting Hazelcast

December 1, 2015 | Software Consultancy

(Spring) Booting Hazelcast

This post introduce some of the basic features of Hazelcast, some of its limitations, how to embed it in a Spring Boot application and write integration testings. This post is intended to be the first of a series about Hazelcast and its integration with Spring (Boot). Let’s start from the basics.

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RAML 1.0 promotes reusability and standardisation

November 25, 2015 | Microservices

RAML 1.0 promotes reusability and standardisation

In May a 1.0 release of RAML (RESTful API Markup Language) has been announced delivering a few much welcome additions in the RAML 1.0 specification. This major release marks an important milestone in the evolution of RAML and indicates the team behind the specification is confident this release delivers the comprehensive set of tools for developing RESTful APIs. I’ve been using RAML 0.8 for several months now and have enjoyed the simplicity and productivity it offers for designing and documenting APIs. I must say I’m quite pleased with the changes introduced in the new release and would like to review those I consider particularly useful.

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Implementing HAL hypermedia REST API using Spring HATEOAS

November 1, 2015 | Microservices

Implementing HAL hypermedia REST API using Spring HATEOAS

To use or not to use hypermedia (HATEOAS) in a REST API, to attain the Level 3 of the famous Richardson Maturity Model. This is one of the most discussed subjects about API design.
The many objections make sense (“Why I hate HATEOAS“, “More objections to HATEOAS“…)
. The goal of having fully dynamic, auto-discovering clients is still unrealistic (…waiting for AI client libraries).

However, there are good examples of successful HATEOAS API. Among them, PayPal.

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JavaOne: Building a Microservice Development Ecosystem (Video)

October 31, 2015 | Microservices

JavaOne: Building a Microservice Development Ecosystem (Video)

Microservices: Some Assembly Required

Over the past few weeks I’ve been writing an OpenCredo blog series on the topic of “Building a Microservice Development Ecosystem”, but my JavaOne talk of the same title crept up on me before I managed to finish the remaining posts. I’m still planning to finish the full blog series, but in the meantime I thought it would be beneficial to share the video and slides associated with the talk, alongside some of my related thinking. I’ve been fortunate to work on several interesting microservice projects at OpenCredo, and we’re always keen to share our knowledge or offer advice, and so please do get in touch if we can help you or your organisation.

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What’s new in Akka Persistence 2.4

October 28, 2015 | Software Consultancy

What’s new in Akka Persistence 2.4

Let’s have a quick look at the most interesting changes and new features that are now available to Akka users. As there are many new features to highlight in the new Akka release I will focus on those related to Akka Persistence first and cover other areas in a separate post.

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Our Thoughts on DevOps and Cloud at JAX London

October 18, 2015 | Cloud, DevOps

Our Thoughts on DevOps and Cloud at JAX London

DevOps, Cloud and Microservices: “All Hail the Developer King/Queen”

Last week Steve Poole and I were once again back at the always informative JAX London conference talking about DevOps and the Cloud. This presentation built upon our previous DevOps talk that was presented last year, and focused on the experiences that Steve and I had encountered over the last year (the slides for our 2014 “Moving to a DevOps” mode talk can be found on SlideShare, and the video on Parleys).

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Join us at the Inaugural ContainerSched Conference

October 16, 2015 | Software Consultancy

Join us at the Inaugural ContainerSched Conference

Interested in Containers and Schedulers?

OpenCredo is helping Skillsmatter with the organisation of the inaugural ContainerSched conference, and we were last night in attendance at CodeNode, working our way to finalising the program alongside the Skillsmatter team. I’m pleased to say that the provisional lineup looks great (speaker acceptance emails are being sent out over the next few days), and so I wanted to share the details of some of the great content we have confirmed already.

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The curse of correlation

October 7, 2015 | Software Consultancy

The curse of correlation

How correlated estimates make prediction in IT hard.

It’s well known that predicting how long a project/task will take in IT is hard. In this post I’ll address one aspect of this (correlation) and ask what insights a data science perspective can give us about how correlations can make prediction difficult. I’ll explain the problems that correlation poses, give some practical advice for teams & project managers and investigate possible innovations to tooling that might improve matters.

