AvdLee/Diagnostics

Example mail composer	Example Report

Diagnostics is a library written in Swift which makes it really easy to share Diagnostics Reports to your support team.

• Features
• Requirements
• Usage
  • Agent-friendly reports
  • Install the Agent Skill
  • Using a custom UserDefaults type
  • Filtering out sensitive data
  • Adding your own custom logs
  • Adding your own custom report
  • Smart insights
• Communication
• Installation
• Release Notes
• License

Features

The library allows to easily attach the Diagnostics Report as an attachment to the MFMailComposeViewController.

• [x] Integrated with the MFMailComposeViewController
• [x] Default reporters include:
  • App metadata
  • System metadata
  • System logs divided per session
• [x] Possibility to filter out sensitive data using a DiagnosticsReportFilter
• [x] A custom DiagnosticsLogger to add your own logs
• [x] Agent-friendly single-file HTML reports with embedded structured JSON or standalone JSON output
• [x] Smart insights like "⚠️ User is low on storage" and "✅ User is using the latest app version"
• [x] Flexible setup to add your own smart insights
• [x] Flexible setup to add your own custom diagnostics
• [x] Native cross-platform support, e.g. iOS, iPadOS and macOS

Usage

The default report already contains a lot of valuable information and could be enough to get you going.

Make sure to set up the DiagnosticsLogger as early as possible to catch all the system logs, for example in the didLaunchWithOptions:

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
    do {
        try DiagnosticsLogger.setup()
    } catch {
        print("Failed to setup the Diagnostics Logger")
    }
    return true
}

Then, simply show the MFMailComposeViewController using the following code:

import UIKit
import MessageUI
import Diagnostics

class ViewController: UIViewController {

    @IBAction func sendDiagnostics(_ sender: UIButton) {
        Task { @MainActor in
            /// Create the report.
            let report = await DiagnosticsReporter.create()

            guard MFMailComposeViewController.canSendMail() else {
                /// For debugging purposes you can save the report to desktop when testing on the simulator.
                /// This allows you to iterate fast on your report.
                report.saveToDesktop()
                return
            }

            let mail = MFMailComposeViewController()
            mail.mailComposeDelegate = self
            mail.setToRecipients(["support@yourcompany.com"])
            mail.setSubject("Diagnostics Report")
            mail.setMessageBody("An issue in the app is making me crazy, help!", isHTML: false)

            /// Add the Diagnostics Report as an attachment.
            mail.addDiagnosticReport(report)

            present(mail, animated: true)
        }

    }

}

extension ViewController: MFMailComposeViewControllerDelegate {
    func mailComposeController(_ controller: MFMailComposeViewController, didFinishWith result: MFMailComposeResult, error: Error?) {
        controller.dismiss(animated: true)
    }
}

On macOS you could send the report by using the NSSharingService:

import AppKit
import Diagnostics

func send(report: DiagnosticsReport) {
    let service = NSSharingService(named: NSSharingService.Name.composeEmail)!
    service.recipients = ["support@yourcompany.com"]
    service.subject = "Diagnostics Report"

    let url = URL(fileURLWithPath: NSTemporaryDirectory()).appendingPathComponent("Diagnostics-Report.html")

    // remove previous report
    try? FileManager.default.removeItem(at: url)

    do {
        try report.data.write(to: url)
    } catch {
        print("Failed with error: \(error)")
    }

    service.perform(withItems: [url])
}

Agent-friendly reports

Diagnostics reports remain a single .html attachment that users can email and open in a browser. New reports also embed a structured JSON payload in:

<script id="diagnostics-report-data" type="application/json">

Support agents and AI tools should parse that JSON first instead of loading the rendered HTML. The payload contains report metadata, agent hints, structured chapters, session metadata, and log events with levels like debug, system, error, and crash.

The browser view is generated from this JSON. Chapters can still include legacyHTML when custom formatting is needed, and older on-device log sessions remain readable after users update to a newer Diagnostics version. This repository also includes a reusable analyzer skill in diagnostics-report-analyzer-skill for clients that support agent skills/plugins.

