Implement response compression for Testplugin

[mm-hsh]

This pull request adds support for HTTP response compression to improve performance and reduce bandwidth usage in the AAS.TwinEngine.Plugin.TestPlugin application. The main changes involve configuring Brotli and Gzip compression providers and enabling response compression for HTTPS traffic.

Response Compression Enhancements:

• Added and configured Brotli and Gzip response compression providers in the Program.cs startup logic, enabling compression for HTTPS responses and setting both providers to use optimal compression level.
• Enabled response compression middleware in the application pipeline to ensure compressed responses are served to clients.

[github-actions]

Dependency Review

✅ No vulnerabilities or license issues or OpenSSF Scorecard issues found.

Scanned Files

None

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[github-actions]

Test & Coverage Report

Test Results Summary

Metric	Count
✅ Passed	1019
❌ Failed	0
⏭️ Skipped	0

View Detailed Test Results

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Code Coverage

Unit Tests Coverage

Package	Line Rate	Branch Rate	Complexity	Health
AAS.TwinEngine.DataEngine	91%	83%	1504	✔
Summary	91% (2551 / 2801)	83% (1075 / 1295)	1504	✔

Minimum allowed line rate is 80%

Module Tests Coverage

Package	Line Rate	Branch Rate	Complexity	Health
AAS.TwinEngine.DataEngine	56%	42%	1504	➖
Summary	56% (1559 / 2801)	42% (540 / 1295)	1504	➖

[Copilot]

Pull request overview

Adds HTTP response compression to AAS.TwinEngine.Plugin.TestPlugin to reduce bandwidth usage and improve response performance for clients.

Changes:

• Registers Brotli and Gzip response compression providers and configures both to CompressionLevel.Optimal.
• Enables response compression for HTTPS traffic.
• Adds UseResponseCompression() to the middleware pipeline.

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[Copilot]

New code uses discard assignments (_ = ...) for service registration, but the rest of this Program.cs uses direct calls (e.g., builder.Services.AddControllers()). This inconsistency makes the startup code harder to scan and suggests two different style conventions in the same file. Consider removing the discards here (or applying the same pattern consistently throughout this file).

Suggested change

	_ = builder.Services.AddResponseCompression(options =>
	{
	options.EnableForHttps = true;
	options.Providers.Add<BrotliCompressionProvider>();
	options.Providers.Add<GzipCompressionProvider>();
	});
	_ = builder.Services.Configure<BrotliCompressionProviderOptions>(options => options.Level = CompressionLevel.Optimal);
	_ = builder.Services.Configure<GzipCompressionProviderOptions>(options => options.Level = CompressionLevel.Optimal);
	builder.Services.AddResponseCompression(options =>
	{
	options.EnableForHttps = true;
	options.Providers.Add<BrotliCompressionProvider>();
	options.Providers.Add<GzipCompressionProvider>();
	});
	builder.Services.Configure<BrotliCompressionProviderOptions>(options => options.Level = CompressionLevel.Optimal);
	builder.Services.Configure<GzipCompressionProviderOptions>(options => options.Level = CompressionLevel.Optimal);

[Copilot]

Enabling response compression for HTTPS (EnableForHttps = true) can increase exposure to BREACH-style attacks if any endpoints reflect secrets into responses while an attacker can influence part of the plaintext. Please confirm this service doesn’t return sensitive reflected content (tokens, secrets, CSRF values, etc.), or limit compression to non-sensitive content types/endpoints (and consider making this setting environment-configurable).

[Copilot]

CompressionLevel.Optimal for both Brotli and Gzip can be CPU-expensive and may increase latency under load; for APIs it’s common to use a faster level (or make the level configurable per environment). Consider switching to a faster default and/or reading the level from configuration so it can be tuned without code changes.