malli VS honeysql

Clojure's lazy sequences by default are wonderful ergonomically, but it provides many ways to use strict evaluation if you want to. They aren't really a hassle either. I've been doing Clojure for the last few years and have a few grievances, but overall it's the most coherent, well thought out language I've used and I can't recommend it enough.

There is the issue of startup time with the JVM, but you can also do AOT compilation now so that really isn't a problem. Here are some other cool projects to look at if you're interested:

Malli: https://github.com/metosin/malli

Babashka: https://github.com/babashka/babashka

Clerk: https://github.com/nextjournal/clerk

BREAKING: walking a :schema passes children instead of [id] to the walker function #884

When you get to larger, more complex validations, I'd recommend checking out Malli or Spec.

for specs, you can try malli - feels pretty well supported and full featured: https://github.com/metosin/malli (i'm not 100% sure how popular it is for others, but I use it on my personal projects)

Have you tried malli: Data-driven Schemas for Clojure/Script?

All that being said, I particularly use malli and I don't find anything to complain about. There is a very nice and sound ecosystem being built around it (malli-ts is one of my contributions to it, but still in early development stages). I highly recommend reading its README, very informative stuff.

Any large codebase can be broken up into small isolated components that can be reasoned about independently. This is how you structure Clojure projects if you want them to be maintainable. Clojure inherently encourages doing this by defaulting to immutability. The contract between components is the data being passed to the component and returned by it. Using Malli schemas at the edges of the components is a typical approach to documenting their APIs https://github.com/metosin/malli

I see the fact that people often end up creating large and tightly coupled monolithic codebases in static languages as a negative aspect of static typing. Such codebases are difficult to reason about even if you have guarantees that the types align. Ultimately, you need to understand the relationships in code, and how they relate to business logic. The more coupling an application has the harder it becomes to reason about it as a whole.

Ideally, I think applications should be structured as a bunch of Lego blocks that can be composed together. Each component should encapsulate some functionality, and then the flow of the business logic should bubble up to the top and expressed in how these components are chained together.

Uhhh spec has existed for a long time and before that, schema Nowadays we also have the excellent malli. If his codebase is full of functions where the shape of the data isn’t obvious, isn’t documented and isn’t specified in a specific/schema, that’s on him and his bad coding practices and really no different from passing data in other dynamic languages. A class by itself (without additional effort) only gives you field names.

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.