openethereum/parity/migration.rs
2016-10-01 14:33:19 +02:00

334 lines
12 KiB
Rust

// Copyright 2015, 2016 Ethcore (UK) Ltd.
// This file is part of Parity.
// Parity is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// Parity is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with Parity. If not, see <http://www.gnu.org/licenses/>.
use std::fs;
use std::fs::File;
use std::io::{Read, Write, Error as IoError, ErrorKind};
use std::path::{Path, PathBuf};
use std::fmt::{Display, Formatter, Error as FmtError};
use std::sync::Arc;
use util::journaldb::Algorithm;
use util::migration::{Manager as MigrationManager, Config as MigrationConfig, Error as MigrationError, Migration};
use util::kvdb::{CompactionProfile, Database, DatabaseConfig};
use ethcore::migrations;
use ethcore::db;
use ethcore::migrations::Extract;
/// Database is assumed to be at default version, when no version file is found.
const DEFAULT_VERSION: u32 = 5;
/// Current version of database models.
const CURRENT_VERSION: u32 = 9;
/// First version of the consolidated database.
const CONSOLIDATION_VERSION: u32 = 9;
/// Defines how many items are migrated to the new version of database at once.
const BATCH_SIZE: usize = 1024;
/// Version file name.
const VERSION_FILE_NAME: &'static str = "db_version";
/// Migration related erorrs.
#[derive(Debug)]
pub enum Error {
/// Returned when current version cannot be read or guessed.
UnknownDatabaseVersion,
/// Migration does not support existing pruning algorithm.
UnsupportedPruningMethod,
/// Existing DB is newer than the known one.
FutureDBVersion,
/// Migration is not possible.
MigrationImpossible,
/// Migration unexpectadly failed.
MigrationFailed,
/// Internal migration error.
Internal(MigrationError),
/// Migration was completed succesfully,
/// but there was a problem with io.
Io(IoError),
}
impl Display for Error {
fn fmt(&self, f: &mut Formatter) -> Result<(), FmtError> {
let out = match *self {
Error::UnknownDatabaseVersion => "Current database version cannot be read".into(),
Error::UnsupportedPruningMethod => "Unsupported pruning method for database migration. Delete DB and resync.".into(),
Error::FutureDBVersion => "Database was created with newer client version. Upgrade your client or delete DB and resync.".into(),
Error::MigrationImpossible => format!("Database migration to version {} is not possible.", CURRENT_VERSION),
Error::MigrationFailed => "Database migration unexpectedly failed".into(),
Error::Internal(ref err) => format!("{}", err),
Error::Io(ref err) => format!("Unexpected io error on DB migration: {}.", err),
};
write!(f, "{}", out)
}
}
impl From<IoError> for Error {
fn from(err: IoError) -> Self {
Error::Io(err)
}
}
impl From<MigrationError> for Error {
fn from(err: MigrationError) -> Self {
match err {
MigrationError::Io(e) => Error::Io(e),
_ => Error::Internal(err),
}
}
}
/// Returns the version file path.
fn version_file_path(path: &Path) -> PathBuf {
let mut file_path = path.to_owned();
file_path.push(VERSION_FILE_NAME);
file_path
}
/// Reads current database version from the file at given path.
/// If the file does not exist returns `DEFAULT_VERSION`.
fn current_version(path: &Path) -> Result<u32, Error> {
match File::open(version_file_path(path)) {
Err(ref err) if err.kind() == ErrorKind::NotFound => Ok(DEFAULT_VERSION),
Err(_) => Err(Error::UnknownDatabaseVersion),
Ok(mut file) => {
let mut s = String::new();
try!(file.read_to_string(&mut s).map_err(|_| Error::UnknownDatabaseVersion));
u32::from_str_radix(&s, 10).map_err(|_| Error::UnknownDatabaseVersion)
},
}
}
/// Writes current database version to the file.