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Microservice Platforms: Some Assembly [Still] Required. Part Two

September 20, 2015 | Microservices

Microservice Platforms: Some Assembly [Still] Required. Part Two

Working Locally with Microservices

Over the past five years I have worked within several projects that used a ‘microservice’-based architecture, and one constant issue I have encountered is the absence of standardised patterns for local development and ‘off the shelf’ development tooling that support this. When working with monoliths we have become quite adept at streamlining the development, build, test and deploy cycles. Development tooling to help with these processes is also readily available (and often integrated with our IDEs). For example, many platforms provide ‘hot reloading’ for viewing the effects of code changes in near-real time, automated execution of tests, regular local feedback from continuous integration servers, and tooling to enable the creation of a local environment that mimics the production stack.

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SaltStack – Using Consul as an External Pillar Source

September 14, 2015 | DevOps, Hashicorp, Open Source

SaltStack – Using Consul as an External Pillar Source

Recently I was working on a project that was using SaltStack for configuration management and Consul for service discovery. It occurred to me that using Consul’s key/value store would be great place to store data needed for my Salt runs, but unfortunately Consul was not supported in SaltStack as an official data store at that point in time. Being an open source project however, this provided an excellent opportunity to contribute back and this blog post looks to provide some details on how this works, as well as a practical demo on how you can take advantage of Consul as an external data store.

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Microservice Platforms: Some Assembly [Still] Required. Part One

August 26, 2015 | Cloud

Microservice Platforms: Some Assembly [Still] Required. Part One

The challenges of building and deploying microservices

Unless you’ve been living under a rock for the last year, you’ll undoubtedly know that microservices are the new hotness. An emerging trend that I’ve observed is that the people who are actually using microservices in production tend to be the larger well-funded companies, such as Netflix, Gilt, Yelp, Hailo etc., and each organisation has their own way of developing, building and deploying.

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New Tricks With Dynamic Proxies In Java 8 (part 3)

August 18, 2015 | Software Consultancy

New Tricks With Dynamic Proxies In Java 8 (part 3)

In this post, the last in the New Tricks With Dynamic Proxies series (see part 1 and part 2), I’m going to look at using dynamic proxies to create bean-like value objects to represent records. The basic idea here is to have some untyped storage for a collection of property values, such as an array of Objects, and a typed wrapper around that storage which provides a convenient and type-safe access mechanism. A dynamic proxy is used to convert calls on getter and setter methods in the wrapper interface into calls which read and write values in the store.

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Boot my (secure)->(gov) cloud

August 10, 2015 | Cloud, Software Consultancy

Boot my (secure)->(gov) cloud

As a company, we at OpenCredo are heavily involved in automation and devOps based work, with a keen focus on making this a seamless experience, especially in cloud based environments. We are currently working within HMRC, a UK government department to help make this a reality as part of a broader cloud broker ecosystem project. In this blog post, I look to provide some initial insight into some of the tools and techniques employed to achieve this for one particular use case namely:
With pretty much zero human intervention, bar initiating a process and providing some inputs, a development team from any location, should be able to run “something”, which, in the end, results in an isolated, secure set of fully configured VM’s being provisioned within a cloud provider (or providers) of choice.

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Embracing Disruptive Innovation: OpenCredo Partners with Google

August 5, 2015 | Cloud, GCP, Kubernetes

Embracing Disruptive Innovation: OpenCredo Partners with Google

Why OpenCredo partnered with Google

Recently OpenCredo chose to partner with Google in order to share knowledge and resources around the Google Cloud Platform offerings. Our clients come in many shapes and sizes, but typically all of them realise three disruptive truths of the modern IT industry: the (economic) value of cloud; the competitive advantage of continuous delivery; and the potential of hypothesis and data-driven product development to increase innovation (as popularised by the Lean Startup / Lean Enterprise motto of ‘build, measure, learn’).

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New Tricks with Dynamic Proxies in Java 8 (part 2)

July 14, 2015 | Software Consultancy

New Tricks with Dynamic Proxies in Java 8 (part 2)

Building simple proxies

In the previous post I introduced Java dynamic proxies, and sketched out a way they could be used in testing to simplify the generation of custom Hamcrest matchers. In this post, I’m going to dive into some techniques for implementing proxies in Java 8. We’ll start with a simple case, and build up towards something more complex and full-featured.

