Version 4.0 of the RabbitMQ Java Client brings support for runtime metrics. This can be especially useful to know how a client application is behaving. Let's see how to enable metrics collection and how to monitor those metrics on JMX or even inside a Spring Boot application.
The RabbitMQ team is happy to announce the release of version 4.0 of the RabbitMQ Java Client. This new release does not introduce any breaking changes and comes with a bunch of interesting new features.
RabbitMQ is a very extensible message broker, allowing users to extend the server's functionality by writing plugins. Many of the broker features are even shipped as plugins that come by default with the broker installation: the Management Plugin, or STOMP support, to name just a couple. While that's pretty cool, the fact that plugins must be written in Erlang is sometimes a challenge. I decided to see if it was possible to write plugins in another language that targeted the Erlang Virtual Machine (EVM), and in this post I'll share my progress.
AtomizeJS is a JavaScript library for writing distributed programs, that run in the browser, without having to write any application specific logic on the server.
Here at RabbitMQ HQ we spend quite a lot of time arguing. Occasionally, it's about important things, like what messaging really means, and the range of different APIs that can be used to achieve messaging. RabbitMQ and AMQP present a very explicit interface to messaging: you very much have verbs send and receive and you need to think about what your messaging patterns are. There's a lot (of often quite clever stuff) going on under the bonnet but nevertheless, the interface is quite low-level and explicit, which gives a good degree of flexibility. Sometimes though, that style of API is not the most natural fit for the problem you're trying to solve - do you really reach an impasse and think "What I need here is an AMQP-message broker", or do you, from pre-existing knowledge, realise that you could choose to use an AMQP-message broker to solve your current problem?
Recently I saw a tweet saying "ZeroMQ Erlangizes everything!" or some such. While I realise that not everything posted on the web is meant seriously, it does seem there is a stream of similar claims lately that ought to be dammed.
In the article Multi-threading Magic[^1], Pieter Hintjens and Martin Sustrik persuasively explain why concurrency is better served by message-passing than by locks and shared memory. And they are fair, I think, in their analysis -- except for the insinuation that using ZeroMQ transforms your chosen programming language into a domestic Erlang.
Most of us at RabbitMQ HQ have spend time working in a number of functional languages in addition to Erlang, such as Haskell, Scheme, Lisp, OCaml or others. Whilst there is lots to like about Erlang, such as its VM/Emulator, there are inevitably features that we all miss from other languages. In my case, having spent a couple of years working in Haskell before returning to the RabbitMQ fold, all sorts of features are "missing", such as laziness, type classes, additional infix operators, the ability to specify precedence of functions, fewer parenthesis, partial application, more consistent standard libraries and do-notation. That's a fair list, and it'll take me a while to get around to implementing them all in Erlang, but here are two for starters.
