Trait Policy

Source

pub trait Policy:
    Send
    + Sync
    + Debug {
    // Provided methods
    fn check_event(&self, _event: PolicyEvent<'_>) -> Result<()> { ... }
    fn check_value(&self, _value: &Value) -> Result<()> { ... }
}

Expand description

Pluggable “Safe YAML” policy.

Implementors override either or both check methods. The default implementations accept everything, so a policy that only cares about the post-parse value can leave Policy::check_event alone.

§Examples

use noyalib::policy::{Policy, PolicyEvent, PolicyEventKind};
use noyalib::{from_str_with_config, ParserConfig, Value, Result, Error};

#[derive(Debug, Default)]
struct DenyTabs;
impl Policy for DenyTabs {
    fn check_event(&self, ev: PolicyEvent<'_>) -> Result<()> {
        if ev.kind == PolicyEventKind::Scalar
            && ev.scalar.is_some_and(|s| s.contains('\t'))
        {
            return Err(Error::Deserialize("tab in scalar".into()));
        }
        Ok(())
    }
}

let cfg = ParserConfig::new().with_policy(DenyTabs);
let res: Result<Value> = from_str_with_config("k: \"a\\tb\"\n", &cfg);
assert!(res.is_err());