Extensions

Extensions are optional packages that add cross-cutting behavior or higher-level data structures without making Oro core larger.

db, err := oro.Open(oro.Config{
    Connections: map[string]oro.ConnectionConfig{
        "default": {Driver: sqlite.Open("app.db")},
    },
    Extensions: []oro.Extension{
        tenant.Extension(tenant.Fields("TenantID")),
        nestedset.Extension(),
    },
})

What extensions can do

An extension can hook into specific lifecycle points:

Query-chain Apply

Query-chain extensions compose through db.Use[T]().Apply(...). Extension packages provide behavior objects, while Where, With, OrderBy, pagination, aggregation, and other query methods still come from the core ModelQuery.

products, err := db.Use[Product]().
    Apply(translation.Locale("zh-CN")).
    Where("Status", "online").
    OrderByDesc("ID").
    Get(ctx)

children, err := db.Use[Category]().
    Apply(nestedset.DescendantsOf(root), nestedset.DefaultOrder()).
    Where("Status", "enabled").
    Get(ctx)

Structural business services remain in extension packages. For example, tree-aware create, move, and delete operations use nestedset.Use[Category](db) because they are not simple query filters.

Embedded extension fields

Some extensions need model fields. Oro supports this through marked embedded field structs:

type Category struct {
    oro.Model
    nestedset.NodeFields

    Name string
}

nestedset.NodeFields implements Oro’s embedded-field marker, so the schema parser treats its exported fields as normal model fields. This keeps extension fields reusable without struct tags or code generation.

First-party extensions