/// Creates a new file if the version file does not exist yet.
fn update_version(path: &Path) -> Result<(), Error> {
try!(fs::create_dir_all(path));
let mut file = try!(File::create(version_file_path(path)));
try!(file.write_all(format!("{}", CURRENT_VERSION).as_bytes()));
Ok(())
}
/// Consolidated database path
fn consolidated_database_path(path: &Path) -> PathBuf {
let mut state_path = path.to_owned();
state_path.push("db");
state_path
}
/// Database backup
fn backup_database_path(path: &Path) -> PathBuf {
let mut backup_path = path.to_owned();
backup_path.pop();
backup_path.push("temp_backup");
backup_path
}
/// Default migration settings.
pub fn default_migration_settings(compaction_profile: &CompactionProfile) -> MigrationConfig {
MigrationConfig {
batch_size: BATCH_SIZE,
compaction_profile: *compaction_profile,
}
}
/// Migrations on the consolidated database.
fn consolidated_database_migrations(compaction_profile: &CompactionProfile) -> Result<MigrationManager, Error> {
let manager = MigrationManager::new(default_migration_settings(compaction_profile));
Ok(manager)
}
/// Consolidates legacy databases into single one.
fn consolidate_database(
old_db_path: PathBuf,
new_db_path: PathBuf,
column: Option<u32>,
extract: Extract,
compaction_profile: &CompactionProfile) -> Result<(), Error> {
fn db_error(e: String) -> Error {
warn!("Cannot open Database for consolidation: {:?}", e);
Error::MigrationFailed
}
let mut migration = migrations::ToV9::new(column, extract);
let config = default_migration_settings(compaction_profile);
let mut db_config = DatabaseConfig {
max_open_files: 64,
cache_sizes: Default::default(),
compaction: config.compaction_profile,
columns: None,
wal: true,
};
let old_path_str = try!(old_db_path.to_str().ok_or(Error::MigrationImpossible));
let new_path_str = try!(new_db_path.to_str().ok_or(Error::MigrationImpossible));
let cur_db = Arc::new(try!(Database::open(&db_config, old_path_str).map_err(db_error)));
// open new DB with proper number of columns
db_config.columns = migration.columns();
let mut new_db = try!(Database::open(&db_config, new_path_str).map_err(db_error));
// Migrate to new database (default column only)
try!(migration.migrate(cur_db, &config, &mut new_db, None));
Ok(())
}
/// Migrates database at given position with given migration rules.
fn migrate_database(version: u32, db_path: PathBuf, mut migrations: MigrationManager) -> Result<(), Error> {
// check if migration is needed
if !migrations.is_needed(version) {
return Ok(())
}
let backup_path = backup_database_path(&db_path);
// remove the backup dir if it exists
let _ = fs::remove_dir_all(&backup_path);
// migrate old database to the new one
let temp_path = try!(migrations.execute(&db_path, version));
// create backup
try!(fs::rename(&db_path, &backup_path));
// replace the old database with the new one
if let Err(err) = fs::rename(&temp_path, &db_path) {
// if something went wrong, bring back backup
try!(fs::rename(&backup_path, &db_path));
return Err(err.into());
}
// remove backup
try!(fs::remove_dir_all(&backup_path));
Ok(())
}
fn exists(path: &Path) -> bool {
fs::metadata(path).is_ok()
}
/// Migrates the database.
pub fn migrate(path: &Path, pruning: Algorithm, compaction_profile: CompactionProfile) -> Result<(), Error> {
// read version file.
let version = try!(current_version(path));
// migrate the databases.
// main db directory may already exists, so let's check if we have blocks dir
if version > CURRENT_VERSION {
return Err(Error::FutureDBVersion);
}
// We are in the latest version, yay!
