ioredis.js

/*
 * Copyright Elasticsearch B.V. and other contributors where applicable.
 * Licensed under the BSD 2-Clause License; you may not use this file except in
 * compliance with the BSD 2-Clause License.
 */

'use strict';

// Instrumentation of the 'ioredis' package:
// https://github.com/luin/ioredis
// https://github.com/luin/ioredis/blob/master/API.md

const semver = require('semver');

const constants = require('../../constants');
const { getDBDestination } = require('../context');
const shimmer = require('../shimmer');

const TYPE = 'db';
const SUBTYPE = 'redis';
const ACTION = 'query';
const hasIoredisSpanSym = Symbol('ElasticAPMHasIoredisSpan');

module.exports = function (ioredis, agent, { version, enabled }) {
  if (!enabled) {
    return ioredis;
  }
  if (!semver.satisfies(version, '>=2.0.0 <6.0.0')) {
    agent.logger.debug(
      'ioredis version %s not supported - aborting...',
      version,
    );
    return ioredis;
  }

  const ins = agent._instrumentation;

  agent.logger.debug('shimming ioredis.prototype.sendCommand');
  shimmer.wrap(ioredis.prototype, 'sendCommand', wrapSendCommand);
  return ioredis;

  function wrapSendCommand(origSendCommand) {
    return function wrappedSendCommand(command) {
      if (!command || !command.name || !command.promise) {
        // Doesn't look like an ioredis.Command, skip instrumenting.
        return origSendCommand.apply(this, arguments);
      }
      if (command[hasIoredisSpanSym]) {
        // Avoid double-instrumenting a command when ioredis *re*-calls
        // sendCommand for queued commands when "ready".
        return origSendCommand.apply(this, arguments);
      }

      agent.logger.debug(
        { command: command.name },
        'intercepted call to ioredis.prototype.sendCommand',
      );
      const span = ins.createSpan(
        command.name.toUpperCase(),
        TYPE,
        SUBTYPE,
        ACTION,
        { exitSpan: true },
      );
      if (!span) {
        return origSendCommand.apply(this, arguments);
      }

      command[hasIoredisSpanSym] = true;

      const options = this.options || {}; // `this` is the `Redis` client.
      span._setDestinationContext(getDBDestination(options.host, options.port));
      span.setDbContext({ type: 'redis' });

      const spanRunContext = ins.currRunContext().enterSpan(span);
      command.promise.then(
        () => {
          span.end();
        },
        ins.bindFunctionToRunContext(spanRunContext, (err) => {
          span._setOutcomeFromErrorCapture(constants.OUTCOME_FAILURE);
          agent.captureError(err, { skipOutcome: true });
          span.end();
        }),
      );
      return ins.withRunContext(
        spanRunContext,
        origSendCommand,
        this,
        ...arguments,
      );
    };
  }
};