# An Erlang Binding to FoundationDB

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This project is a NIF wrapper for the FoundationDB C API. Documentation on
the main API can be found [here][fdb_docs].

This project also provides a conforming implementation of the [Tuple] and
[Directory] layers.

[fdb_docs]: https://apple.github.io/foundationdb/api-c.html
[Tuple]: https://github.com/apple/foundationdb/blob/master/design/tuple.md
[Directory]: https://apple.github.io/foundationdb/developer-guide.html#directories

The original development of this project occurred as [apache/couchdb-erlfdb](https://github.com/apache/couchdb-erlfdb). This fork
was created in early 2024 to continue development of the project.

## Building

Assuming you have installed the FoundationDB C API library, building erlfdb
is as simple as:

    $ rebar3 compile

Alternatively, adding erlfdb as a rebar dependency should Just Work ®.

Documentation for installing FoundationDB can be found [here for macOS]
or [here for Linux].

[here for macOS]: https://apple.github.io/foundationdb/getting-started-mac.html
[here for Linux]: https://apple.github.io/foundationdb/getting-started-linux.html

## Quick Example

A simple example showing how to open a database and read and write keys:

```erlang

Eshell V9.3.3.6  (abort with ^G)
1> Db = erlfdb:open(<<"/usr/local/etc/foundationdb/fdb.cluster">>).
{erlfdb_database,#Ref<0.2859661758.3941466120.85406>}
2> ok = erlfdb:set(Db, <<"foo">>, <<"bar">>).
ok
3> erlfdb:get(Db, <<"foo">>).
<<"bar">>
4> erlfdb:get(Db, <<"bar">>).
not_found
```

## Binding Tester

FoundationDB has a custom binding tester that can be used to test whether
changes have broken compatibility. See the [BINDING_TESTER](BINDING_TESTER.md)
documentation for instructions on building and running that system.