shard-crystal-sqlite3/src/sqlite3/connection.cr

137 lines
4.0 KiB
Crystal

class SQLite3::Connection < DB::Connection
record Options,
filename : String = ":memory:",
# pragmas
busy_timeout : String? = nil,
cache_size : String? = nil,
foreign_keys : String? = nil,
journal_mode : String? = nil,
synchronous : String? = nil,
wal_autocheckpoint : String? = nil do
def self.from_uri(uri : URI, default = Options.new)
params = HTTP::Params.parse(uri.query || "")
Options.new(
filename: URI.decode_www_form((uri.host || "") + uri.path),
# pragmas
busy_timeout: params.fetch("busy_timeout", default.busy_timeout),
cache_size: params.fetch("cache_size", default.cache_size),
foreign_keys: params.fetch("foreign_keys", default.foreign_keys),
journal_mode: params.fetch("journal_mode", default.journal_mode),
synchronous: params.fetch("synchronous", default.synchronous),
wal_autocheckpoint: params.fetch("wal_autocheckpoint", default.wal_autocheckpoint),
)
end
def pragma_statement
res = String.build do |str|
pragma_append(str, "busy_timeout", busy_timeout)
pragma_append(str, "cache_size", cache_size)
pragma_append(str, "foreign_keys", foreign_keys)
pragma_append(str, "journal_mode", journal_mode)
pragma_append(str, "synchronous", synchronous)
pragma_append(str, "wal_autocheckpoint", wal_autocheckpoint)
end
res.empty? ? nil : res
end
private def pragma_append(io, key, value)
return unless value
io << "PRAGMA #{key}=#{value};"
end
end
def initialize(options : ::DB::Connection::Options, sqlite3_options : Options)
super(options)
check LibSQLite3.open_v2(sqlite3_options.filename, out @db, (Flag::READWRITE | Flag::CREATE), nil)
# 2 means 2 arguments; 1 is the code for UTF-8
check LibSQLite3.create_function(@db, "regexp", 2, 1, nil, SQLite3::REGEXP_FN, nil, nil)
if pragma_statement = sqlite3_options.pragma_statement
check LibSQLite3.exec(@db, pragma_statement, nil, nil, nil)
end
rescue
raise DB::ConnectionRefused.new
end
def self.filename(uri : URI)
URI.decode_www_form((uri.host || "") + uri.path)
end
def build_prepared_statement(query) : Statement
Statement.new(self, query)
end
def build_unprepared_statement(query) : Statement
# sqlite3 does not support unprepared statement.
# All statements once prepared should be released
# when unneeded. Unprepared statement are not aim
# to leave state in the connection. Mimicking them
# with prepared statement would be wrong with
# respect connection resources.
raise DB::Error.new("SQLite3 driver does not support unprepared statements")
end
def do_close
super
check LibSQLite3.close(self)
end
# :nodoc:
def perform_begin_transaction
self.prepared.exec "BEGIN"
end
# :nodoc:
def perform_commit_transaction
self.prepared.exec "COMMIT"
end
# :nodoc:
def perform_rollback_transaction
self.prepared.exec "ROLLBACK"
end
# :nodoc:
def perform_create_savepoint(name)
self.prepared.exec "SAVEPOINT #{name}"
end
# :nodoc:
def perform_release_savepoint(name)
self.prepared.exec "RELEASE SAVEPOINT #{name}"
end
# :nodoc:
def perform_rollback_savepoint(name)
self.prepared.exec "ROLLBACK TO #{name}"
end
# Dump the database to another SQLite3 database. This can be used for backing up a SQLite3 Database
# to disk or the opposite
def dump(to : SQLite3::Connection)
backup_item = LibSQLite3.backup_init(to.@db, "main", @db, "main")
if backup_item.null?
raise Exception.new(to.@db)
end
code = LibSQLite3.backup_step(backup_item, -1)
if code != LibSQLite3::Code::DONE
raise Exception.new(to.@db)
end
code = LibSQLite3.backup_finish(backup_item)
if code != LibSQLite3::Code::OKAY
raise Exception.new(to.@db)
end
end
def to_unsafe
@db
end
private def check(code)
raise Exception.new(self) unless code == 0
end
end