EE and Streaming licensing

[buger]

User description

Description

Add licensing mechanism for the EE gateway, and require "streams" claim for the Streams specifically

Similar to Dashboard, license_key, and TYK_GW_LICENSEKEY should be set.

Motivation and Context

How This Has Been Tested

Screenshots (if appropriate)

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Refactoring or add test (improvements in base code or adds test coverage to functionality)

Checklist

• I ensured that the documentation is up to date
• I explained why this PR updates go.mod in detail with reasoning why it's required
• I would like a code coverage CI quality gate exception and have explained why

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PR Type

Enhancement, Tests

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Description

• Added a new licensing mechanism for the EE gateway, including a LicenseKey field in the configuration.
• Implemented a new package for handling and validating licenses, with support for test mode.
• Integrated license feature checks in the streaming middleware to ensure the "streams" feature is enabled.
• Added comprehensive tests for the new license handling functionality, covering various scenarios.
• Integrated license validation in the server startup process, logging errors if validation fails.

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Changes walkthrough 📝

	Relevant files
Enhancement	config.go Add LicenseKey field to Config struct                                        config/config.go Added LicenseKey field to Config struct. +1/-0      license.go Implement license handling and validation package                ee/license/license.go Introduced a new package for handling licenses. Implemented functions for loading and validating licenses. Added support for test mode in license handling. +191/-0  middleware.go Integrate license feature check in streaming middleware    ee/middleware/streams/middleware.go Integrated license feature check for streaming. Added logging for license validation in streaming middleware. +6/-0      license_check.go Add placeholder license check for non-EE builds                    gateway/license_check.go Added a placeholder function for license checking in non-EE builds. +9/-0      license_check_ee.go Implement license validation for EE builds                              gateway/license_check_ee.go Implemented license validation for EE builds. Logged errors if license validation fails. +18/-0    server.go Integrate license check in server startup                                gateway/server.go Integrated license check during server startup. Logged fatal error if license check fails. +4/-0
Tests	license_test.go Add tests for license handling and validation                        ee/license/license_test.go Added tests for license handling and validation. Covered scenarios for test mode, feature checks, and invalid licenses. +266/-0  mw_streaming_test.go Add license feature setup in streaming tests                          gateway/mw_streaming_test.go Added setup and cleanup for streaming tests with license features. Ensured streaming tests check for license features. +39/-0

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[github-actions]

PR Reviewer Guide 🔍

Here are some key observations to aid the review process:

⏱️ Estimated effort to review: 4 🔵🔵🔵🔵⚪

🧪 PR contains tests

🔒 No security concerns identified

⚡ Recommended focus areas for review Error Handling The error messages in the licensing module could be more descriptive to aid in debugging and user guidance. Consider adding more context or suggestions for resolution. Feature Check The check for the 'streams' feature in the license should be accompanied by a more user-friendly error or warning message, potentially guiding the user on how to enable this feature if it's not present.

[github-actions]

PR Code Suggestions ✨

Explore these optional code suggestions:

Category	Suggestion	Score
Possible bug	Ensure the expiration timestamp is valid to prevent runtime errors Add a check to ensure that the exp claim is a valid timestamp before converting it to int64 to prevent potential runtime panics. ee/license/license.go [129-135] -if exp, ok := claims["exp"].(float64); ok { +if exp, ok := claims["exp"].(float64); ok && exp > 0 { if int64(exp) < time.Now().Unix() { return errors.New("license has expired") } } else { return errors.New("exp claim is missing or invalid") } Suggestion importance[1-10]: 8 Why: This suggestion adds a check to ensure the exp claim is a valid timestamp before conversion, which helps prevent potential runtime panics. It addresses a possible bug and improves the robustness of the code.	8
Enhancement	Improve memory management and behavior consistency when enabling test mode Consider handling the case where lic is not nil when enabling test mode to avoid potential memory leaks or unexpected behavior. ee/license/license.go [43-50] testMode = true -if lic == nil { +if lic != nil { + lic.Scopes = make(map[string]bool) +} else { lic = &License{ Scopes: make(map[string]bool), } } Suggestion importance[1-10]: 7 Why: The suggestion addresses a potential issue where the lic variable might not be nil when enabling test mode, which could lead to unexpected behavior. By resetting the scopes if lic is not nil, the suggestion enhances memory management and ensures consistent behavior.	7
Maintainability	Refactor the Load function to improve code organization and maintainability Refactor the Load function to separate concerns, improving readability and maintainability by breaking down the function into smaller, more focused sub-functions. ee/license/license.go [82-162] func Load(licenseString string) error { ... if testMode { - ... + return handleTestMode(licenseString) } + return handleProductionMode(licenseString) +} +func handleTestMode(licenseString string) error { ... - if PublicKeyPEM == "" { - ... - } - ... - if err != nil { - ... - } +} +func handleProductionMode(licenseString string) error { ... } Suggestion importance[1-10]: 6 Why: The suggestion proposes refactoring the Load function to separate concerns, which can enhance readability and maintainability. While it doesn't address a critical issue, it provides a moderate improvement in code organization.	6
Best practice	Add a reset function to ensure clean state management Implement a cleanup function to reset the lic and testMode variables to their default states to ensure clean state management between tests or mode switches. ee/license/license.go [54-59] -func DisableTestMode() { +func ResetLicenseState() { licMutex.Lock() defer licMutex.Unlock() testMode = false lic = nil } +func DisableTestMode() { + ResetLicenseState() +} Suggestion importance[1-10]: 5 Why: Implementing a cleanup function for resetting lic and testMode variables can improve state management between tests or mode switches. This suggestion follows best practices for clean state management, though it is not critical.	5