Struct History 

pub struct History { /* private fields */ }

A TOML-serializable record of all migrations that have been generated.

The history file lives at <migration_path>/history.toml and is the source of truth for which migrations exist and what order they were created in. Each entry is a HistoryEntry.

The file carries a version number. History::load and the FromStr implementation reject files whose version does not match the current format.

Examples

use toasty_core::migration::{History, HistoryEntry};

let mut history = History::new();
assert_eq!(history.next_migration_number(), 0);

history.add_entry(HistoryEntry {
    id: 100,
    name: "0000_init.sql".to_string(),
    snapshot_name: "0000_snapshot.toml".to_string(),
    checksum: None,
});
assert_eq!(history.next_migration_number(), 1);
assert_eq!(history.entries().len(), 1);

// Round-trip through TOML serialization
let serialized = history.to_string();
let restored: History = serialized.parse().unwrap();
assert_eq!(restored.entries()[0].id, 100);

Implementations

impl History

pub fn new() -> Self

Create a new empty history.

pub fn load(path: impl AsRef<Path>) -> Result<Self>

Load history from a TOML file.

pub fn save(&self, path: impl AsRef<Path>) -> Result<()>

Save the history to a TOML file.

pub fn load_or_default(path: impl AsRef<Path>) -> Result<Self>

Loads the history file, or returns an empty one if it does not exist.

pub fn entries(&self) -> &[HistoryEntry]

Returns the ordered list of entries in this history.

Entries appear in the order they were added. An empty slice means no migrations have been recorded yet.

Examples

use toasty_core::migration::{History, HistoryEntry};

let mut history = History::new();
assert!(history.entries().is_empty());

history.add_entry(HistoryEntry {
    id: 1,
    name: "0001_init.sql".to_string(),
    snapshot_name: "0001_snapshot.toml".to_string(),
    checksum: None,
});
assert_eq!(history.entries().len(), 1);
assert_eq!(history.entries()[0].name, "0001_init.sql");

pub fn next_migration_number(&self) -> u32

Get the next migration number by parsing the last entry’s name.

pub fn add_entry(&mut self, entry: HistoryEntry)

Add an entry to the history.

pub fn remove_entry(&mut self, index: usize)

Remove an entry from the history by index.

Trait Implementations

impl Clone for History

fn clone(&self) -> History

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for History

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

Formats the value using the given formatter.

impl Default for History

fn default() -> Self

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for History

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Display for History

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

Formats the value using the given formatter.

impl FromStr for History

type Err = Error

The associated error which can be returned from parsing.

fn from_str(s: &str) -> Result<Self>

Parses a string s to return a value of this type.

impl Serialize for History

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.