TransactionManager

[dmccloskey]

Description

As a user, I would like to be able to make transactions against the TensorCollection. I would like to be able to specify commits and rollbacks. I would like to be able to submit transactions in the form of a lambda function that returns an optional TensorCollection "view" if appropriate.

Objectives

• [x] Commit and rollback mechanisms both on disk (i.e, write changed shards to disk) and in memory (i.e., apply view changes to tensor tables)
• [x] Transaction execution using lambda functions
• [x] Undo and Redo log
• [x] ACID transactions using e.g., atomics or scopedGuards

Validation

• [ ] Unit test coverage
• [ ] Passing unit tests
• [ ] Win/Linux builds

[dmccloskey]

Notes 2019-05-21 on ACID

• using Atomic: http://collaboration.cmc.ec.gc.ca/science/rpn/biblio/ddj/Website/articles/DDJ/2007/0712/071101cg01/071101cg01.html
• memento pattern: https://en.wikipedia.org/wiki/Memento_pattern
• TM http://collaboration.cmc.ec.gc.ca/science/rpn/biblio/ddj/Website/articles/DDJ/2007/0712/071101cg01/071101cg01.html
• STM https://gist.github.com/graninas/c7e0a603f3a22c7e85daa4599bf92525
• ScopeGuard https://github.com/ricab/scope_guard
• SharedPtrs https://stackoverflow.com/questions/10270328/the-simplest-and-neatest-c11-scopeguard and https://ideone.com/q8AxNt