nttgin-BGPalerter/monitors/monitorVisibility.js

/*
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 * Copyright (c) 2019, NTT Ltd.
 * All rights reserved.
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 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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import Monitor from "./monitor";

export default class MonitorVisibility extends Monitor {

    constructor(name, channel, params, env){
        super(name, channel, params, env);
        this.thresholdMinPeers = (params && params.thresholdMinPeers != null) ? params.thresholdMinPeers : 10;
        if (params.threshold) {
            this.logger.log({
                level: 'error',
                message: "The parameter threshold has been replaced by thresholdMinPeers and it will be soon deprecated."
            });
            this.thresholdMinPeers = params.threshold;
        }
        this.updateMonitoredPrefixes();
    };

    updateMonitoredPrefixes = () => {
        this.monitored = this.input.getMonitoredPrefixes();
        this.monitoredSimpleArray = this.monitored.map(item => item.prefix);
    };

    filter = (message) => {
        // Based on exact match only
        return message.type === 'withdrawal'
            && this.monitoredSimpleArray.includes(message.prefix);
    };

    squashAlerts = (alerts) => {
        const peers = [...new Set(alerts.map(alert => alert.matchedMessage.peer))].length;

        if (peers >= this.thresholdMinPeers) {
            return (peers === 1) ?
                `The prefix ${alerts[0].matchedMessage.prefix} (${alerts[0].matchedRule.description}) it's no longer visible (withdrawn) from the peer ${alerts[0].matchedMessage.peer}.` :
                `The prefix ${alerts[0].matchedMessage.prefix} (${alerts[0].matchedRule.description}) has been withdrawn. It is no longer visible from ${peers} peers.`;
        } else {
            return false;
        }
    };

    monitor = (message) =>
        new Promise((resolve, reject) => {

            const messagePrefix = message.prefix;
            const matchedRule = this.getMoreSpecificMatch(messagePrefix);

            if (matchedRule && matchedRule.prefix === messagePrefix) {

                let key = matchedRule.prefix;

                this.publishAlert(key,
                    `The prefix ${matchedRule.prefix} has been withdrawn.`,
                    matchedRule.asn.getId(),
                    matchedRule,
                    message,
                    {});
            }

            resolve(true);
        });

}