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A deep dive into Angular 2.0

July 8, 2015 | Software Consultancy

A deep dive into Angular 2.0

I was quite excited around autumn last year when Google started to work on a new version of Angular (Angular 2.0) which promised to revolutionise web development. There were rumours that Angular 2.0 wouldn’t be backward compatible with its predecessor, and would be written in Google’s AtScript which is a JavaScript based language on top of Microsoft’s TypeScript. The lack of backwards compatibility raised some concerns, especially for the clients that we had used Angular at. But, lets not get ahead of ourselves here….

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Asynchronous Cloud bootstrapping with Terraform, Cloud-Init & Puppet

June 23, 2015 | Cloud, DevOps, Terraform Provider

Asynchronous Cloud bootstrapping with Terraform, Cloud-Init & Puppet

Working with OpenCredo clients, I’ve noticed that even if you are one of the few organisations that can boast ‘Infrastructure as Code’, perhaps it’s only true of your VMs, and likely you have ‘bootstrap problems’. What I mean by this, is that you require some cloud-infrastructure to already be in place before your VM automation can go to work.

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How to Write Your Own Apache Mesos Framework?

February 16, 2015 | Software Consultancy

How to Write Your Own Apache Mesos Framework?

Apache Mesos is often explained as being a kernel for the data-centre; meaning that cluster resources (CPU, RAM, …) are tracked and offered to “user space” programs (i.e. frameworks) to do computations on the cluster.

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Traits with Java 8 Default Methods

January 30, 2015 | Software Consultancy

Traits with Java 8 Default Methods

When I first started programming in Scala a few years ago, Traits was the language feature I was most excited about. Indeed, Traits give you the ability to compose and share behaviour in a clean and reusable way. In Java, we tend deal with the same concerns by grouping crosscutting behaviour in abstract base classes that are subsequently extended every time we need to access shared behaviour in part or in total.

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November 19, 2014 | Microservices

The 7 Deadly Sins of Microservices

Undeniably, there is a growing interest in microservices as we see more organisations, big and small, evaluating and implementing this emerging approach. Despite its apparent novelty, most concepts and principles underpinning microservices are not exactly new – they are simply proven and commonsense software development practices that now need to be applied holistically and at a wider scale, rather than at the scale of a single program or machine. These principles include separation of concerns, loose coupling, scalability and fault-tolerance.

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Experiences with Spring Boot

February 24, 2014 | Cloud Native, Microservices

Experiences with Spring Boot

Last year some of us attended the London Spring eXchange where we encountered a new and interesting tool that Pivotal was working on: Spring Boot. Since then we had the opportunity to see what it’s capable of in a live project and we were deeply impressed.

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New features in Cassandra 2.0 – Lightweight Transactions on Update

February 17, 2014 | Cassandra

New features in Cassandra 2.0 – Lightweight Transactions on Update

In our previous posts we gave an overview of Cassandra’s new compare-and-set (lightweight transaction) commands and a more detailed look into the API for using them when inserting new rows into the database.

In this third post, we are going to cover update statements. We recommend reading the previous posts, as there are some details which are the same for inserts and updates which are not repeated here.

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Cucumber Android vs Appium with cucumber jvm

January 28, 2014 | Software Consultancy

Cucumber Android vs Appium with cucumber jvm

A while ago I published this blog post about writing tests for mobile applications using Appium and cucumber-jvm.

In this post, I will look at an alternative approach to testing an Android native application using Cucumber-Android.

Throughout the post I will draw comparisons between Appium and Cucumber-Android, the goal being to determine the best approach for testing an android application using Cucumber. I will focus on the ease of configuration and use, speed of test runs and quality of reporting.

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New features in Cassandra 2.0 – More on Lightweight Transactions

December 2, 2013 | Cassandra

New features in Cassandra 2.0 – More on Lightweight Transactions

Perhaps the most important of Cassandra’s selling points is its completely distributed architecture and its ability to easily extend the cluster with virtually any number of nodes. Implementing a classical RDBMS-style transaction consisting of “put locks on the database, modify the data, then commit the transaction”-style operations are simply not feasible in such an architecture (i.e. that doesn’t scale well).

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New features in Cassandra 2.0 – Lightweight Transactions and Triggers

November 14, 2013 | Cassandra

New features in Cassandra 2.0 – Lightweight Transactions and Triggers

Cassandra 2.0 was released in early September this year and came with some interesting new features, including “lightweight transactions” and triggers.

