Struct diesel_migrations::FileBasedMigrations

pub struct FileBasedMigrations { /* private fields */ }

A migration source based on a migration directory in the file system

A valid migration directroy contains a sub folder per migration. Each migration folder contains a up.sql file containing the migration itself and a down.sql file containing the nessesary SQL to revert the migration. Additionaly each folder can contain a metadata.toml file controling how the individual migration should be handled by the migration harness.

To embed an existing migration folder into the final binary see embed_migrations!.

Example

# Directory Structure
- 20151219180527_create_users
    - up.sql
    - down.sql
- 20160107082941_create_posts
    - up.sql
    - down.sql

-- 20151219180527_create_users/up.sql
CREATE TABLE users (
  id SERIAL PRIMARY KEY,
  name VARCHAR NOT NULL,
  hair_color VARCHAR
);

-- 20151219180527_create_users/down.sql
DROP TABLE users;

-- 20160107082941_create_posts/up.sql
CREATE TABLE posts (
  id SERIAL PRIMARY KEY,
  user_id INTEGER NOT NULL,
  title VARCHAR NOT NULL,
  body TEXT
);

-- 20160107082941_create_posts/down.sql
DROP TABLE posts;

# 20160107082941_create_posts/metadata.toml

# specifices if a migration is executed inside a
# transaction or not. This configuration is optional
# by default all migrations are run in transactions.
#
# For certain types of migrations, like creating an
# index onto a existing column, it is required
# to set this to false
run_in_transaction = true

Implementations

impl FileBasedMigrations

pub fn from_path(path: impl AsRef<Path>) -> Result<Self, MigrationError>

Create a new file based migration source based on a specific path

This methods fails if the path passed as argument is no valid migration directory

pub fn find_migrations_directory() -> Result<Self, MigrationError>

Create a new file based migration source by searching the migration diretcory

This method looks in the current and all parent directories for a folder named migrations

This method fails if no valid migration directory is found

pub fn find_migrations_directory_in_path( path: impl AsRef<Path> ) -> Result<Self, MigrationError>

Create a new file based migration source by searching a give path for the migration directory

This method looks in the passed directory and all parent directories for a folder named migrations

This method fails if no valid migration directory is found

Trait Implementations

impl Clone for FileBasedMigrations

fn clone(&self) -> FileBasedMigrations

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<DB: Backend> MigrationSource<DB> for FileBasedMigrations

fn migrations(&self) -> Result<Vec<Box<dyn Migration<DB>>>>

Get a list of migrations associated with this migration soucre.