Summary:
Certain types of things we should be storing in edges (notably, Task X depends on Task Y) should always be acyclic. Allow `PhabricatorEdgeEditor` to enforce this, since we can't correctly enforce it outside of the editor without being vulnerable to races.
Each edge type can be marked acyclic. If an edge type is acyclic, we perform additional steps when writing new edges of that type:
- We acquire a global lock on the edge type before performing any reads or writes. This ensures we can't produce a cycle as a result of a race where two edits add edges which independently do not produce a cycle, but do produce a cycle when combined.
- After performing writes but before committing transactions, we load the edge graph for each acyclic type and verify that it is, in fact, acyclic. If we detect cycles, we abort the edit.
- When we're done, we release the edge type locks.
This is a relatively high-complexity change, but gives us a simple way to flag an edge type as acyclic in a robust way.
Test Plan: Ran unit tests.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T1162
Differential Revision: https://secure.phabricator.com/D2940
Summary:
- See D2741.
- When EdgeEditor performs edits, emit events.
- Listen for Maniphest edge events and save the changes as transactions.
- Do all this in a reasonably generic way that won't take too much rewriting as we use edges more generally.
Test Plan: Attached and detached commits from tasks, saw reasonable-looking transactions spring into existence.
Reviewers: btrahan, davidreuss
Reviewed By: btrahan
CC: aran
Differential Revision: https://secure.phabricator.com/D2906
Summary:
- `kill_init.php` said "Moving 1000 files" - I hope that this is not some limit in `FileFinder`.
- [src/infrastructure/celerity] `git mv utils.php map.php; git mv api/utils.php api.php`
- Comment `phutil_libraries` in `.arcconfig` and run `arc liberate`.
NOTE: `arc diff` timed out so I'm pushing it without review.
Test Plan:
/D1234
Browsed around, especially in `applications/repository/worker/commitchangeparser` and `applications/` in general.
Auditors: epriestley
Maniphest Tasks: T1103
Summary: Use Edges to attach Commits and Tasks. Note, no "edit attached commits" interface from tasks yet since the search backend needs a little work to list commits in a sensible way.
Test Plan: Attached commits to tasks. Looked at commits, looked at tasks.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T904
Differential Revision: https://secure.phabricator.com/D2105
Summary:
We have a lot of cases where we store object relationships, but it's all kind of messy and custom. Some particular problems:
- We go to great lengths to enforce order stability in Differential revisions, but the implementation is complex and inelegant.
- Some relationships are stored on-object, so we can't pull the inverses easily. For example, Maniphest shows child tasks but not parent tasks.
- I want to add more of these and don't want to continue building custom stuff.
- UIs like the "attach stuff to other stuff" UI need custom branches for each object type.
- Stuff like "allow commits to close tasks" is notrivial because of nonstandard metadata storage.
Provide an association-like "edge" framework to fix these problems. This is nearly identical to associations, with a few differences:
- I put edge metadata in a separate table and don't load it by default, to keep edge rows small and allow large metadata if necessary. The on-edge metadata seemed to get abused a lot at Facebook.
- I put a 'seq' column on the edges to ensure they have an explicit, stable ordering within a source and type.
This isn't actually used anywhere yet, but my first target is attaching commits to tasks for T904.
Test Plan: Made a mock page that used Editor and Query. Verified adding and removing edges, overwriting edges, writing and loading edge data, sequence number generation.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran, 20after4
Differential Revision: https://secure.phabricator.com/D2088
