queryweave

queryweave generates the code that lets the clients of an application filter, sort, page through and partially update its data, from a few attributes on your domain model.

The SQL is built on sqlx, sea-query (and so SeaORM) or Diesel, for Postgres, MySQL/MariaDB and SQLite. The query parameters work with the libraries you choose: with serde, they deserialize from a query string read by serde_qs.

The problem it solves

Take a list endpoint: GET /users?username_sw=ad&page=2&page_size=20, which returns the second page of users whose username starts with "ad", in some requested order. To serve it, a layered application usually writes the same idea several times:

the API layer needs query parameters to deserialize, document and validate;
the domain needs a query type that the application logic can pass around without knowing about HTTP or SQL;
the persistence layer needs to turn that query into WHERE, ORDER BY and LIMIT/OFFSET clauses.

Written by hand, these copies drift apart: a field filterable in the API but not in the database, a renamed column that only fails at runtime, a sort option documented but never applied. queryweave writes all three from one description, and checks at compile time that they agree.

How it works

You mark the fields of a root model, usually your domain model, with what can be done with them:

use queryweave_derive::Filters;

#[derive(Filters)]
pub struct UserModel {
    pub id: UserId,

    #[filter(sw, c, ew)] // starts with, contains, ends with
    #[sortable]
    pub username: Username<String>,
}

From this, the domain gets a query type, UsersQueryModel, holding the requested page, sort order and filters (username_sw, username_c, username_ew), as plain data with no database or serializer attached.

Every other layer mirrors the root model. A mirror lists the same fields, under the names that layer uses, and says which libraries its types should work with:

#[derive(Filters)]
#[filters(mirrors = domain::UserModel, serde, utoipa, validator)]
pub struct UserDto {
    #[filter(sw, c, ew)]
    #[sortable]
    pub username: String,
}

The API layer now has UsersQueryParams, which deserializes from the query string, is documented in the OpenAPI schema and validates the page size and sort, and converts into the domain's query with .into(). A field the API names differently maps onto the model's with #[equivalent_field(name)], and a name the model does not have is a compile error at that field.

The filters and the page are flat parameters, but sort is a list of fields and orders, which a query string writes with brackets: ?username_sw=ad&sort[0][field]=username&sort[0][order]=ascending. With the serde flag, read it with serde_qs, which understands that notation; serde_urlencoded, which axum's own Query extractor uses, does not. A mirror using another serializer needs a reader of its own that handles a list of structs.

The persistence layer maps the model's fields onto the columns of its entity, and gets the SQL from that:

#[derive(sqlx::FromRow, Columns)]
#[columns(model = UserModel)]
pub struct User {
    pub id: i32,
    pub username: String,
}

#[derive(AppendConditions)]
#[append_conditions(columns = User)]
pub struct UsersFilterOptionsModelWrapper(pub UsersFilterOptionsModel);

#[derive(AppendToQuery)]
#[append_to_query(columns = User, filters = UsersFilterOptionsModelWrapper)]
pub struct UsersQueryModelWrapper(pub UsersQueryModel);

// In the repository: adds the WHERE, ORDER BY and LIMIT/OFFSET clauses.
let mut query = QueryBuilder::<Postgres>::new("SELECT * FROM users ");
// An optional hook to add conditions of your own (e.g. access rules); none here.
let guard: Option<fn(&mut QueryBuilder<Postgres>, &UsersQueryModelWrapper)> = None;
UsersQueryModelWrapper(filters).append_to_query(&mut query, guard);

Every value is bound, never interpolated, and a domain field that reaches SQL without a column fails the build.

Partial updates (PATCH with JSON merge patch semantics) work the same way. A patch says, for each field, whether it is left out, cleared or replaced. A field that can be cleared is a queryweave::Patch<T> (Missing, Null or Value(t)); one that cannot is an Option<T>. Option<Option<T>> is not supported, and the derives reject it with an error naming Patch<T>. MergePatch on the model merges a patch into it and reports which fields changed, Columns writes those fields as a SET clause, and ValidateNonNullable on the API's patch type rejects null for fields that cannot be cleared.

Merge patches are behind the merge-patch feature, on by default. Turn the default features off on the queryweave crates to use the filters alone (and keep queryweave-sql's sqlx feature: features = ["sqlx"]).

