A wrapper which can internally call faas and return the result

wrapper_for_faas_call_example.js

function searchBytes(_haystack_array_buffer, _needle_array_buffer, _wasm_id, _function_name) {
    return new Promise(function(resolve, reject) {
        var needle = new Uint8Array(_needle_array_buffer);
        var haystack = new Uint8Array(_haystack_array_buffer);
        needle_length = needle.length;
        haystack_length = haystack.length;
        needle_length_string = needle_length.toString();
        for (i = needle_length_string.length; i < 10; i++) {
            needle_length_string = "0" + needle_length_string;
        }
        if (needle_length < 1 || needle_length > 9999999999 || needle_length > haystack_length) {
            alert("The needle's length is not correct, must be between 1 and 9999999999");
        } else {
            var base_array = needle_length_string.split('');
            for (i = 0; i < base_array.length; i++) base_array[i] = +base_array[i] | 0;
            console.log(base_array);
        }
        var buffer_to_go = new ArrayBuffer(10 + needle_length + haystack_length);
        var array_to_go = new Uint8Array(buffer_to_go);
        array_to_go.set(base_array);
        array_to_go.set(needle, 10);
        array_to_go.set(haystack, 10 + needle_length);

        var url = "https://rpc.ssvm.secondstate.io:8081/api/run/" + _wasm_id + "/" + _function_name;

        var xhr = new XMLHttpRequest();

        xhr.onreadystatechange = function() {
            if (xhr.readyState === 4) {
                resolve(xhr.response);
            }
        }

        xhr.open('POST', url, true);
        xhr.setRequestHeader("Content-Type", "application/octet-stream");
        xhr.send(buffer_to_go);
    });
}

// Start Skip. Generate some data (but you would already have the ArrayBuffer with data pre-filled)
var buffer_1 = new ArrayBuffer(1000000);
var buffer_2 = new ArrayBuffer(1000000);
var needle = new Uint8Array(buffer_1);
var haystack = new Uint8Array(buffer_2);
needle.fill(111);
haystack.fill(222);
// End Skip.
//
// You would just need to run the following code
searchBytes(buffer_2, buffer_1, 226, "search_bytes_single_input")
    .then(function(the_result) {
        console.log("Result: " + the_result);
    })
    .catch(function() {
        console.log("Error");
    });