Transactions, Keys, and Values: an attempt at a generic interface for transactional key-value stores with different backends.
The interfaces are defined in the Trakeva module.
We have, for now, one DB implementation of the module type Trakeva.KEY_VALUE_STORE:
Trakeva_sqlite (in the separate library trakeva_sqlite) uses
Sqlite3-ocaml.Trakeva_postgresql (in the separate library trakeva_postgresql) uses
postgresql-ocamlTrakeva_of_uri (in the separate library trakeva_of_uri)
chooses dynamically between the 2 backends above thanks to the URI passed to
the Trakeva_of_uri.load function. The backends are optionally compiled so
they might be missing;load would then throw an exception.There is also a very basic in “in-memory” cache functor, adding a cache layer on
top of any key-value DB, cf. Trakeva_cache.
See also the repository smondet/trakeva
for issues/questions.
To install the libraries use opam:
opam install trakevaIf the packages sqlite3 and/or postgresql are installed, then the libraries
trakeva_sqlite and/or trakeva_postgresql will be picked-up for installation
too.
To build the development version from the repository, just run:
make configure
make(this will enable all backends and the tests).
The tests/benchmarks also depend on the
Sosa library
(opam install sosa).
To run the unit tests:
./trakeva_testsThe main test starts a temporary Postgresql server on port 4242, this can be
overridden with the environment variable POSTGRESQL_PORT.
To use an existing database server instead of creating one use the variable
POSTGRESQL_CONNECTION_INFO.
To run the benchmarks:
./trakeva_tests bench collection=100 kb=5 # quick bench
./trakeva_tests bench collection=1000 kb=20 # about a minute longTo build the documentation:
make docand checkout _doc/index.html.
See the issues #50, on the opam-repository and #21129 on Homebrew. So please use:
brew install pkg-config sqlite
export PKG_CONFIG_PATH=`find /usr/local/Cellar/sqlite -depth 1 | tail -n 1`/lib/pkgconfig
opam install sqlite3