bookbrainz/bookbrainz-site

import * as Influx from 'influx';
import log from 'log';

// Adapted from https://node-influx.github.io/manual/tutorial.html
function init(app, config) {
    const influxConfig = config.influx;

    const influx = new Influx.InfluxDB({
        database: influxConfig.database || 'bookbrainz',
        host: influxConfig.host || 'localhost',
        password: 'grafana',
        schema: [
            {
                fields: {
                    duration: Influx.FieldType.INTEGER
                },
                measurement: 'response_times',
                tags: [
                    'domain',
                    'path',
                    'status',
                    'verb'
                ]
            }
        ],
        username: 'grafana'
    });

    app.use((req, res, next) => {
        const start = Date.now();

        res.on('finish', () => {
            const duration = Date.now() - start;

            const data = {
                fields: {duration},
                measurement: 'response_times',
                tags: {
                    domain: influxConfig.domain || 'localhost',
                    path: req.path,
                    status: res.statusCode,
                    verb: req.method
                }
            };

            influx.writePoints([
                data
            ]).catch(err => {
                log.error(`Error saving data to InfluxDB! ${err.stack}`);
            });
        });

        return next();
    });
}

export default init;