The crates

You depend on queryweave-derive for the macros, and on one runtime crate per layer, which holds the types the generated code uses:

Crate	Use it in	What it holds
`queryweave-derive`	every layer	The derive macros.
`queryweave`	the domain	The core: query, sort and patch data. No database or serializer dependency, so the domain stays free of both.
`queryweave-api`	the API layer	Pages and sort directions for API types, with optional `serde`, `utoipa` and `schemars` support.
`queryweave-sql`	the persistence layer	The SQL, written into sqlx's `QueryBuilder` (feature `sqlx`, default) or sea-query's / SeaORM's statements (feature `sea-query`), or as Diesel's typed expressions (feature `diesel`), for Postgres, MySQL/MariaDB, SQLite. No driver dependency.
`queryweave-codegen`	a proc-macro crate of yours	The code generation itself, for when you want your own naming rules or integrations (see below).

queryweave-api and queryweave-sql re-export the core, so each layer needs only its own runtime crate.

Integrations

A mirror only depends on the libraries it asks for. Without flags it depends on nothing but queryweave; each flag adds what that library needs:

Flag	What the mirror's types get
`serde`	Deserializable query parameters, and a page type for responses.
`utoipa`	OpenAPI documentation.
`validator`	Validation of the page size and sort (it reports errors through serde, so it needs `serde` too).
`schemars`	JSON schemas, as used by `aide`, `okapi` or `dropshot`.
`garde`	Validation of the page size and sort, without a serializer.

Each layer picks its own flags, so a gRPC layer mirroring the same model does not pull in the API layer's libraries. See docs/integrations.md.

Your own rules

The names queryweave generates follow conventions: UserModel gets UsersQueryModel, UserDto gets UsersQueryParams, a filter on username with sw is username_sw. If your project names things differently, or needs an integration queryweave does not ship (another serializer, GraphQL), you write a small proc-macro crate of your own on top of queryweave-codegen with your conventions. See docs/conventions.md.

Documentation

docs/guide.md: every derive, what you write and what you get.
docs/integrations.md: the integration flags, and writing your own.
docs/conventions.md: naming rules and runtime paths of your own.
docs/architecture.md: how it works inside, for contributors.
docs/ai/architecture-reference.md: a condensed reference for AI agents.

Development

queryweave is a Cargo workspace of its own. From its root, one script runs every check:

sh scripts/check.sh        # formatting, lints, unit and doc tests, rustdoc,
                           # every queryweave-api feature combination and the
                           # filters-only build; needs no Docker
sh scripts/check.sh ci     # the same, plus the database tests (Postgres,
                           # MySQL and MariaDB in containers: needs Docker)
sh scripts/check.sh all    # the same, plus the trybuild UI tests, which are slow
                           # (each case is a full cargo build)

The tests needing neither Docker nor a full build per case run with cargo nextest run --workspace --profile fast.

Pre-commit hook

pre-commit.sh runs scripts/check.sh fast before each commit. To install it as the repository's git hook, build pre_commit_script_builder (a small binary that runs the script) and copy it into .git/hooks:

cd pre_commit_script_builder && cargo build --release && cd ..
cp pre_commit_script_builder/target/release/pre-commit .git/hooks/pre-commit
# Windows: copy pre-commit.exe to .git\hooks\pre-commit.exe instead

Rebuilding is only needed when the builder changes: edits to pre-commit.sh or scripts/check.sh apply right away.

Status

queryweave is published on crates.io. Depend on queryweave-derive and on the runtime crate of each layer (see The crates):

[dependencies]

queryweave-derive = "0.2"

queryweave = "0.2" # or `queryweave-api` / `queryweave-sql`, per layer

Its version is 0.2.0: the API may still change before 1.0. What changed in each release, and how to upgrade, is in CHANGELOG.md.

Minimum supported Rust version

Rust 1.88, with every feature. SeaORM 2.0 itself needs Rust 1.94, so a project writing into SeaORM's queries (through the sea-query feature) needs that version for SeaORM's sake.

License

Licensed under either of Apache License, Version 2.0 or MIT license, at your option.

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in this crate by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.

queryweave-codegen 0.2.0