Trait Migration

pub trait Migration {
    const APP_NAME: &'static str;
    const MIGRATION_NAME: &'static str;
    const DEPENDENCIES: &'static [MigrationDependency];
    const OPERATIONS: &'static [Operation];
}

Available on crate feature db only.

A trait for defining a migration.

Cot CLI Usage

Typically, you shouldn’t need to use this directly. Instead, in most cases, this can be automatically generated by the Cot CLI.

Examples

use cot::db::migrations::{Field, Migration, MigrationDependency, Operation};
use cot::db::{DatabaseField, Identifier};

struct MyMigration;

impl Migration for MyMigration {
    const APP_NAME: &'static str = "myapp";
    const MIGRATION_NAME: &'static str = "m_0001_initial";
    const DEPENDENCIES: &'static [MigrationDependency] = &[];
    const OPERATIONS: &'static [Operation] = &[Operation::create_model()
        .table_name(Identifier::new("todoapp__my_model"))
        .fields(&[
            Field::new(Identifier::new("id"), <i32 as DatabaseField>::TYPE).primary_key(),
        ])
        .build()];
}

Required Associated Constants

const APP_NAME: &'static str

The name of the app that this migration belongs to.

const MIGRATION_NAME: &'static str

The name of the migration.

const DEPENDENCIES: &'static [MigrationDependency]

The list of dependencies of the migration.

const OPERATIONS: &'static [Operation]

The list of operations to apply in the migration.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementors