[Pouyanpi]

Description

Add bounded YAML loading and server-owned validate, inspect, schema and serve commands. Include a local Rails example and offline socket tests; reuse the typed configuration and existing lifespan.

Stack: #2466 → #2467 → #2468. Package separation follows separately; API-docs prototype excluded.

PR	Base
#2467: typed composition	#2466
#2468: YAML/launcher	#2467

Summary by CodeRabbit

• New Features

  • Added an experimental YAML-configured proxy launcher.
  • Added commands to validate, inspect, generate schemas, and serve proxy manifests.
  • Added support for Chat Completions and Responses operations with configurable providers.
  • Added manifest validation with clear diagnostics and safe configuration handling.
  • Added example proxy and Rails configurations with input and output content checks.

• Documentation

  • Documented installation, manifest configuration, CLI usage, security settings, streaming behavior, and troubleshooting.

• Tests

  • Expanded coverage for validation, streaming, blocked content, disconnect handling, and launcher lifecycle.

[codecov]

Codecov Report

❌ Patch coverage is 96.75325% with 5 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
nemoguardrails/server/experimental/__main__.py	0.00%	3 Missing ⚠️
...rails/server/experimental/_application_manifest.py	99.00%	1 Missing ⚠️
nemoguardrails/server/experimental/cli.py	98.00%	1 Missing ⚠️

📢 Thoughts on this report? Let us know!

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

• Configuration used: Repository: NVIDIA-NeMo/Guardrails/.coderabbit.yaml
• Review profile: CHILL
• Plan: Enterprise
• Run ID: 570c0721-8043-4b63-b2c1-9f6ef53b9bee

📥 Commits

Reviewing files that changed from the base of the PR and between bf9dc0a and c7c2f0f.

📒 Files selected for processing: 9

• nemoguardrails/server/experimental/__main__.py
• nemoguardrails/server/experimental/_application_manifest.py
• nemoguardrails/server/experimental/application.md
• nemoguardrails/server/experimental/cli.py
• nemoguardrails/server/experimental/examples/basic/proxy.yaml
• nemoguardrails/server/experimental/examples/basic/rails/config.yml
• tests/server/experimental/test_application_manifest.py
• tests/server/experimental/test_proxy_launcher.py
• tests/server/experimental/test_streaming_http.py

Included review availability: This review used your included allowance. Your plan provides up to 12 included reviews per hour; 10 remain after this review.

📝 Walkthrough

The experimental server now loads bounded YAML manifests and provides commands to validate, inspect, generate a schema for, and serve proxy applications. The change also adds a basic policy example, launcher integration tests, documentation, and a conditional timeout in a streaming cleanup test.

Changes: Proxy manifest launcher

Layer / File(s)	Summary
Manifest schema and bounded loading nemoguardrails/server/experimental/_application_manifest.py, tests/server/experimental/test_application_manifest.py	The loader validates manifest declarations, rejects unsupported YAML constructs, enforces input limits, and resolves Rails configuration paths relative to the manifest. Tests cover parsing, validation, and sanitized errors.
CLI preparation and application commands nemoguardrails/server/experimental/cli.py, nemoguardrails/server/experimental/__main__.py, nemoguardrails/server/experimental/application.md, tests/server/experimental/test_application_manifest.py	The CLI adds validate, inspect, schema, and serve commands. Tests cover assembly, inspection, schema output, command usage, and startup rollback. The documentation describes command behavior and configuration constraints.
Example policy and proxy integration nemoguardrails/server/experimental/examples/basic/*, nemoguardrails/server/experimental/application.md, tests/server/experimental/test_proxy_launcher.py	The example configures a local OpenAI provider and email checks for input and output. Documentation and integration tests cover Chat Completions and Responses, buffered and streaming checks, and disconnect handling.

Streaming cleanup timeout test

Layer / File(s)	Summary
Conditional cleanup timeout tests/server/experimental/test_streaming_http.py	The test uses a 0.1-second cleanup timeout when cleanup hangs and a 0.01-second timeout in other modes.

Priority: ⬇️ Low

Estimated code review effort: 4 (Complex) | ~45 minutes

Change: Feature

Sequence Diagram(s)

sequenceDiagram
  actor Operator
  participant TyperCLI
  participant Prepare as _prepare
  participant ManifestLoader as load_manifest
  participant FastAPIAssembly as FastAPI application assembly
  participant Uvicorn
  Operator->>TyperCLI: run serve with manifest
  TyperCLI->>Prepare: prepare application
  Prepare->>ManifestLoader: load manifest path
  ManifestLoader-->>Prepare: return ProxyConfig
  Prepare->>FastAPIAssembly: assemble application
  FastAPIAssembly-->>Prepare: return FastAPI application
  Prepare-->>TyperCLI: return config and application
  TyperCLI->>Uvicorn: run application with host and port

Loading

Merge Risk: ⚪ Minimal · up to c7c2f

No actionable merge-blocking issue remains in the reviewed launcher changes.

Pre-merge checks: 5 · 1

Failed checks: 1 warning

Check name	Status	Explanation	Resolution
Docstring Coverage		Docstring coverage is 38.64% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 44 functions across 6 files. (3 skipped: …	Write docstrings for the functions missing them to satisfy the coverage threshold.

Passed checks: 5 passed

Check name	Status	Explanation
Description Check		Check skipped - CodeRabbit’s high-level summary is enabled.
Title check		The title clearly and concisely describes the main change: launching proxy applications from YAML manifests.
Linked Issues check		Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check		Check skipped because no linked issues were found for this pull request.
Test Results For Major Changes		The PR is a major feature change, and its description includes testing information: it states that the change includes offline socket tests. The supplied validation summary also reports 98 launcher an…

Full details: Test Results For Major Changes

Explanation

The PR is a major feature change, and its description includes testing information: it states that the change includes offline socket tests. The supplied validation summary also reports 98 launcher and streaming HTTP tests on Python 3.10 and 3.13, plus passing pre-commit checks.

Full details: Docstring Coverage

Explanation

Docstring coverage is 38.64% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 44 functions across 6 files. (3 skipped: 3 unsupported.)

Resolution

Write docstrings for the functions missing them to satisfy the coverage threshold.

✨ Finishing Touches: 💡 1

📝 Generate docstrings: 💡

• Commit to this branch
• Create a new PR

🧪 Generate unit tests (beta)

• Commit to this branch
• Create a new PR

• Autofix · Keep fixing CodeRabbit findings and required CI, and resolving merge conflicts

_{Comment @coderabbitai help to get the list of available commands.}

[greptile-apps]

Confidence Score: 5/5

[Medium impact] The PR appears safe to merge; no outstanding findings remain.

Summary

Adds a YAML launcher for proxy applications.

• Proxy manifests load as bounded, fixed-selection configuration.
• Operators can inspect and run a proxy from a YAML manifest.
• The streaming test adjusts its timeout only for hanging closes.

The previous documentation finding is fixed. No new actionable issues were found. Runtime tests were not run.

Diagram

%%{init: {'theme': 'neutral'}}%%
flowchart TD
  A[YAML manifest] --> B[Bounded loader]
  B --> C[Typed configuration]
  C --> D[Application assembly]
  D --> E[validate]
  D --> F[inspect]
  D --> G[serve]
  G --> H[Existing application lifespan]
  H --> I[Load trusted Rails and start HTTP owners]
  J[Manifest model] --> K[schema]

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_{Reviews (4) · Last reviewed commit: "fix(server): retain resolver deadlines t..." · Reviewed by Greptile}

[greptile-apps]

Validation promises too much

validate only checks that each Rails directory exists, not that config files are available. The new tests explicitly accept an empty directory. Remove “config-file availability” from this description so operators do not rely on a guarantee the command does not provide.

Suggested change

	`validate` checks the declaration, directory/config-file availability, upstream
	URL rules and route composition. It does not read Rails contents, import their
	actions, start engines, contact providers or prove checker compatibility.
	`validate` checks the declaration, directory availability, upstream URL rules
	and route composition. It does not check config-file availability, read Rails
	contents, import their actions, start engines, contact providers or prove checker
	compatibility.

Prompt To Fix With AI

This is a comment left during a code review.
Path: nemoguardrails/server/experimental/application.md
Line: 77-79

Comment:
**Validation promises too much**

`validate` only checks that each Rails directory exists, not that config files are available. The new tests explicitly accept an empty directory. Remove “config-file availability” from this description so operators do not rely on a guarantee the command does not provide.

```suggestion
`validate` checks the declaration, directory availability, upstream URL rules
and route composition. It does not check config-file availability, read Rails
contents, import their actions, start engines, contact providers or prove checker
compatibility.
```

---

For each issue above, determine whether it is valid and should be fixed. If so, fix it directly.

Note: If this suggestion doesn't match your team's coding style, reply to this and let me know. I'll remember it for next time!