nim-rocksdb/rocksdb/transactiondb.nim

120 lines
3.7 KiB
Nim

# Nim-RocksDB
# Copyright 2024 Status Research & Development GmbH
# Licensed under either of
#
# * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or http://www.apache.org/licenses/LICENSE-2.0)
# * GPL license, version 2.0, ([LICENSE-GPLv2](LICENSE-GPLv2) or https://www.gnu.org/licenses/old-licenses/gpl-2.0.en.html)
#
# at your option. This file may not be copied, modified, or distributed except according to those terms.
## A `TransactionDbRef` can be used to open a connection to the RocksDB database
## with support for transactional operations against multiple column families.
## To create a new transaction call `beginTransaction` which will return a
## `TransactionRef`. To commit or rollback the transaction call `commit` or
## `rollback` on the `TransactionRef` type after applying changes to the transaction.
{.push raises: [].}
import
std/[sequtils, locks],
./lib/librocksdb,
./options/[dbopts, readopts, writeopts],
./transactions/[transaction, txdbopts, txopts],
./columnfamily/[cfopts, cfdescriptor, cfhandle],
./internal/[cftable, utils],
./rocksresult
export
dbopts,
txdbopts,
cfdescriptor,
readopts,
writeopts,
txopts,
transaction,
rocksresult
type
TransactionDbPtr* = ptr rocksdb_transactiondb_t
TransactionDbRef* = ref object
lock: Lock
cPtr: TransactionDbPtr
path: string
dbOpts: DbOptionsRef
txDbOpts: TransactionDbOptionsRef
cfTable: ColFamilyTableRef
proc openTransactionDb*(
path: string,
dbOpts = defaultDbOptions(),
txDbOpts = defaultTransactionDbOptions(),
columnFamilies: openArray[ColFamilyDescriptor] = []): RocksDBResult[TransactionDbRef] =
## Open a `TransactionDbRef` with the given options and column families.
## If no column families are provided the default column family will be used.
## If no options are provided the default options will be used.
var cfs = columnFamilies.toSeq()
if DEFAULT_COLUMN_FAMILY_NAME notin columnFamilies.mapIt(it.name()):
cfs.add(defaultColFamilyDescriptor())
var
cfNames = cfs.mapIt(it.name().cstring)
cfOpts = cfs.mapIt(it.options.cPtr)
cfHandles = newSeq[ColFamilyHandlePtr](cfs.len)
errors: cstring
let txDbPtr = rocksdb_transactiondb_open_column_families(
dbOpts.cPtr,
txDbOpts.cPtr,
path.cstring,
cfNames.len().cint,
cast[cstringArray](cfNames[0].addr),
cfOpts[0].addr,
cfHandles[0].addr,
cast[cstringArray](errors.addr))
bailOnErrors(errors)
let db = TransactionDbRef(
lock: createLock(),
cPtr: txDbPtr,
path: path,
dbOpts: dbOpts,
txDbOpts: txDbOpts,
cfTable: newColFamilyTable(cfNames.mapIt($it), cfHandles))
ok(db)
proc isClosed*(db: TransactionDbRef): bool {.inline.} =
## Returns `true` if the `TransactionDbRef` has been closed.
db.cPtr.isNil()
proc beginTransaction*(
db: TransactionDbRef,
readOpts = defaultReadOptions(),
writeOpts = defaultWriteOptions(),
txOpts = defaultTransactionOptions(),
columnFamily = DEFAULT_COLUMN_FAMILY_NAME): TransactionRef =
## Begin a new transaction against the database. The transaction will default
## to using the specified column family. If no column family is specified
## then the default column family will be used.
doAssert not db.isClosed()
let txPtr = rocksdb_transaction_begin(
db.cPtr,
writeOpts.cPtr,
txOpts.cPtr,
nil)
newTransaction(txPtr, readOpts, writeOpts, txOpts, columnFamily, db.cfTable)
proc close*(db: TransactionDbRef) =
## Close the `TransactionDbRef`.
withLock(db.lock):
if not db.isClosed():
db.dbOpts.close()
db.txDbOpts.close()
db.cfTable.close()
rocksdb_transactiondb_close(db.cPtr)
db.cPtr = nil