Perfect New Relic Library for Linux

This project provides a Swift Agent SDK for New Relic.

This package builds with Swift Package Manager and is part of the Perfect project but can be used as an independent module.

Release Note

This project is only compatible with Ubuntu 16.04 and Swift 4.0 Tool Chain.

Quick Start

Please use Perfect Assistant to import this project, otherwise an install script is available for Ubuntu 16.04:

$ git clone
$ cd Perfect-libNewRelic-linux
$ sudo ./

During the installation, it will automatically ask for license key, application name, language and its version. Then it will install the command line newrelic-collector-client-daemon as a service which you can find the configuration on /usr/local/etc/newrelic.service.

Configure Package.swift:

.Package(url: "", majorVersion: 3)

Import library into your code ( NOTE Since Swift 4.0 on linux has a significant linker issue, so module PerfectNewRelic must be accompanied with Foundation):

import PerfectNewRelic
import Foundation

Aside of Swift - C syntax conversion differences, document can be found on New Relic Agent SDK


Post Installation & Configuration can be found on New Relic - Configuring the Agent SDK, please note that NewRelic instance is configured as Daemon Mode which is highly recommended because the Embedded-mode is still experimental.

If success, you can create NewRelic instance easily:

let nr = try NewRelic()
  • Create a function to receive status change notifications:
nr.registerStatus { code in
    guard let status = NewRelic.Status(rawValue: code) else {
        // something wrong here
    }//end guard
    switch status {
        case .STARTING: // New Relic Daemon Service is starting
        case .STARTED: // New Relic Daemon Service is started
        case .STOPPING: // New Relic Daemon Service is stopping
        default: // shutdown already
   }//end case
}//end callback

Limiting or disabling Agent SDK settings

According to New Relic Limiting or disabling Agent SDK Settings, the following settings are available in Perfect NewRelic:

If you want to ... Use this setting ...
Disable data collection during a transaction nr.enableInstrumentation(false)
Configure the number of trace segments collected in a transaction trace let t = try Transaction(nr, maxTraceSegments: 50) // // Only collect up to 50 trace segments

API Quick Help

Base on New Relic's Document of Using the Agent SDK, Perfect NewRelic library provides identically the same functions of New Relic Agent SDK in Swift:

Instruments & Profiling

Function recordMetric()
Demo try nr.recordMetric(name: "ActiveUsers", value: 25)
Description Record a custom metric.
Parameters - name: name of the metric.
- value: value of the metric.
Function recordCPU()
Demo try nr.recordCPU(timeSeconds: 5.0, usagePercent: 1.2)
Description Record CPU user time in seconds and as a percentage of CPU capacity.
Parameters - timeSeconds: Double, number of seconds CPU spent processing user-level code
- usagePercent: Double, CPU user time as a percentage of CPU capacity
Function recordMemory()
Demo try nr.recordMemory(megabytes: 32)
Description Record the current amount of memory being used.
Parameters - megabytes: Double, amount of memory currently being used


Transaction in Perfect NewRelic has been defined as a class, with constructior as below:

public init(_ instance: NewRelic,
    webType: Bool? = nil,
    category: String? = nil,
    name: String? = nil,
    url: String? = nil,
    attributes: [String: String],
    maxTraceSegments: Int? = nil
  ) throws

Constructor parameters:

  • instance: NewRelic instance, required.
  • webType: optional. true for WebTransaction and false for other. default is true.
  • category: optional. name of the transaction category, default is 'Uri'
  • name: optional. transaction name
  • url: optional. request url for a web transaction
  • attributes: optional. transaction attributes, pair of "name: value"
  • maxTraceSegments: optional. Set the maximum number of trace segments allowed in a transaction trace. By default, the maximum is set to 2000, which means the first 2000 segments in a transaction will create trace segments if the transaction exceeds the trace threshold (4 x apdex_t).

Demo of Transaction Class Initialization:

let nr = NewRelic()
let t = try Transaction(nr, webType: false,
    category: "my-class-1", name: "my-transaction-name",
    url: "http://localhost",
    attributes: ["tom": "jerry", "pros":"cons", "muddy":"puddels"],
    maxTraceSegments: 2000)

Error Notice

Perfect NewRelic provides setErrorNotice() function for transactions:

try t.setErrorNotice(
    exceptionType: "my-panic-type-1",
    errorMessage: "my-notice",
    stackTrace: "my-stack",
    stackFrameDelimiter: "<frame>")

Parameters of setErrorNotice():

  • exceptionType: type of exception that occurred
  • errorMessage: error message
  • stackTrace: print stack trace when error occurred
  • stackFrameDelimiter: delimiter to split stack trace into frames


Segments in a transaction can be either Generic, DataStore or External, see demo below:

// assume t is a transaction
try t.setErrorNotice(exceptionType: "my-panic-type-1", errorMessage: "my-notice", stackTrace: "my-stack", stackFrameDelimiter: "<frame>")

let root = try t.segBeginGeneric(name: "my-segment")
// do some generic operations in this transaction
try t.segEnd(root)

// NOTE: it will automatically obfuscate the sql input and rollup if failed as well
let sub = try t.segBeginDataStore(table: "my-table", operation: .INSERT, sql: "INSERT INTO table(field) value('000-000-0000')")
// do some data operations in this transaction
try t.segEnd(sub)

let s2 = try t.segBeginExternal(host: "", name: "my-seg")
// do some external operations in this transaction
try t.segEnd(s2)


  • parentSegmentId: id of parent segment, root segment by default, i.e., NewRelic.ROOT_SEGMENT.
  • name: name to represent segment