pomelo-upgrade/lib/filters/rpc/toobusy.js

网易Pomelo升级版本

/**
 * Filter for rpc log.
 * Reject rpc request when toobusy
 */
const rpcLogger = require('pomelo-logger-upgrade').getLogger('rpc_log', __filename);
let toobusy = null;

const DEFAULT_MAXLAG = 70;

module.exports = function(maxLag)
{
    return new Filter(maxLag || DEFAULT_MAXLAG);
};

const Filter = function(maxLag)
{
    try
    {
        toobusy = require('toobusy');
    }
    catch (e)
    {
    }
    if (toobusy)
    {
        toobusy.maxLag(maxLag);
    }
};

Filter.prototype.name = 'toobusy';

/**
 * Before filter for rpc
 */
Filter.prototype.before = function(serverId, msg, opts, next)
{
    opts = opts || {};
    if (Boolean(toobusy) && toobusy())
    {
        rpcLogger.warn(`Server too busy for rpc request, serverId:${serverId} msg: ${msg}`);
        const err = new Error(`Backend server ${serverId} is too busy now!`);
        err.code = 500;
        next(err);
    }
    else
    {
        next();
    }
};