LGLogger

LGLogger helps iOS developers inspect their app's own diagnostic messages with print()-style calls, module and severity filters, optional saved logs, and a floating in-app log viewer. It is a small Swift package with no package dependencies, for iOS 17+ and Swift 5.10+.

Install · Runnable example · API reference · Questions and feedback · Contribute

Install

In Xcode, choose File → Add Package Dependencies…, enter:

https://github.com/chandanankush/LGLogger.git

Choose Up to Next Major Version from 1.0.0, add the LGLogger product to your iOS app target, then import LGLogger. Tag 1.0.0 exists; there is no packaged GitHub Release. The README on main describes current source; choose a branch deliberately if testing changes after that tag.

For another Swift package, add the dependency and target product to your existing manifest:

// In Package(...):
dependencies: [
    .package(url: "https://github.com/chandanankush/LGLogger.git", from: "1.0.0")
],
targets: [
    .target(name: "YourTarget", dependencies: [
        .product(name: "LGLogger", package: "LGLogger")
    ])
]

For local development, clone this repository and use Xcode's Add Local… package option; any folder location works. Build using an iOS destination: macOS swift build / swift test cannot compile its UIKit and MessageUI imports.

Try it in a demo app

Create a disposable SwiftUI iOS 17+ app, add the package, and replace its generated app entry point with this example. It writes only invented messages in the demo app's sandbox; it has no upload endpoint.

import SwiftUI
import LGLogger

@main
@MainActor
struct LoggingDemoApp: App {
    var body: some Scene {
        WindowGroup {
            Button("Write a demo message") {
                LGPrint("Demo", "Button tapped", level: .info)
            }
            .onAppear {
                #if DEBUG
                LGSettings.enableFileLogging(levels: [.info, .warning, .error])
                LGOverlay.install()
                #endif
            }
        }
    }
}

Run a Debug build on an iOS simulator, press the button, then tap the floating bubble to open the saved log. File logging starts off; the example opts in for Debug builds. The overlay is optional and can be installed once from your own UI lifecycle.

Everyday usage

LGPrint("hello")                                  // .debug by default
LGPrint("Auth", "Example session expired", level: .warning)
LGSettings.setLogLevel(onlyModules: ["Auth"])       // exact module matches
LGSettings.showConsole(onlyLevels: [.warning, .error])
LGSettings.enableFileLogging(levels: [.error])      // independent file severity filter
LGSettings.setLogLevelAll()                        // remove module filter
LGSettings.disableFileLogging()

An active module filter also suppresses untagged calls. .debug messages are suppressed in non-DEBUG builds regardless of filters; use an explicit .info or higher level for release diagnostics. The message expression is evaluated only when an enabled destination consumes it. See the reference for output methods, file locations, upload APIs, overlay behavior, and architecture.

Privacy and limitations

• Only explicit LGPrint messages are saved; this does not capture all process stdout/stderr. Avoid logging tokens, passwords, personal data, or private payloads. File logging has no built-in size limit or retention policy.
• Email and HTTP actions process all saved log files. Successful sends/uploads delete those files. A partly failed HTTP batch can already have deleted successful files; failures do not roll them back. Review logs before sharing them.
• HTTP upload is one plain-text POST per file, with no authentication-header API, multipart support, or retry. Mail attachments are loaded into memory. No endpoint is configured by default; Upload appears only after you supply LGSettings.uploadURL.
• A file-open failure disables further file writes for that process launch. Relaunching is needed to try again.
• The overlay's position is not saved across launches, and its drag bounds are not recalculated on rotation or iPad window resize. Device compatibility feedback is welcome.
• The package currently has one iOS-only target. The existing simulator tests cover routing, file-sink behavior, clamping, and helpers; network POST/delete behavior and full UI interactions are not covered by those unit tests.

Support and contribution

Use Discussions for integration questions and feedback. Report reproducible problems in Issues with your iOS version, Xcode version, package tag/commit, and a minimal demo using invented data. Start with CONTRIBUTING for safe simulator validation and scoped tasks.

This repository currently contains no license file. Public source availability alone does not grant reuse or redistribution rights; ask the maintainer about licensing before adopting it in a distributed app.