If your support workflow consumes JSON directly, create a standalone JSON report instead:

let report = await DiagnosticsReporter.create(format: .json)

Install the Agent Skill

For the easiest setup, install the analyzer skill with npx skills:

npx skills add https://github.com/AvdLee/Diagnostics --skill diagnostics-report-analyzer-skill

See agent-skill-install-instructions.md for Claude, Cursor, OpenAI-compatible tools, pi, and manual installation options.

Using a UserDefaultsReporter

In order to use UserDefaultsReporter, you need to specify the desired UserDefaults instance together with all the keys you would like to read, and use it in DiagnosticsReporter.create(filename:using:filters:smartInsightsProvider) to create a DiagnosticsReport.

let userDefaultsReporter = UserDefaultsReporter(
    userDefaults: UserDefaults(suiteName: "a.userdefaults.instance"),
    keys: ["key_1"]
)

let diagnosticsReport = await DiagnosticsReporter.create(using: [userDefaultsReporter])

Filtering out sensitive data

It could be that your report is containing sensitive data. You can filter this out by creating a DiagnosticsReportFilter.

The example project contains an example of this:

struct DiagnosticsDictionaryFilter: DiagnosticsReportFilter {

    // This demonstrates how a filter can be used to filter out sensible data.
    static func filter(_ diagnostics: Diagnostics) -> Diagnostics {
        guard let dictionary = diagnostics as? [String: String] else { return diagnostics }
        return dictionary.filter { keyValue -> Bool in
            if keyValue.key == "App Display Name" {
                // Filter out the key with the value "App Display Name"
                return false
            } else if keyValue.key == "AppleLanguages" {
                // Filter out a user defaults key.
                return false
            }
            return true
        }
    }
}

Which can be used by passing in the filter into the create(..) method:

let report = await DiagnosticsReporter.create(using: reporters, filters: [DiagnosticsDictionaryFilter.self])

Adding your own custom logs

To make your own logs appear in the logs diagnostics you need to make use of the DiagnosticsLogger.

/// Support logging simple `String` messages.
DiagnosticsLogger.log(message: "Application started")

/// Support logging `Error` types.
DiagnosticsLogger.log(error: ExampleError.missingData)

The error logger will make use of the localized description if available which you can add by making your error conform to LocalizedError.

Adding a directory tree report

It's possible to add a directory tree report for a given set of URL, resulting in the following output:

└── Documents
    +-- contents
    |   +-- B3F2F9AD-AB8D-4825-8369-181DEAAFF940.png
    |   +-- 5B9C090E-6CE1-4A2F-956B-15897AB4B0A1.png
    |   +-- 739416EF-8FF8-4502-9B36-CEB778385BBF.png
    |   +-- 27A3C96B-1813-4553-A6B7-436E6F3DBB20.png
    |   +-- 8F176CEE-B28F-49EB-8802-CC0438879FBE.png
    |   +-- 340C2371-A81A-4188-8E04-BC19E94F9DAE.png
    |   +-- E63AFEBC-B7E7-46D3-BC92-E34A53C0CE0A.png
    |   +-- 6B363F44-AB69-4A60-957E-710494381739.png
    |   +-- 9D31CA40-D152-45D9-BDCE-9BB09CCB825E.png
    |   +-- 304E2E41-9697-4F9A-9EE0-8D487ED60C45.jpeg
    |   └── 7 more file(s)
    +-- diagnostics_log.txt
    +-- Okapi.sqlite
    +-- Library
    |   +-- Preferences
    |   |   └── group.com.swiftlee.app.plist
    |   └── Caches
    |       └── com.apple.nsurlsessiond
    |           └── Downloads
    |               └── com.swiftlee
    +-- Coyote.sqlite-shm
    +-- Coyote.sqlite
    +-- Coyote.sqlite-wal
    +-- Okapi.sqlite-shm
    +-- Okapi.sqlite-wal
    └── 1 more file(s)

You can do this by adding the DirectoryTreesReporter:

var reporters = DiagnosticsReporter.DefaultReporter.allReporters
let documentsURL = try! FileManager.default.url(for: .documentDirectory, in: .userDomainMask, appropriateFor: nil, create: false)
let directoryTreesReporter = DirectoryTreesReporter(
    directories: [
        documentsURL
    ]
)
reporters.insert(directoryTreesReporter, at: 1)

Adding your own custom report

To add your own report you need to make use of the DiagnosticsReporting protocol.

