Membrane provides a wrapper for filtering data with simplicity and efficiently.
It filters out list of structs or maps that satisfy the query. The Query is inspired by Mongo, hence there's a lot of similarities. To learn more please visit our documentation https://hexdocs.pm/membrane/Membrane.html .
To install just add the module to your mix file.
def deps do
[
...
{:membrane, "~> 0.1.0"}
]
end
Membrane currently provides a single function named filter for filtering the data
iex> data = [
%Person{id: 1, name: "Bob", action: "talk", age: 30},
%Person{id: 3, name: "Helen", action: "talk", age: 30},
%Dog{id: 1, name: "Rocky", action: "bark", age: 10},
%Cat{id: 3, name: "Rocky", action: "meow", age: 6},
%Chair{id: 10, age: 3},
%{id: 1, type: "car", age: 12}
]
# The query matches all objects with `id` as 1
iex> Membrane.filter(data, id: 1)
[
%{id: 1, type: "car", age: 12},
%Dog{id: 1, name: "Rocky", action: "bark", age: 10},
%Person{id: 1, name: "Bob", action: "talk", age: 30},
]
As you can notice Membrane.filter is independent of structs or maps in the data. This is because all structs are just bare maps
It also supports complex queries. Say for the same data.
# The query matches all objects with `age` greater than 8 and has `action` attribute.
iex> Membrane.filter(data, age: [gt: 8], action: :exists)
[
%Dog{id: 1, name: "Rocky", action: "bark", age: 10},
%Person{id: 3, name: "Helen", action: "talk", age: 30},
%Person{id: 1, name: "Bob", action: "talk", age: 30},
]
- Logical and Comparision Operations
- List based Operations
- Filtering based on existence of an attribute
- Not Operation
- Comparision between attributes of a struct
- Renaming of attribute names ( Final output has to be a list of maps )
- Filtering struct which has query keywords as attributes.
It's a new project so please feel free to contribute. Reporting bugs will also help.
The source code is released under MIT License. Check the License file for more information