Function deno_core::op_async [−][src]
pub fn op_async<F, V, R, RV>(op_fn: F) -> Box<OpFn> where
F: Fn(Rc<RefCell<OpState>>, V, Option<ZeroCopyBuf>) -> R + 'static,
V: DeserializeOwned,
R: Future<Output = Result<RV, AnyError>> + 'static,
RV: Serialize + 'static,
Creates an op that passes data asynchronously using JSON.
The provided function op_fn
has the following parameters:
Rc<RefCell<OpState>
: the op state, can be used to read/write resources in the runtime from an op.V
: the deserializable value that is passed to the Rust function.BufVec
: raw bytes passed along, usually not needed if the JSON value is used.
op_fn
returns a future, whose output is a serializable value. This value will be asynchronously
returned to JavaScript.
When registering an op like this…
ⓘ
let mut runtime = JsRuntime::new(...); runtime.register_op("hello", deno_core::op_async(Self::hello_op));
…it can be invoked from JS using the provided name, for example:
Deno.core.ops();
let future = Deno.core.opAsync("function_name", args);
The Deno.core.ops()
statement is needed once before any op calls, for initialization.
A more complete example is available in the examples directory.