Tapestry is a framework for writing (postgres)SQL queries and (pgTAP) tests using Jinja templates. It helps you write reusable SQL code and ensures that your pgTAP tests are testing the exact same SQL queries that are actually run by your application.
Tapestry is written in Rust but it can be used with applications written in any programming language. It's purely a command line tool that renders Jinja templates into SQL files. How to load the resulting SQL code into memory and use it at runtime is entirely up to the application.
This approach of loading SQL from files is not new. There are existing
libraries such as yesql,
hugsql (Clojure),
aiosql (Python) etc. that
provide excellent abstractions for it. In absence of such a lib for
the language of your choice, it shouldn't take more than a few lines
of code to implement a simple file loader. In Rust apps, I simply use
the include_str! macro.
One limitation is that tapestry can only be used with PostgreSQL,
because of the tight coupling with pgTAP.
You may find this tool useful if,
-
you prefer direct SQL queries over ORMs or query builders to interact with RDBMS from application code
-
you are not averse to the idea of having (reasonable amount of) business logic inside SQL queries
In fact, if you have had concerns about point 2 i.e. having business
logic in SQL queries, perhaps tapestry addresses some of those
concerns. Learn more about the
rationale behind
this tool.
Tapestry is a work in progress. But I am presently using it in my personal project so it has been tested for the basic use cases. A working example is also included in the repo which you may try out.
The first tag/version is yet to be created and released.
You can install tapestry directly from github,
cargo install --git https://github.com/naiquevin/tapestry.gitThere's an additional dependency on pg_format for formatting the generated SQL files. It's recommended, but not a hard requirement.
Detailed documentation about tapestry can be found
here
Notable sections:
MIT (See LICENSE).