Struct migrant_lib::migration::FnMigration

pub struct FnMigration<T, U> {
    pub tag: String,
    pub up: Option<T>,
    pub down: Option<U>,
}

Define a programmable migration

FnMigrations are provided a ConnConfig instance and given free rein to do as they please. Database specific features (d-postgres/d-sqlite/d-mysql) are required to use this functionality.

Note, both an up and down function must be provided. There is a noop function available (migrant_lib::migration::noop) for convenience.

Example

fn add_data(config: ConnConfig) -> Result<(), Box<std::error::Error>> {
    // do stuff...
    Ok(())
}

FnMigration::with_tag("add-user-data")
    .up(add_data)
    .down(migrant_lib::migration::noop);

Fields

tag: String

up: Option<T>

down: Option<U>

Methods

impl<T, U> FnMigration<T, U> where     T: 'static + Clone + Fn(ConnConfig) -> Result<(), Box<dyn Error>>,     U: 'static + Clone + Fn(ConnConfig) -> Result<(), Box<dyn Error>>,

pub fn with_tag(_tag: &str) -> DatabaseFeatureRequired

Create a new FnMigration with the given tag

pub fn up(&mut self, f_up: T) -> &mut Self

Function to use for up migrations

Function must have the signature fn(ConnConfig) -> std::result::Result<(), Box<std::error::Error>>.

pub fn down(&mut self, f_down: U) -> &mut Self

Function to use for down migrations

Function must have the signature fn(ConnConfig) -> std::result::Result<(), Box<std::error::Error>>.

pub fn boxed(&self) -> Box<dyn Migratable>

Box this migration up so it can be stored with other migrations

Trait Implementations

impl<T, U> Migratable for FnMigration<T, U> where     T: 'static + Clone + Fn(ConnConfig) -> Result<(), Box<dyn Error>>,     U: 'static + Clone + Fn(ConnConfig) -> Result<(), Box<dyn Error>>,

fn apply_up(&self, _: DbKind, config: &Config) -> Result<(), Box<dyn Error>>

Define functionality that runs for up migrations

fn apply_down(&self, _: DbKind, config: &Config) -> Result<(), Box<dyn Error>>

Define functionality that runs for down migrations

fn tag(&self) -> String

A unique identifying tag

fn description(&self, _: &Direction) -> String

Option migration description. Defaults to Migratable::tag

impl<T: Clone, U: Clone> Clone for FnMigration<T, U>

fn clone(&self) -> FnMigration<T, U>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<T: Debug, U: Debug> Debug for FnMigration<T, U>

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.