A JSON Schema validator implementation. It compiles schema into a validation tree to have validation as fast as possible.
Supported drafts:
- Draft 7
- Draft 6
- Draft 4 (except optional bignum.json test case)
```toml
jsonschema = "0.3" ```
To validate documents against some schema and get validation errors (if any):
```rust 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):
```rust use jsonschema::isvalid; use serdejson::json;
fn main() { let schema = json!({"maxLength": 5}); let instance = json!("foo"); assert!(is_valid(&schema, &instance)); } ```
Or use a compiled schema (preferred):
```rust use jsonschema::{JSONSchema, Draft}; use serde_json::json;
fn main() { let schema = json!({"maxLength": 5}); let instance = json!("foo"); // Draft is detected automatically with fallback to Draft7 let compiled = JSONSchema::compile(&schema, None); assert!(compiled.is_valid(&instance)); } ```
There is a comparison with other JSON Schema validators written in Rust - jsonschema_valid and valico.
Test machine i8700K (12 cores), 32GB RAM.
Performance of jsonschema::JSONSchema.is_valid. Ratios are given against compiled jsonschema:
canada_schema.json and canada.json)small_schema.json and small_valid.json)small_schema.json and small_invalid.json)| Case | jsonschema_valid | valico | jsonschema (not compiled) | jsonschema (compiled) | | ------------- | ---------------------- | ----------------------- | ------------------------- | --------------------- | | Big valid | 56.746 ms (x187.2) | 149.49 ms (x493.17) | 317.14 us (x1.04) | 303.12 us | | Small valid | 2.23 us (x14.92) | 3.87 us (x25.9) | 3.76 us (x25.17) | 149.38 ns | | Small invalid | 515.22 ns (x85.58) | 4.08 us (x677.74) | 3.63 us (x602.99) | 6.02 ns |
As you can see the compiled version is faster, especially for large inputs. However, not-compiled version is slower
on smaller inputs than jsonschema_valid.
You can find benchmark code in benches/jsonschema.rs
NOTE. This library is in early development.