Despite the rising interest in the various non-relational databases in recent years, there are still numerous use-cases for which a relational database system is a better choice. The latest major release of Cassandra (version 2.0) provides some interesting features that aim to close this gap, and offers its fast and distributed storage engine enhanced with new options that will make users’ lives easier.

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OpenCredo consultants Nicki Watt and Tareq Abedrabbo speak at Graph Connect London
Configuration Management with Flexible Contexts

August 2, 2013 | Software Consultancy

Configuration Management with Flexible Contexts

Configuration management was born in the pre-cloud era. Remember the days when acquiring a super powerful multi core server felt like winning the jackpot? Infrastructure was a slightly different place back then. Yet for all the recent developments in DevOps, its legacy is still with us.

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Graph Cafe London
Chris Hedley of OpenCredo talk on extending Cloud Foundry available
Model Matters: Graphs, Neo4j and the Future

February 25, 2013 | Neo4j

Model Matters: Graphs, Neo4j and the Future

As part of our work, we often help our customers choose the right datastore for a project. There are usually a number of considerations involved in that process, such as performance, scalability, the expected size of the data set, and the suitability of the data model to the problem at hand.

This blog post is about my experience with graph database technologies, specifically Neo4j. I would like to share some thoughts on when Neo4j is a good fit but also what challenges Neo4j faces now and in the near future.

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A dive into saltstack

January 10, 2013 | DevOps

A dive into saltstack

Recently I have started looking into SaltStack as a solution that does both config management and orchestration. It is a relatively new project started in 2011, but it has a growing fanbase among Sys Admins and DevOps Engineers. In this blog post I will look into Salt as a promising alternative, and comparing it to Puppet as a way of exploring its basic set of features.

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The factors pushing many organisations towards Continuous Delivery with Infrastructure as Code and what’s next…

January 7, 2013 | Software Consultancy

The factors pushing many organisations towards Continuous Delivery with Infrastructure as Code and what’s next…

The practice of continuous integration in which build servers are used to build and perform testing of code is now widespread and mainstream.

While not all teams have adopted continuous integration effectively, its increasing adoption has led many to start to look for additional opportunities to improve the cost, quality and speed of delivery with which software targeted to meet business needs can be released into production environments.

Traditionally Continuous Integration addresses the question of “does the software build and pass our unit and integration test suites?”. This is often insufficient.

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Esper Extensions – Implementing Custom Aggregation Function

March 21, 2012 | Software Consultancy

Esper Extensions – Implementing Custom Aggregation Function

Event processing Language (EPL) enables us to write complex queries to get the most out of our event stream in real time, using SQL-like syntax.

EPL allows us to use full power of aggregation of the high volume event stream to get required results with the minimal latency. In this blog we are going to explore some aspects of numerical aggregation of data with high precision BigDecimal values. We will also demonstrate how you can add you own aggregation function to Esper engine and use them in EPL statements.

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48 hours – The Pursuit of Proper Performance

February 13, 2012 | Software Consultancy

48 hours – The Pursuit of Proper Performance

Recently we were approached by a client to do some performance testing of the web application they had written. The budget allowed two days for this task. Ok. No problem. Yes, we can. Naturally I had one or another question though…

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A Simple Introduction to Complex Event Processing – Stock Ticker End-to-End Sample

February 8, 2012 | Data Analysis, Data Engineering

A Simple Introduction to Complex Event Processing – Stock Ticker End-to-End Sample

Most of the important players in this space are large IT corporations like Oracle and IBM with their commercial (read expensive) offerings.

While most of CEP products offer some great features, it’s license model and close code policy doesn’t allow developers to play with them on pet projects, which would drive adoption and usage of CEP in every day programming.

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Neo4j Super Nodes and Indexed Relationships, Part II

November 4, 2011 | Neo4j

Neo4j Super Nodes and Indexed Relationships, Part II

 Neo4j Super Nodes

In the previous post we compared the performance of fetching relationships from densely populated nodes using Neo4j native store and using lucene index.

We’ve seen that we can fetch the small subset of relationships from a super-node (containing ~1M relationships in total) directly from the Lucene index, the performance of the first run (cold-caches) is better then using the Neo store directly. The subsequent runs with caches warmed up show comparable performance, slightly in favor of direct Neo store fetching, sue to low level cache optimizations.

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Aleksa Vukotic of OpenCredo to talk on Neo4J and Spring at Neo4J user group