https://github.com/helium/erlang-xorf

Erlang binding to the xorf crate
https://github.com/helium/erlang-xorf

Last synced: 6 days ago
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Erlang binding to the xorf crate

• Host: GitHub
• URL: https://github.com/helium/erlang-xorf
• Owner: helium
• License: apache-2.0
• Created: 2022-01-14T15:09:48.000Z (almost 3 years ago)
• Default Branch: main
• Last Pushed: 2022-01-21T20:23:10.000Z (almost 3 years ago)
• Last Synced: 2024-09-24T13:36:18.326Z (about 2 months ago)
• Language: Rust
• Size: 1.65 MB
• Stars: 0
• Watchers: 25
• Forks: 2
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • Contributing: CONTRIBUTING.md
  • License: LICENSE

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README

        
# erlang-xorf 

[![ci](https://github.com/helium/erlang-xorf/actions/workflows/erlang.yml/badge.svg)](https://github.com/helium/erlang-xorf/actions/workflows/erlang.yml)

[![codecov](https://codecov.io/gh/helium/erlang-xorf/branch/main/graph/badge.svg?token=PHV5HEFNRT)](https://codecov.io/gh/helium/erlang-xorf)

[![hex.pm](https://img.shields.io/hexpm/v/erlang-xorf)](https://hex.pm/packages/erlang-xorf)

This library is a NIF wrapper for the [xorf](https://crates.io/crates/xorf)

family of xor filters.

Both binary fuses and xor filters are suported in 8 16, and 32 bits per entry.

**NOTE**: The initialization list to a filter must be a unique list of 64 bit

integers. Use a good hashing function over your data and make sure to dedupe it

before passing it into the `xorf:new/2` functions. Lists with duplicates may

cause undefined behavior.

## Table of Contents

- [Table of Contents](#table-of-contents)

- [Installation](#installation)

- [Example Usage](#example-usage)

- [Serialization](#serialization)

## Installation

Install from [hex.pm](https://hex.pm/packages/xorf).

For rebar3:

```erlang

%% rebar.config

{deps, [

  {xorf, "1.0.0"}

]}.

```

For Mix:

```elixir

## mix.exs

defp deps do

  [

    {:xorf, "~> 1.0.0"}

  ]

end

```

## Example Usage

**NOTE** The list of integers given to `xorf:new/2` must be deduped to avoid

undefined behavior.

For an xor filter:

```erlang

{ok, Filter} = xorf:new({exor, 8}, [1, 2, 3]),

true   = xorf:contains(Filter, 1),

false  = xorf:contains(Filter, 5),

```

Note that the number of bits per entry implies the likelihood of false positives

in the resulting filter.

For a binary fuse:

```erlang

{ok, Filter} = xorf:new({binary_fuse, 8}, [1, 2, 3]),

true   = xorf:contains(Filter, 1),

false  = xorf:contains(Filter, 5),

```

## Serialization

Binary serialization and deserialization is achieved using the [bincode](https://github.com/bincode-org/bincode).

For example, given a binary for an 8 bit binary fuse:

```erlang

{ok, Bin} = xorf:to_bin(Filter),

{ok, DFilter} = xorf:from_bin({binary_fuse, 8}, Bin),

true   = xorf:contains(DFilter, 1),

false  = xorf:contains(DFilter, 5),

```