Perinci::Tx::Manager - Transaction manager
version 0.25
# used by Perinci::Access::InProcess
This class implements transaction and undo manager (TM), as specified by Rinci::function::Transaction and Riap::Transaction. It is meant to be instantiated by Perinci::Access::InProcess, but will also be passed to transactional functions to save undo/redo data.
It uses SQLite database to store transaction list and undo/redo data as well as transaction data directory to provide trash_dir/tmp_dir for functions that require it.
This is just a convenience so that methods that require tx_id will get the default value from here if tx_id not specified in arguments.
Nest level (by default 1, the outermost, increases by one for each increased nest level). A transactional function can call another transactional function, and that constitutes a nesting.
Internally, subcalls are also recorded in the call table, and its undo/redo steps in the undo_step/redo_step table. However, during rollback/undo/redo, the transaction manager only directly processes outermost calls (those with nest_level=1). The function's is responsible for using the subcall (and its steps) information.
call
undo_step
redo_step
Create new object. Arguments:
pa => OBJ
Perinci::Access::InProcess object. This is required by Perinci::Tx::Manager to load/get functions when it wants to perform undo/redo/recovery. Perinci::Access::InProcess conveniently require() the Perl modules and wraps the functions.
data_dir => STR (default ~/.perinci/.tx)
~/.perinci/.tx
max_txs => INT (default 1000)
Limit maximum number of transactions maintained by the TM, including all rolled back and committed transactions, since they are still recorded in the database. The default is 1000.
Not yet implemented.
After this limit is reached, cleanup will be performed to delete rolled back transactions, and after that committed transactions.
max_open_txs => INT (default 100)
Limit maximum number of open (in progress, aborted, prepared) transactions. This exclude resolved transactions (rolled back and committed). The default is no limit.
After this limit is reached, starting a new transaction will fail.
max_committed_txs => INT (default 100)
Limit maximum number of committed transactions that is recorded by the database. This is equal to the number of undo steps that are remembered.
After this limit is reached, cleanup will automatically be performed so that the oldest committed transactions are purged.
max_open_age => INT
Limit the maximum age of open transactions (in seconds). If this limit is reached, in progress transactions will automatically be purged because it times out.
max_committed_age => INT
Limit the maximum age of committed transactions (in seconds). If this limit is reached, the old transactions will start to be purged.
Start a new transaction.
Arguments: tx_id (str, required, unless already supplied via _tx_id()), twopc (bool, optional, currently must be false since distributed transaction is not yet supported), summary (optional).
TM will create an entry for this transaction in its database.
Record a function call. This method needs to be called before function does any step.
Arguments: tx_id, f (optional, function name, will be retrieved from caller(1) if not specified, assuming the call is from the function itself), args (required, function arguments).
TM will create an entry for this call in its database.
Return call ID in enveloped response.
Record an undo step. This method needs to be called before performing a step.
Arguments: tx_id, call_id, data (an array).
Record a redo step. This method needs to be called before performing an undo step.
Will return (in enveloped response) an array of undo steps, e.g. [200, "OK", [["step1"], ["step2", "arg"], ...]] for the particular call.
Arguments: tx_id, call_id.
Will return (in enveloped response) an array of redo steps, e.g. [200, "OK", [["step2"], ["step1"], ...]] for the particular call.
Arguments: tx_id
Arguments: tx_id, sp (optional, savepoint name to rollback to a specific savepoint only).
Currently rolling back to a savepoint is not implemented.
Currently will return 501 (not implemented). This TM does not support distributed transaction.
Arguments: tx_id, sp (savepoint name).
Currently not implemented.
List transactions. Return an array of results sorted by creation date (in ascending order).
Arguments: detail (bool, default 0, whether to return transaction records instead of just a list of transaction ID's).
Discard (forget) a committed transaction. The transaction will no longer be undoable.
Discard (forget) all committed transactions.
Riap::Transaction
Perinci::Access::InProcess
Rinci::function::Undo
Rinci::function::Transaction
This module has Rinci metadata.
None are exported by default, but they are exportable.
Steven Haryanto <stevenharyanto@gmail.com>
This software is copyright (c) 2012 by Steven Haryanto.
This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.
To install Perinci, copy and paste the appropriate command in to your terminal.
cpanm
cpanm Perinci
CPAN shell
perl -MCPAN -e shell install Perinci
For more information on module installation, please visit the detailed CPAN module installation guide.