Rust 拡張機能の作成

git clone https://github.com/villagesql/vsql-rust-sdk
cd vsql-rust-sdk
cargo install --path cargo-vsql

cargo new --lib vsql_my_extension
cd vsql_my_extension
cargo add villagesql

[lib]
crate-type = ["cdylib"]

{
  "name": "vsql_my_extension",
  "version": "0.1.0",
  "description": "My VillageSQL extension",
  "author": "Your Name",
  "license": "GPL-2.0"
}

use villagesql::{InValue, VdfReturn};

fn my_func_impl(args: &[InValue]) -> VdfReturn {
    match args.first() {
        Some(InValue::String(s)) => VdfReturn::string(s.to_uppercase()),
        Some(InValue::Null) | None => VdfReturn::null(),
        _ => VdfReturn::error("my_func: expected a STRING argument"),
    }
}

villagesql::extension! {
    funcs: [
        villagesql::func!(my_func_impl, "my_func", [villagesql::Type::String] -> villagesql::Type::String),
    ]
}

INSTALL EXTENSION vsql_my_extension;
SELECT my_func('hello');
SELECT my_func(NULL);
UNINSTALL EXTENSION vsql_my_extension;

export VillageSQL_BUILD_DIR=/path/to/villagesql/build
cargo vsql test --record
cargo vsql test

cargo vsql install

INSTALL EXTENSION vsql_my_extension;
SELECT * FROM INFORMATION_SCHEMA.EXTENSIONS WHERE EXTENSION_NAME = 'vsql_my_extension';
SELECT my_func('hello');
-- → HELLO