elastic-apm-node/lib/instrumentation/modules/@hapi/hapi.js

The official Elastic APM agent for Node.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';

var semver = require('semver');

var shimmer = require('../../shimmer');

var onPreAuthSym = Symbol('ElasticAPMOnPreAuth');

module.exports = function (hapi, agent, { version, enabled }) {
  if (!enabled) {
    return hapi;
  }
  if (!semver.satisfies(version, '>=17.9.0 <22.0.0')) {
    agent.logger.debug('@hapi/hapi@%s not supported, skipping', version);
    return hapi;
  }

  agent.setFramework({ name: 'hapi', version, overwrite: false });

  agent.logger.debug('shimming hapi.Server, hapi.server');
  shimmer.massWrap(hapi, ['Server', 'server'], function (orig) {
    return function (options) {
      var res = orig.apply(this, arguments);
      patchServer(res);
      return res;
    };
  });

  function patchServer(server) {
    // Hooks that are always allowed
    if (typeof server.on === 'function') {
      attachEvents(server);
    } else if (typeof server.events.on === 'function') {
      attachEvents(server.events);
    } else {
      agent.logger.debug('unable to enable hapi error tracking');
    }

    server.ext('onPreAuth', onPreAuth);
    server.ext('onPreResponse', onPreResponse);
    if (agent._conf.captureBody !== 'off') {
      server.ext('onPostAuth', onPostAuth);
    }
  }

  function attachEvents(emitter) {
    emitter.on('log', function (event, tags) {
      captureError('log', null, event, tags);
    });

    emitter.on('request', function (req, event, tags) {
      captureError('request', req, event, tags);
    });
  }

  function captureError(type, req, event, tags) {
    if (!event || !tags.error || event.channel === 'internal') {
      return;
    }

    // TODO: Find better location to put this than custom
    var payload = {
      custom: {
        tags: event.tags,
        internals: event.internals,
        // Moved from data to error in hapi 17
        data: event.data || event.error,
      },
      request: req && req.raw && req.raw.req,
    };

    var err = payload.custom.data;
    if (!(err instanceof Error) && typeof err !== 'string') {
      err = 'hapi server emitted a ' + type + ' event tagged error';
    }

    agent.captureError(err, payload);
  }

  function onPreAuth(request, reply) {
    agent.logger.debug('received hapi onPreAuth event');

    // Record the fact that the preAuth extension have been called. This
    // info is useful later to know if this is a CORS preflight request
    // that is automatically handled by hapi (as those will not trigger
    // the onPreAuth extention)
    request[onPreAuthSym] = true;

    if (request.route) {
      // fingerprint was introduced in hapi 11 and is a little more
      // stable in case the param names change
      // - path example: /foo/{bar*2}
      // - fingerprint example: /foo/?/?
      var fingerprint = request.route.fingerprint || request.route.path;

      if (fingerprint) {
        var name =
          (request.raw && request.raw.req && request.raw.req.method) ||
          (request.route.method && request.route.method.toUpperCase());

        if (typeof name === 'string') {
          name = name + ' ' + fingerprint;
        } else {
          name = fingerprint;
        }

        agent._instrumentation.setDefaultTransactionName(name);
      }
    }

    return reply.continue;
  }

  function onPostAuth(request, reply) {
    if (request.payload && request.raw && request.raw.req) {
      // Save the parsed req body to be picked up by getContextFromRequest().
      request.raw.req.payload = request.payload;
    }
    return reply.continue;
  }

  function onPreResponse(request, reply) {
    agent.logger.debug('received hapi onPreResponse event');

    // Detection of CORS preflight requests:
    // There is no easy way in hapi to get the matched route for a
    // CORS preflight request that matches any of the autogenerated
    // routes created by hapi when `cors: true`. The best solution is to
    // detect the request "fingerprint" using the magic if-sentence below
    // and group all those requests into on type of transaction
    if (
      !request[onPreAuthSym] &&
      request.route &&
      request.route.path === '/{p*}' &&
      request.raw &&
      request.raw.req &&
      request.raw.req.method === 'OPTIONS' &&
      request.raw.req.headers['access-control-request-method']
    ) {
      agent._instrumentation.setDefaultTransactionName('CORS preflight');
    }

    return reply.continue;
  }

  return hapi;
};