chore: Add OSLog support for better SDK debugging/DX and redact sensitive tokens logging.

[sanchitmehta94]

• All new/changed/fixed functionality is covered by tests (or N/A)
• I have added documentation for all new/changed functionality (or N/A)

📋 Changes

Improve DX by using OSLog framework for debug loggin in Auth0 iOS SDK
https://auth0team.atlassian.net/browse/SDK-7255

https://oktawiki.atlassian.net/wiki/spaces/DXSDK/pages/2883787251/Next+major+of+Auth0.swift+Non-breaking+changes#5.-Use-OSLog-instead-of-print()-for-debug-logging

Why we should use OSLog?
The OSLog framework is Apple's modern, highly efficient, and structured logging system designed to replace older methods like print and NSLog. It significantly improves performance by having a low overhead, deferring work, and avoiding the blocking of the main thread. By using subsystems and categories, it enables developers to organize logs clearly for easy filtering in the Xcode Console app. Crucially, it provides essential privacy controls to redact sensitive data, supports various log levels (debug, error, fault) for better control over data collection, and integrates seamlessly with sysdiagnose reports for reliable debugging of production issues.

1. Debug amd Info levels logs are not persisted and for other log levels , i have kept all logs redacted when debugger is not connected in system logs. you can see them in console.app when debugger is connected not otherwise

2. have added handling to redact the sensitive info the API response being logged to Xcode console where earlier it was printing everything eg. refresh token, access token and Identity Token , now we will redact these as shown below Also made sure json is printted in pretty-printed format.

3. Also I have offloaded all network tracing computation to background thread by using a serial queue keeping main thread free (avoid freeze)

📎 References

🎯 Testing

[sanchitmehta94]

This doesn't work - OSLog needs compile-time constant
let privacy: OSLogPrivacy = isPublic ? .public : .private
so have to do this way

[NandanPrabhu]

can we use an enum in the place of a boolean. OSLogPrivacy has multiple options. So acomodating all these options will be easy using an enum https://developer.apple.com/documentation/os/oslogprivacy#Getting-the-Privacy-Options

[sanchitmehta94]

This is a fair point Nandan
however, as i mentioned above OSLog API, the privacy parameter in OSLog interpolation (e.g., (value, privacy: .public)) requires a compile-time constant from the OSLogPrivacy enum. This is a fundamental limitation of OSLog's design for security reasons. .

This does NOT work:
let privacyLevel: OSLogPrivacy = .public
logger.debug("\(value, privacy: privacyLevel)") 
 This works:
logger.debug("\(value, privacy: .public)") 

[NandanPrabhu]

makes sense. but lets plz refrain from using boolean here. a new enum imitating OSLogPrivacy with a different name should solve the purpose

[sanchitmehta94]

I’ve removed the isPublic check and kept all logs private. We don’t want to show any information when the debugger is not attached. Most of these logs are debug-only and are never persisted. Redaction only applies for string interpolation when a debugger is disconnected, and we want the full string to remain private if anything ever gets persisted. Therefore, I’m dropping support for any other visibility options for safe side we will see if we need this in future .

[NandanPrabhu]

@claude

[sanchitmehta94]

Auth0Log.debug(.configuration, "File currently has the following entries: \(String(describing: values))")
I have deliberately marked this as a debug log, because if a developer unknowingly includes sensitive tokens in the plist, it won’t pose a risk — debug logs are not persisted to disk, whereas error logs are.

[Copilot]

Pull request overview

This PR modernizes the Auth0 iOS SDK's debugging experience by migrating from print() statements to Apple's OSLog framework. The change introduces structured, categorized logging with privacy controls while maintaining backward compatibility through the existing .logging(enabled: true) API.

Key Changes

• Introduced Auth0Log unified logging system with OSLog backend supporting debug, info, warning, error, and fault levels
• Replaced all debug print() calls with Auth0Log calls using appropriate categories (NetworkTracing, Configuration)
• Added comprehensive documentation for filtering logs in Xcode 15+ console

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 8 comments.

Show a summary per file

File	Description
Auth0/Auth0Log.swift	New unified logging system with OSLog implementation, protocols, and convenience methods
Auth0Tests/LoggerSpec.swift	Comprehensive test suite for Auth0Log with mock service and test coverage for all log levels
Auth0/Logger.swift	Updated DefaultOutput to use Auth0Log instead of print()
Auth0/Request.swift	Replaced print() error statements with Auth0Log.debug()
Auth0/Auth0.swift	Replaced print() configuration error messages with Auth0Log.error() and Auth0Log.debug()
README.md	Added logging documentation section with filtering instructions and category descriptions
Auth0.xcodeproj/project.pbxproj	Added Auth0Log.swift to all build targets

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[sanchitmehta94]

removed this . These got accidently added in this PR

[sanchitmehta94]

Typo: fixing in next PR (Network Tracing based logs)