### Storage
Storage features provdies a single trait of ```RadStorage``` which implements
```update``` and ```extract```.
You can call update and extract method with update and extract macro respectively.
#### Example
You need to import [Serde](https://github.com/serde-rs/serde) in your proejct
for stroage.
Create storage struct
```rust
use serde::{Serialize,Deserialize};
use r4d::{StorageOutput, StorageResult};
#[derive(Serialize,Deserialize)]
pub struct PlotModel {
// informations
...
}
impl RadStorage for PlotModel {
fn update(&mut self, args : &[String]) -> StorageResult<()> {
// Update logics
}
// $extract() macro calls extract method with the serialize value of "false"
fn extract(&mut self, serialize: bool) -> StorageResult<Option<StorageOutput>> {
if serialize {
Ok(Some(StorageOutput::Binary(bincode::serialize(self)?)))
} else {
Ok(Some(StorageOutput::Text(serde_json::to_string(self)?)))
}
}
}
```
And add storage to processor before processing.
```rust
processor.set_storage(Box::new(PlotModel::default()));
```