component VS honeysql

* Lifecycle management: Mount, Integrant or Component (https://github.com/tolitius/mount https://github.com/weavejester/integrant and https://github.com/stuartsierra/component)

When you start to have multiple stateful components (the database, the HTTP server, your Redis connection, a page cache, etc.), then you'll want to use a library like component that manages their (inter-)dependencies and provides a consistent notion of lifecycle.

Today I released a new version of Reveal Pro — dev.vlaaad/reveal-pro {:mvn/version "1.3.308"} — that adds sticker integration for system libraries such as mount, component and integrant!

I agree with the main sentiment from the article. Although I do think they are discussing Inversion of control more-so than dependency injection.

One of my first languages was .net and I was never able to really understand DI in that context that well.

Actually using javascript and ducktyping made me understand what it actually was.

I remember a .net job interview where I had to write a micro-service and opted to construct the dependency graph in the main function initialising "all" the classes there. Instead of discussing the pro's and con's of that approach they berated me for not using a DI framework (No I did not land that job, but in hindsight it was the most expensive job interview I've ever had. The room was filled with 8 developers going over my code).

The main thing the article glosses over is state. something people with a functional background hide from. But if you look at something like the httpclient in .net. I think it took the .net world like 10 years to start using the httpclient properly. Scope and lifetime of those kind of objects are important. managing connection pools, retry state, throttling or the incoming http request. DI does make that kind of thing easieR (I'm not saying it makes it better)

Look at clojure's component(https://github.com/stuartsierra/component), I'm not a clojure expert by far. But it is kinda DI/IOC in a functional language.

In closing we can agree that it is underused in the right places and overused in the wrong ones.

https://github.com/stuartsierra/component#no-function-should-take-the-entire-system-as-an-argument

Yeah like I mentioned I'm not like super sold on the everything-should-be-an-actor paradigm, but I find value in DDD + a light implementation of Components (similar to stuartsierra/component).

https://github.com/stuartsierra/component for managing components lifecycles in projects

I recall using korma way back I and I don’t recall it being terrible but I would say https://github.com/seancorfield/honeysql has very much superseded it by this point… (but I can see how that might not be obviously clear if one is to look at superficial metrics like GitHub stars for example…)

Joins can certainly work in a data format like YAML. For an example, see Honey SQL from the Clojure community [0] (though without something to contrast strings like Clojure's keywords, you miss out on the automatic parameterization).

You mentioned moving JOINs around, so I'll mention that if represented as structured data, you can move any of the top level components around, so you could more closely follow the "true order of SQL" [1]. For example, I would love to be able to put FROM before SELECT in all or almost all cases. There's also being able to share and add to something like a complicated WHERE clause, where essentially all programming languages have built-in facilities for robustly manipulating ordered and associative data compared to string manipulation, which is not well-suited for the task.

Now don't get me wrong, I don't particularly care for YAML (though it doesn't bother me that much), but as someone who's done their fair share of programmatic SQL creation and manipulation in strings, not having a native way to represent SQL as data is a mistake in my opinion.

0: https://github.com/seancorfield/honeysql#big-complicated-exa...

In Clojure-land, we are also using HoneySQL [1] which has similar characteristics. You are still working within SQL semantics so it's a bit more complicated, but we are doing great complicated things with just maps, no API necessary.

[1] https://github.com/seancorfield/honeysql

using honeysql we can make structured queries as well

As someone else already pointed out, next.jdbc is good for database connectivity (for Postgres and beyond). For composing the queries themselves, I strongly recommend Honey SQL. It lets you represent queries themselves as normal Clojure data structures, just vectors and maps.

Perhaps you're looking for a way of arranging SQL as an AST represented by data structures (or objects) that can be fed to a compiler. HoneySQL[0] is one such implementation of this idea and it makes your general transformation trivial for Clojure programs. You don't need to mess around with string concatenation because you have a predictable and extensible compiler for data structures (which are themselves easily composable/transformable/storable with Clojure) that you can trust to do the right thing. If you're using some weird database or need an esoteric syntax, extending the compiler to your clause is easy to do[1].

[0] https://github.com/seancorfield/honeysql

[1] https://github.com/seancorfield/honeysql#extensibility

https://github.com/seancorfield/honeysql (write SQL without having to write SQL)

I've used it from Clojure, via HoneySQL, so no ORM, no danger of SQL injection. It was really wonderful!

https://github.com/seancorfield/honeysql

I used it to quickly iterate on the development of migration SQL scripts for a MySQL DB, which was running in production on RDS.

I might have switched to H2 DB later, because that was more compatible with MariaDB, but I could use the same Clojure code, representing the SQL queries, because HoneySQL can emit different syntaxes.