service-model/dispatcher/defaultOperationInvoker.js

An object oriented web service framework inspired by Windows Communication Foundation.

/**
 * @hidden
 */
var DefaultOperationInvoker = (function () {
    function DefaultOperationInvoker(description) {
        /**
         * Timeout for operation. Defaults to 60,000ms (1 minute).
         */
        this.timeout = 60000;
        if (!description) {
            throw new Error("Missing required argument 'operationDescription'.");
        }
        this._method = description.method;
        var parameters = description.method.parameters || [];
        // do not include callback in parameter count
        this._parameterCount = parameters.length - 1;
    }
    DefaultOperationInvoker.prototype.invoke = function (instance, args, callback) {
        var _this = this;
        if (!instance) {
            throw new Error("Missing required argument 'instance'.");
        }
        if (!args) {
            throw new Error("Missing required argument 'args'.");
        }
        if (args.length != this._parameterCount) {
            process.nextTick(function () { return callback(new Error("Wrong number of arguments for operation.")); });
            return;
        }
        // asynchronous invoke
        var timeout = false, finished = false;
        if (this.timeout) {
            var timeoutHandle = setTimeout(function () {
                if (finished)
                    return;
                timeout = true;
                callback(new Error("Timeout of " + _this.timeout + "ms exceeded while invoking operation."));
            }, this.timeout);
        }
        var done = function (err, result) {
            if (timeout)
                return;
            if (timeoutHandle) {
                clearTimeout(timeoutHandle);
            }
            if (finished) {
                throw new Error("Callback already called.");
            }
            finished = true;
            callback(err, result);
        };
        this._method.invoke(instance, args.concat(done));
    };
    return DefaultOperationInvoker;
})();
exports.DefaultOperationInvoker = DefaultOperationInvoker;