/// An example Custom Reporter.
struct CustomReporter: DiagnosticsReporting {
    static func report() -> DiagnosticsChapter {
        let diagnostics: [String: String] = [
            "Logged In": Session.isLoggedIn.description
        ]

        return DiagnosticsChapter(title: "My custom report", diagnostics: diagnostics)
    }
}

You can then add this report to the creation method:

var reporters = DiagnosticsReporter.DefaultReporter.allReporters
reporters.insert(CustomReporter.self, at: 1)
let report = await DiagnosticsReporter.create(using: reporters)

Smart Insights

By default, standard Smart Insights are provided:

• UpdateAvailableInsight uses your bundle identifier to fetch the latest available app version. An insight will be shown whether an update is available to the user or not.
• DeviceStorageInsight shows whether the user is out of storage or not

Adding your own custom insights

It's possible to provide your own custom insights based on the chapters in the report. A common example is to parse the errors and show a smart insight about an occurred error:

struct SmartInsightsProvider: SmartInsightsProviding {
    func smartInsights(for chapter: DiagnosticsChapter) -> [SmartInsightProviding] {
        guard let html = chapter.diagnostics as? HTML else { return [] }
        if html.errorLogs.contains(where: { $0.contains("AppDelegate.ExampleLocalizedError") }) {
            return [
                SmartInsight(
                    name: "Localized data",
                    result: .warn(message: "An error was found regarding missing localisation.")
                )
            ]
        }
        return []
    }
}

The example project provides the above sample code for you to try out. You can make use of html.errorLogs, .debugLogs, and .systemLogs to quickly access specific logs from the report.

Creating a custom HTML formatter for your report

You can make use of the HTMLFormatting protocol to customize the way the HTML is reported.

Simply pass in the formatter into the DiagnosticsChapter initialiser:

DiagnosticsChapter(title: "UserDefaults", diagnostics: userDefaults, formatter: <#HTMLFormatting.Type#>)

Communication

• If you found a bug, open an issue.
• If you have a feature request, open an issue.
• If you want to contribute, submit a pull request.

Installation

Swift Package Manager

The Swift Package Manager is a tool for managing the distribution of Swift code. It’s integrated with the Swift build system to automate the process of downloading, compiling, and linking dependencies.

Manifest File

Add Diagnostics as a package to your Package.swift file and then specify it as a dependency of the Target in which you wish to use it.

import PackageDescription

let package = Package(
    name: "MyProject",
    platforms: [
       .macOS(.v10_15)
    ],
    dependencies: [
        .package(url: "https://github.com/AvdLee/Diagnostics.git", .upToNextMajor(from: "6.0.0"))
    ],
    targets: [
        .target(
            name: "MyProject",
            dependencies: ["Diagnostics"]),
        .testTarget(
            name: "MyProjectTests",
            dependencies: ["MyProject"]),
    ]
)

Xcode

To add Diagnostics as a dependency to your Xcode project, select File > Swift Packages > Add Package Dependency and enter the repository URL: https://github.com/AvdLee/Diagnostics.git.

Carthage

Carthage is a decentralized dependency manager that builds your dependencies and provides you with binary frameworks.

You can install Carthage with Homebrew using the following command:

$ brew update
$ brew install carthage

To integrate Diagnostics into your Xcode project using Carthage, specify it in your Cartfile:

github "AvdLee/Diagnostics" ~> 6.00

Run carthage update to build the framework and drag the built Diagnostics.framework into your Xcode project.

Manually

If you prefer not to use any of the aforementioned dependency managers, you can integrate Diagnostics into your project manually.

Embedded Framework

• Open up Terminal, cd into your top-level project directory, and run the following command "if" your project is not initialized as a git repository:

  $ git init

• Add Diagnostics as a git submodule by running the following command:

  $ git submodule add https://github.com/AvdLee/Diagnostics.git

• Open the new Diagnostics folder, and drag the Diagnostics folder into the Project Navigator of your application's Xcode project. This will add the SPM package as a local package.

  It should appear nested underneath your application's blue project icon. Whether it is above or below