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Keycloak SSO Integration into jBPM and Drools Workbench


Introduction Single Sign On (SSO) and related token exchange mechanisms are becoming the most common scenario for the authentication and authorization in different environments on the web, specially when moving into the cloud. This article talks about the integration of Keycloak with jBPM or Drools applications in order to use all the features provided on Keycloak. Keycloak is an integrated SSO ...

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Java Remote Debug for Applications Running in Kubernetes


Kubernetes 1.2 was just released and is quickly becooming the defacto cluster management solution for containers (Docker, Rocket, Hyper, etc). Check it out if you haven’t already – here are some interesting tidbits about the 1.2 release: Cluster can now scale to 30,000 containers per cluster Graceful shutdown of nodes, transitioning to other running nodes in the cluster Custom defined ...

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Logging Requests to Elasticsearch


This is something I wanted to write down for years but never got down to completing the post. It can help you a lot with certain Elasticsearch setups by answering two questions using the slow log. Is my application talking to Elasticsearch? What kind of queries are being built by my application? A while ago I helped a colleague on ...

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Micro-services for performance


Overview Microservices is a buzz word at the moment. Is it really something original or based on established best practices. There are some disadvantages to the way micro-services have been implemented, but can these be solved? Component testability and consistency Once you have assembled a large system, it can be hard to impossible to profile where the highest delays come ...

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Building GORM Criteria Queries Dynamically


I originally wrote most of the queries in the spring-security-ui plugin using HQL because I find it more intuitive than criteria queries, but HQL only works with Hibernate and relational databases. A pull request updated the queries to use criteria queries to allow the plugin to be used with NoSQL datastores, but one query didn’t fit the programming style that ...

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A tale of troubleshooting database performance, with Cassandra and sysdig


Gianluca Bordello is an engineering manager at Sysdig, where he wears many hats. He’s a core developer of sysdig, an open source troubleshooting tool for Linux and containers, and spends his days dealing with backend development, performance analysis and cloud infrastructure management. Introduction As far as databases go, I’m a  huge fan of Cassandra: it’s an incredibly powerful and flexible ...

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Looking at DiagnosticCommandMBean in JConsole and VisualVM


I’ve used JConsole for many years as a suitable generic JMX client. This tool is generally available with the Oracle JDK and is easy to use. In terms of JMX interaction, the most significant advantage of JConsole over VisualVM is that JConsole comes with a built-in MBeans tab while a plugin must be applied for this same functionality in VisualVM. ...

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Fundamental refactoring vs elaborative refactoring


Two types of structure Historian Benedict Anderson once wrote that, “All communities larger than primordial villages of face-to-face contact … are imagined.” In a sense, both class dependencies and package dependencies, too, are imagined. They’re not really there. And yet we expend vast energies in managing them. What motivates us to grapple with hallucinatory monsters? Well, this blog’s primary assumption ...

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