'use strict';
|
|
const co = require('co');
|
const is = require('is-type-of');
|
const stringify = require('json-stringify-safe');
|
|
const MAX_REQUEST_ID = Math.pow(2, 30); // avoid write big integer
|
const empty = () => {};
|
|
let id = 0;
|
|
function nextId() {
|
id += 1;
|
if (id >= MAX_REQUEST_ID) {
|
id = 1;
|
}
|
return id;
|
}
|
|
/**
|
* generate requestId
|
*
|
* @return {Number} requestId
|
*/
|
exports.nextId = nextId;
|
|
// for unittest
|
exports.setId = val => {
|
id = val;
|
};
|
|
/**
|
* event delegate
|
*
|
* @param {EventEmitter} from - from object
|
* @param {EventEmitter} to - to object
|
* @return {void}
|
*/
|
exports.delegateEvents = (from, to) => {
|
// ignore the sdk-base defaultErrorHandler
|
// https://github.com/node-modules/sdk-base/blob/master/index.js#L131
|
if (from.listeners('error').length <= 1) {
|
from.on('error', empty);
|
}
|
|
from.emit = new Proxy(from.emit, {
|
apply(target, thisArg, args) {
|
target.apply(from, args);
|
to.emit.apply(to, args);
|
return thisArg;
|
},
|
});
|
};
|
|
function formatKey(reg) {
|
return stringify(reg);
|
}
|
|
/**
|
* normalize object to string
|
*
|
* @param {Object} reg - reg object
|
* @return {String} key
|
*/
|
exports.formatKey = formatKey;
|
|
/**
|
* call a function, support common function, generator function, or a function returning promise
|
*
|
* @param {Function} fn - common function, generator function, or a function returning promise
|
* @param {Array} args - args as fn() paramaters
|
* @return {*} data returned by fn
|
*/
|
exports.callFn = async function(fn, args) {
|
args = args || [];
|
if (!is.function(fn)) return;
|
if (is.generatorFunction(fn)) {
|
return await co(function* () {
|
return yield fn(...args);
|
});
|
}
|
const r = fn(...args);
|
if (is.promise(r)) {
|
return await r;
|
}
|
return r;
|
};
|
|
exports.findMethodName = (descriptors, type) => {
|
for (const method of descriptors.keys()) {
|
const descriptor = descriptors.get(method);
|
if (descriptor.type === 'delegate' && descriptor.to === type) {
|
return method;
|
}
|
}
|
return null;
|
};
|
