dd-trace/packages/datadog-plugin-grpc/src/util.js

Datadog APM tracing client for JavaScript

'use strict'

const pick = require('../../datadog-core/src/utils/src/pick')
const log = require('../../dd-trace/src/log')

module.exports = {
  getMethodMetadata (path, kind) {
    const tags = {
      path,
      kind,
      name: '',
      service: '',
      package: ''
    }

    if (typeof path !== 'string') return tags

    const methodParts = path.split('/')

    if (methodParts.length > 2) {
      const serviceParts = methodParts[1].split('.')
      const name = methodParts[2]
      const service = serviceParts.pop()
      const pkg = serviceParts.join('.')

      tags.name = name
      tags.service = service
      tags.package = pkg
    } else {
      tags.name = methodParts.at(-1)
    }

    return tags
  },

  addMetadataTags (span, metadata, filter, type) {
    if (!metadata || typeof metadata.getMap !== 'function') return

    const values = filter(metadata.getMap())

    for (const key in values) {
      span.setTag(`grpc.${type}.metadata.${key}`, values[key])
    }
  },

  // TODO: extract this to shared utils and add unit tests
  getFilter (config, filter) {
    if (typeof config[filter] === 'function') {
      return config[filter]
    }

    if (Array.isArray(config[filter])) {
      return element => pick(element, config[filter])
    }

    if (config.hasOwnProperty(filter)) {
      log.error('Expected \'%s\' to be an array or function.', filter)
    }

    return () => ({})
  }
}