@mmacedoeu did a good deal of work to show that Arc instead of Rc
wasn't too difficult in #656, and @rnewman pushed the refactoring
across the line in #659. However, we didn't flip the switch at that
time. For #673, we'd like to include TypedValue instances in errors,
and with error-chain (and failure) error types need to be 'Sync +
'Send, so we need Arc.
This builds on #659 and should also finish #656.
This innocuous looking change (upserts_ev -> upserts_e -> resolved in
all situations, rather than upserts_ev -> resolved in some situations)
is a significant change in semantics and assumptions in the
transactor. Witness the large comment being removed about the same
tempid resolving in different generations!
To support this change, we provide more holistic errors for
conflicting upserts, which entails collecting some (relatively
expensive) diagnostic data.
I left in some debug logging, simply since it shouldn't hurt in
general, and will likely be useful for the next bug we see in the
transactor.
We don't yet have a logging system for production use, but I'd like to
start experimenting with log, which seems to be (close to) a Rust
standard. We're already using it in mentat_cli.
:db/tx (and Datomic's version, :datomic/tx) suffer from the same
ambiguities that [a v] lookup references do -- determining the type of
the result is context sensitive. (In this case, is :db/tx a reference
to the current transaction ID, or is it a valid keyword?) This commit
addresses the ambiguity by introducing a notion of a transaction
functions, and provides a little scaffolding for adding more (should
the need arise). I left the scaffolding in place rather than handling
just (transaction-tx) because I started trying to
implement (transaction-instant) as well, which is more difficult --
see the comments.
It's worth noting that this approach generalizes more or less directly
to ?input variables, since those can be eagerly bound like the
implemented transaction function (transaction-tx).
* Pre: eliminate some occurrences of Rc, largely through the magic of Into.
* Pre: introduce FromRc to convert between refcounted types.
* Introduce ValueRc as an abstraction over Rc/Arc choice.
* Move Cloned to core.
* Move CString-creation methods to TypedValue.
* Finish transition.
* Pre: clean up core/src/lib.rs.
* Pre: use indexmap 1.0 in db and query-projector.
* Change rel results to be a RelResult instance, not a Vec<Vec<TypedValue>>.
This avoids memory fragmentation and improves locality by using a single
heap-allocated vector for all bindings, rather than a separate
heap-allocated vector for each row.
We hide this abstraction behind the `RelResult` type, which tracks the
stride length (width) of each row.
* Don't allocate temporary vectors when projecting RelResults.
`tx-ids` allows to enumerate transaction IDs efficiently.
`tx-data` allows to extract transaction log data efficiently.
We might eventually allow to filter by impacted attribute sets as well.
Some parts of the query engine and transactor need to know whether an
attribute is a component attribute, and sometimes want to do so in
a generated SQL query. This is one way to do that.
* Tidy up and add txid at beginning of transaction
* Add ffi crate and new_store function
* Add register and unregister observer FFI, Store and Conn functions.
Also add android logging facilities
* Add function for fetching entids for attribute strings
* Add functions for iterating through TxReports
* Add sync to ffi boundary
* Move Extern types from submodule to lib in FFI.
For some reason, if these types are in a submodule, even if they are publically used, the functions inside the FFI are not found in
Android. Works for iOS though. To be investigated later....
* Return to passing TxReports to observer function.
Also, remove some debug
* Expose DateTime and Utc publically
* Use Store in observer tests
Simplify.
This has a watcher collect txid -> AttributeSet mappings each time a
transact occurs. On commit we retrieve those mappings and hand them over
to the observer service, which filters them and packages them up for
dispatch.
Tidy up
