Using Serde Attributes
One of the main aims of this library is compatibility with Serde. Any generated schema should match how serde_json would serialize/deserialize to/from JSON. To support this, Schemars will check for any #[serde(...)]
attributes on types that derive JsonSchema
, and adjust the generated schema accordingly.
The list of supported #[serde]
attributes are documented here.
use schemars::{schema_for, JsonSchema};
use serde::{Deserialize, Serialize};
#[derive(Deserialize, Serialize, JsonSchema)]
#[serde(rename_all = "camelCase", deny_unknown_fields)]
pub struct MyStruct {
#[serde(rename = "myNumber")]
pub my_int: i32,
pub my_bool: bool,
#[serde(default)]
pub my_nullable_enum: Option<MyEnum>,
}
#[derive(Deserialize, Serialize, JsonSchema)]
#[serde(untagged)]
pub enum MyEnum {
StringNewType(String),
StructVariant { floats: Vec<f32> },
}
fn main() {
let schema = schema_for!(MyStruct);
println!("{}", serde_json::to_string_pretty(&schema).unwrap());
}
Click to see the output JSON schema...
{
"$schema": "http://json-schema.org/draft-07/schema#",
"title": "MyStruct",
"type": "object",
"required": [
"myBool",
"myNumber"
],
"properties": {
"myBool": {
"type": "boolean"
},
"myNullableEnum": {
"default": null,
"anyOf": [
{
"$ref": "#/definitions/MyEnum"
},
{
"type": "null"
}
]
},
"myNumber": {
"type": "integer",
"format": "int32"
}
},
"additionalProperties": false,
"definitions": {
"MyEnum": {
"anyOf": [
{
"type": "string"
},
{
"type": "object",
"required": [
"floats"
],
"properties": {
"floats": {
"type": "array",
"items": {
"type": "number",
"format": "float"
}
}
}
}
]
}
}
}