Add log capture methods to TestHarness for integration tests

[Copilot]

Implementation Plan for Adapter Log Capture in Integration Tests

• Explore repository structure and understand integration test framework
• Identify where adapter process is spawned (harness.ts)
• Modify adapter process spawning to capture stdout/stderr instead of inheriting
• Create log storage mechanism in TestHarness to store captured logs
• Parse captured output into structured log objects (level, timestamp, message)
• Add method getLogs() to return array of log objects
• Add method assertLog() to check for specific log messages with regex and level
• Add method clearLogs() to clear captured logs
• Export AdapterLog interface for external use
• Add tests to verify log capture functionality
• Update documentation/README with new methods and examples
• Run lint, build, and tests to ensure no regressions
• Run CodeQL security scan - no issues found
• Validate exports are working correctly
• Add changelog entry
• Ready for code review

Summary

This PR implements log capture functionality for integration tests, enabling developers to check for specific error/warning/info messages during adapter startup and execution.

Features Added

1. Log Capture: Modified TestHarness to capture stdout/stderr from the adapter process
2. Structured Log Objects: Logs are parsed into objects with level, timestamp, and message properties
3. Log Retrieval Methods:
   • getLogs(): Returns array of all captured logs
   • assertLog(pattern, level?): Checks if a log matching criteria exists
   • clearLogs(): Clears all captured logs

Implementation Details

• Changed stdio configuration from ['inherit', 'inherit', 'inherit'] to ['inherit', 'pipe', 'pipe'] to capture output
• Added log parsing to extract log level, timestamp, and message from ioBroker log format
• Logs are still output to console for visibility during test runs
• Falls back to treating unparseable lines as info-level logs
• Exported AdapterLog interface for TypeScript users

Use Case Example

suite("Check for specific error", (getHarness) => {
    let harness;
    before(() => {
        harness = getHarness();
    });

    it("Should not produce follow-up bug error", async () => {
        await harness.startAdapterAndWait();
        
        // Check that specific error doesn't appear
        const hasFollowUpBug = harness.assertLog(/follow-up-bug detected/, "error");
        expect(hasFollowUpBug).to.be.false;
    });
});

Testing & Validation

✅ All existing tests pass
✅ New unit tests added for log capture functionality
✅ Linting passes with no errors
✅ TypeScript compilation succeeds
✅ CodeQL security scan shows no vulnerabilities
✅ Exports verified to work correctly
✅ Comprehensive documentation added to README.md
✅ Changelog updated

Files Changed

• src/tests/integration/lib/harness.ts: Core implementation
• src/tests/integration/lib/harness.test.ts: Unit tests (new)
• src/tests/index.ts: Export AdapterLog type
• README.md: Documentation and examples
• CHANGELOG.md: Added entry for new feature
• build/: Compiled output

Original prompt

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This section details on the original issue you should resolve

<issue_title>[Feature request]: Method to read the log of the adapter startup in an integration test.</issue_title>
<issue_description>As a part of the integration test I would like to check for a specific error/warn/info/debug-message to be present (or not present) in the log.

I can think of two possible implementation approaches:

1. Implement a method that returns the log, e.g. as an array of log messages or log objects (logLevel, timestamp, message) or just the whole dump as string - whichever is easier to implement, though an array of log objects would be the most useful option from a developer side of view.
2. Implement a method that checks the log for containing a specific Regex with a specific log level.

Use case

During fixing a bug in my adapter I have introduced a follow-up-bug that can be identified by a specific log message. To fix this bug I would like to implement a test case that checks for this specific log message.</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes [Feature request]: Method to read the log of the adapter startup in an integration test. #627

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[Apollon77]

@copilot you missed the changelog

[Copilot]

@copilot you missed the changelog

Added changelog entry in commit 0a6e9e5.