if version == CURRENT_VERSION {
return Ok(())
}
// Perform pre-consolidation migrations
if version < CONSOLIDATION_VERSION && exists(&legacy::blocks_database_path(path)) {
println!("Migrating database from version {} to {}", version, CONSOLIDATION_VERSION);
try!(migrate_database(version, legacy::blocks_database_path(path), try!(legacy::blocks_database_migrations(&compaction_profile))));
try!(migrate_database(version, legacy::extras_database_path(path), try!(legacy::extras_database_migrations(&compaction_profile))));
try!(migrate_database(version, legacy::state_database_path(path), try!(legacy::state_database_migrations(pruning, &compaction_profile))));
let db_path = consolidated_database_path(path);
// Remove the database dir (it shouldn't exist anyway, but it might when migration was interrupted)
let _ = fs::remove_dir_all(db_path.clone());
try!(consolidate_database(legacy::blocks_database_path(path), db_path.clone(), db::COL_HEADERS, Extract::Header, &compaction_profile));
try!(consolidate_database(legacy::blocks_database_path(path), db_path.clone(), db::COL_BODIES, Extract::Body, &compaction_profile));
try!(consolidate_database(legacy::extras_database_path(path), db_path.clone(), db::COL_EXTRA, Extract::All, &compaction_profile));
try!(consolidate_database(legacy::state_database_path(path), db_path.clone(), db::COL_STATE, Extract::All, &compaction_profile));
try!(consolidate_database(legacy::trace_database_path(path), db_path.clone(), db::COL_TRACE, Extract::All, &compaction_profile));
let _ = fs::remove_dir_all(legacy::blocks_database_path(path));
let _ = fs::remove_dir_all(legacy::extras_database_path(path));
let _ = fs::remove_dir_all(legacy::state_database_path(path));
let _ = fs::remove_dir_all(legacy::trace_database_path(path));
println!("Migration finished");
}
// Further migrations
if version >= CONSOLIDATION_VERSION && version < CURRENT_VERSION && exists(&consolidated_database_path(path)) {
println!("Migrating database from version {} to {}", ::std::cmp::max(CONSOLIDATION_VERSION, version), CURRENT_VERSION);
try!(migrate_database(version, consolidated_database_path(path), try!(consolidated_database_migrations(&compaction_profile))));
println!("Migration finished");
}
// update version file.
update_version(path)
}
/// Old migrations utilities
mod legacy {
use super::*;
use std::path::{Path, PathBuf};
use util::journaldb::Algorithm;
use util::migration::{Manager as MigrationManager};
use util::kvdb::CompactionProfile;
use ethcore::migrations;
/// Blocks database path.
pub fn blocks_database_path(path: &Path) -> PathBuf {
let mut blocks_path = path.to_owned();
blocks_path.push("blocks");
blocks_path
}
/// Extras database path.
pub fn extras_database_path(path: &Path) -> PathBuf {
let mut extras_path = path.to_owned();
extras_path.push("extras");
extras_path
}
/// State database path.
pub fn state_database_path(path: &Path) -> PathBuf {
let mut state_path = path.to_owned();
state_path.push("state");
state_path
}
/// Trace database path.
pub fn trace_database_path(path: &Path) -> PathBuf {
let mut blocks_path = path.to_owned();
blocks_path.push("tracedb");
blocks_path
}
/// Migrations on the blocks database.
pub fn blocks_database_migrations(compaction_profile: &CompactionProfile) -> Result<MigrationManager, Error> {
let mut manager = MigrationManager::new(default_migration_settings(compaction_profile));
try!(manager.add_migration(migrations::blocks::V8::default()).map_err(|_| Error::MigrationImpossible));
Ok(manager)
}
/// Migrations on the extras database.
pub fn extras_database_migrations(compaction_profile: &CompactionProfile) -> Result<MigrationManager, Error> {
let mut manager = MigrationManager::new(default_migration_settings(compaction_profile));
try!(manager.add_migration(migrations::extras::ToV6).map_err(|_| Error::MigrationImpossible));
Ok(manager)
}
/// Migrations on the state database.
pub fn state_database_migrations(pruning: Algorithm, compaction_profile: &CompactionProfile) -> Result<MigrationManager, Error> {
let mut manager = MigrationManager::new(default_migration_settings(compaction_profile));
let res = match pruning {
Algorithm::Archive => manager.add_migration(migrations::state::ArchiveV7::default()),
Algorithm::OverlayRecent => manager.add_migration(migrations::state::OverlayRecentV7::default()),
_ => return Err(Error::UnsupportedPruningMethod),
};
try!(res.map_err(|_| Error::MigrationImpossible));
Ok(manager)
}
}