Frequently Asked Questions

General

What is CRUDCrate?

CRUDCrate is a Rust library that generates complete REST APIs from Sea-ORM entities using derive macros. It eliminates boilerplate code for CRUD operations, filtering, sorting, pagination, and relationships.

How does it compare to other solutions?

What security features are included?

CRUDCrate includes:

• SQL injection prevention
• Pagination DoS protection
• Comprehensive error handling
• Proper logging integration

Installation

What are the minimum Rust version requirements?

Rust 1.70+ is required for stable proc-macro features.

Do I need to install Sea-ORM separately?

Yes. CRUDCrate works alongside Sea-ORM:

[dependencies]
crudcrate = "0.15"
sea-orm = { version = "2.0", features = ["runtime-tokio-rustls", "sqlx-postgres"] }

Usage

Can I use CRUDCrate with an existing Sea-ORM project?

Yes! Just add #[derive(EntityToModels)] and #[crudcrate(...)] attributes to your existing entities.

How do I customize the generated endpoints?

Three ways:

1. Attributes: Configure behavior with #[crudcrate(...)]
2. CRUDOperations: Implement hooks for business logic
3. Custom Handlers: Replace entire handlers when needed

Can I have some entities without routers?

Yes. Only add generate_router when you want endpoints:

// With router
#[crudcrate(generate_router)]

// Without router (just models)
#[crudcrate()]

How do I add authentication?

Use Axum middleware:

let app = Router::new()
    .merge(protected_router())
    .layer(middleware::from_fn(auth_middleware));

See Security for details.

Can I have different auth for different routes?

Yes. Use nested routers:

let public = Router::new().merge(public_routes());

let protected = Router::new()
    .merge(admin_routes())
    .layer(admin_auth_layer);

let app = Router::new().merge(public).merge(protected);

Filtering & Search

Which fields can be filtered?

Only fields marked #[crudcrate(filterable)]:

#[crudcrate(filterable)]  // Can filter
pub status: String,

pub secret: String,  // Cannot filter

How does fulltext search work?

Fields marked #[crudcrate(fulltext)] are searched with ?q=:

GET /items?q=search terms

The query uses database-optimized search (GIN for Postgres, FULLTEXT for MySQL).

Can I combine filters and search?

Yes:

GET /items?filter={"status":"active"}&q=urgent&sort=["created_at","DESC"]

Relationships

How do I load related entities?

1. Define Sea-ORM relations
2. Add join field with #[crudcrate(non_db_attr, join(one))]

#[sea_orm(ignore)]
#[crudcrate(non_db_attr, join(one))]
pub comments: Vec<Comment>,

Why are relationships not loading?

Check that:

1. #[sea_orm(ignore)] is present
2. #[crudcrate(non_db_attr)] is present
3. Sea-ORM Related trait is implemented
4. join(...) specifies one and/or all

How do I prevent circular references?

Use depth limit:

#[crudcrate(non_db_attr, join(one, depth = 2))]

Performance

Is CRUDCrate slow?

No. Generated code has zero runtime overhead. All generation happens at compile time.

How do I optimize for large tables?

1. Add database indexes on filtered/sorted fields
2. Use pagination (built-in limits: 1000 items max)
3. Exclude heavy fields from lists: #[crudcrate(exclude(list))]
4. Limit join depth

Does loading relationships cause N+1 queries?

No: get_all() with join(all) uses batch loading that reduces N+1 queries to just 2 queries (1 for parents + 1 per join field) using WHERE parent_id IN (...). This applies to depth=1 joins; deeper joins (depth > 1) may issue additional queries for nested relations. Single-item get_one() uses per-item queries, which is acceptable for individual lookups.

Troubleshooting

Compilation error: “cannot find derive macro”

Import it:

use crudcrate::EntityToModels;

Error: “field not found” when filtering

The field must be marked filterable:

#[crudcrate(filterable)]
pub status: String,

Relationships return empty

Ensure:

1. Database has related records
2. Sea-ORM Related trait is implemented
3. Join is configured: join(one) or join(one, all)

“Too many items” error on bulk delete

Built-in safety limit is 100 items. Split into multiple requests.

Timestamp fields not auto-updating

Check:

1. on_create and on_update are set
2. Field is excluded from update model: exclude(update)

#[crudcrate(exclude(create, update), on_create = chrono::Utc::now(), on_update = chrono::Utc::now())]
pub updated_at: DateTimeUtc,

Migration

Can I migrate from manual handlers?

Yes. CRUDCrate is additive. You can:

1. Start with one entity
2. Keep existing handlers for others
3. Gradually migrate

How do I migrate to a new version?

Check the Changelog for breaking changes. Most updates are backward compatible.

Contributing

How can I contribute?

See the Contributing section of the README.

Where do I report bugs?

Open an issue on GitHub.

Is there a roadmap?

Planned features:

• GraphQL support
• OpenAPI generation
• More database optimizations
• Cursor-based pagination option

Learn More

• Getting Started: First Steps Tutorial
• Examples: Minimal Example
• Reference: Field Attributes