jsonschema

Yet another JSON Schema validator implementation. It compiles schema into a validation tree to have validation as fast as possible.

To validate documents against some schema and get validation errors (if any):

use jsonschema::{JSONSchema, Draft};
use serde_json::json;

fn main() {
    let schema = json!({"maxLength": 5});
    let instance = json!("foo");
    let compiled = JSONSchema::compile(&schema, Some(Draft::Draft7));
    let result = compiled.validate(&instance);
    if let Err(errors) = result {
        for error in errors {
            println!("Validation error: {}", error)
        }   
    }
}

If you only need to know whether document is valid or not (which is faster):

use jsonschema::is_valid;
use serde_json::json;

fn main() {
    let schema = json!({"maxLength": 5});
    let instance = json!("foo");
    assert!(is_valid(&schema, &instance));
}

Or use a compiled schema (preferred):

use jsonschema::{JSONSchema, Draft};
use serde_json::json;

fn main() {
    let schema = json!({"maxLength": 5});
    let instance = json!("foo");
    let compiled = JSONSchema::compile(&schema, None);  // Draft is detected automatically with fallback to Draft7
    assert!(compiled.is_valid(&instance));
}

NOTE. This library is in early development.