toasty_core/
schema.rs

1//! Schema representation for Toasty, split into three layers.
2//!
3//! - [`app`] -- Model-level definitions: fields, relations, constraints. This
4//!   is what the generated Rust code sees.
5//! - [`db`] -- Table/column-level definitions. This is what the database sees.
6//! - [`mapping`] -- Connects app fields to database columns, supporting
7//!   non-1:1 mappings such as embedded structs and enums.
8//!
9//! The top-level [`Schema`] struct ties all three layers together and is
10//! constructed via [`Builder`].
11//!
12//! # Examples
13//!
14//! ```ignore
15//! use toasty_core::schema::{Schema, Builder};
16//!
17//! let schema = Builder::new()
18//!     .build(app_schema, &driver_capability)
19//!     .expect("schema should be valid");
20//!
21//! // Look up the database table backing a model
22//! let table = schema.table_for(model_id);
23//! ```
24
25/// Application-level (model-oriented) schema definitions.
26pub mod app;
27
28mod builder;
29pub use builder::Builder;
30
31/// Database-level (table/column-oriented) schema definitions.
32pub mod db;
33
34/// Schema-diff types: compare two schema versions and produce structural changes.
35pub mod diff;
36
37/// Mapping between the app layer and the database layer.
38pub mod mapping;
39use mapping::Mapping;
40
41mod name;
42pub use name::Name;
43
44mod verify;
45
46use crate::Result;
47use app::ModelId;
48use db::{Table, TableId};
49
50/// The combined schema: app-level models, database-level tables, and the
51/// mapping that connects them.
52///
53/// Constructed with [`Builder`] and validated on creation. Immutable at runtime.
54///
55/// # Examples
56///
57/// ```ignore
58/// use toasty_core::Schema;
59///
60/// fn inspect(schema: &Schema) {
61///     for (id, model) in &schema.app.models {
62///         let table = schema.table_for(*id);
63///         println!("{} -> {}", model.name().snake_case(), table.name);
64///     }
65/// }
66/// ```
67#[derive(Debug)]
68pub struct Schema {
69    /// Application-level schema.
70    pub app: app::Schema,
71
72    /// Database-level schema.
73    pub db: db::Schema,
74
75    /// Maps the app-level schema to the db-level schema.
76    pub mapping: Mapping,
77}
78
79impl Schema {
80    /// Returns a new [`Builder`] for constructing a `Schema`.
81    ///
82    /// # Examples
83    ///
84    /// ```ignore
85    /// use toasty_core::Schema;
86    ///
87    /// let builder = Schema::builder();
88    /// ```
89    pub fn builder() -> Builder {
90        Builder::default()
91    }
92
93    /// Returns the mapping for the given model.
94    ///
95    /// # Panics
96    ///
97    /// Panics if `id` does not correspond to a model in the schema.
98    ///
99    /// # Examples
100    ///
101    /// ```ignore
102    /// use toasty_core::Schema;
103    ///
104    /// let mapping = schema.mapping_for(model_id);
105    /// println!("table: {:?}", mapping.table);
106    /// ```
107    pub fn mapping_for(&self, id: impl Into<ModelId>) -> &mapping::Model {
108        self.mapping.model(id)
109    }
110
111    /// Returns the database table that stores the given model.
112    ///
113    /// # Panics
114    ///
115    /// Panics if `id` does not correspond to a model in the schema.
116    ///
117    /// # Examples
118    ///
119    /// ```ignore
120    /// let table = schema.table_for(model_id);
121    /// println!("table name: {}", table.name);
122    /// ```
123    pub fn table_for(&self, id: impl Into<ModelId>) -> &Table {
124        self.db.table(self.table_id_for(id))
125    }
126
127    /// Returns the [`TableId`] for the table that stores the given model.
128    ///
129    /// # Panics
130    ///
131    /// Panics if `id` does not correspond to a model in the schema.
132    pub fn table_id_for(&self, id: impl Into<ModelId>) -> TableId {
133        self.mapping.model(id).table
134    }
135}
toasty_core/schema.rs

toasty_core/
schema.rs
