sentinel-api 1.0.3

Intelligent API Gateway with rate limiting and anomaly detection

SentinelAPI

SentinelAPI is an intelligent API gateway that provides JWT auth, per-user rate limiting, structured request telemetry, and scheduled anomaly detection with auto-blocking.

Why no Amazon Lookout for Metrics?

We intentionally do not implement Lookout for Metrics because it is not practical for free-tier testing in this project. Instead, anomaly detection is implemented with a scheduled Lambda on DynamoDB aggregates, with SNS alerting and optional auto-blocking.

Architecture

SentinelAPI uses one cloud-native architecture:

• ECS Fargate service behind an ALB
• ElastiCache Redis for token-bucket rate limiting
• DynamoDB for request logs, aggregates, and blocklist state
• EventBridge schedule -> Lambda anomaly detector -> SNS alerts
• Fargate tasks in public subnets, no NAT gateway

Optimization Presets

SentinelAPI supports optional optimization presets in code:

• cost (default)
• performance

Set with:

SENTINEL_API_OPTIMIZE_FOR=cost
# or
SENTINEL_API_OPTIMIZE_FOR=performance

Preset values are defaults only. Any explicitly provided knob in shell env or .env overrides the preset.

Environment File

.env is optional. SentinelAPI SDK deploy reads:

1. System environment variables
2. .env in repo root (if present)

Required:

• SENTINEL_API_UPSTREAM_BASE_URL
• at least one auth method:
  • SENTINEL_API_JWT_SECRET_KEY (HS*)
  • SENTINEL_API_JWT_PUBLIC_KEY (static public key)
  • SENTINEL_API_JWT_JWKS_URL (OIDC/JWKS)

Optional:

• SENTINEL_API_OPTIMIZE_FOR
• explicit knob overrides (Fargate sizing, desired count, rate/anomaly knobs, timeouts, JWT algorithm)

Precedence:

1. Explicit shell/CI env vars
2. .env (if present)
3. Built-in preset defaults (cost or performance)

One-Command AWS Deploy (SDK Full Stack)

./deploy.sh

One-Command AWS Teardown

./teardown.sh

Requirements:

• AWS credentials configured locally
• Docker installed and running (used to build and push gateway image)

Before deploy, set SENTINEL_API_UPSTREAM_BASE_URL in .env to the backend you want SentinelAPI to protect. You can set it either in your shell/CI environment or in .env.

For the example Lambda backend, use the Function URL printed by:

./examples/example-api/scripts/deploy.sh

JWT Configuration

SentinelAPI does not auto-generate JWT verification keys. You must provide auth settings via shell env or .env before deploy.

At least one is required:

• SENTINEL_API_JWT_SECRET_KEY for HS* verification
• SENTINEL_API_JWT_PUBLIC_KEY for static RS*/ES* public-key verification
• SENTINEL_API_JWT_JWKS_URL for JWKS-based verification (recommended)

Local Testing and Linting

./scripts/test.sh
make lint

Makefile Shortcuts

make lint
make test
make deploy
make teardown

CI/CD (GitHub Actions + OIDC)

Workflow file: .github/workflows/deploy.yml

On push to main:

1. lint job runs ruff
2. test job runs pytest
3. validate_templates job runs SDK dry-run plan
4. deploy job calls reusable integration workflow (.github/workflows/integration-tests.yml), deploys SentinelSdkFull, runs smoke checks, then always tears down Sentinel + example-api stacks

Required secret:

• AWS_DEPLOY_ROLE_ARN
• SENTINEL_API_UPSTREAM_BASE_URL
• SENTINEL_API_JWT_SECRET_KEY

PyPI Release Pipeline

Workflow file: .github/workflows/release.yml

Trigger:

• push a tag like v0.1.1
• or run workflow manually from Actions tab

Pipeline stages:

1. lint + tests
2. build wheel/sdist + twine check
3. reusable integration tests (.github/workflows/integration-tests.yml)
4. publish to PyPI

Tag and push release:

git tag v0.1.1
git push origin v0.1.1

Required one-time setup:

1. Create project on PyPI (name: sentinel-api) or reserve the name.
2. In GitHub repo settings, add environment pypi.
3. In PyPI project settings, add a trusted publisher:
   • Owner: SamioneX
   • Repository: SentinelAPI
   • Workflow: release.yml
   • Environment: pypi

Runtime Backends

SentinelAPI runtime uses fixed backends:

• rate limiting: Redis
• request logging: DynamoDB

JWT Verification Modes

• Shared-secret/static-key mode:
  • SENTINEL_API_JWT_SECRET_KEY (HS256) or SENTINEL_API_JWT_PUBLIC_KEY
• JWKS discovery mode:
  • SENTINEL_API_JWT_JWKS_URL
  • SENTINEL_API_JWT_JWKS_CACHE_TTL_SECONDS

When SENTINEL_API_JWT_JWKS_URL is set, JWKS key selection by token kid is used.

JWT Testing Quickstart

python3 scripts/generate_jwt.py --env-file .env --user-id demo-user

TOKEN="$(python3 scripts/generate_jwt.py --env-file .env --user-id demo-user)"
curl -X GET "http://localhost:8000/auth/verify" \
  -H "Authorization: Bearer ${TOKEN}"

curl -X GET "http://localhost:8000/proxy/v1/orders?limit=5" \
  -H "Authorization: Bearer ${TOKEN}"

Anomaly Detection Smoke Test

You can validate the anomaly pipeline end-to-end without waiting for the 15-minute schedule.

Requirements:

• Sentinel stack deployed
• example upstream reachable
• JWT secret available in env:
  • SMOKE_JWT_SECRET_KEY (preferred), or
  • SENTINEL_API_JWT_SECRET_KEY

Run:

python3 scripts/anomaly_smoke.py --stack-name SentinelSdkFull --region us-east-1

What it does:

• seeds baseline traffic into aggregate buckets
• sends a burst of authenticated requests through the ALB
• invokes the anomaly Lambda directly
• checks that the user appears in the blocklist table

If needed, tune sensitivity in the command:

python3 scripts/anomaly_smoke.py \
  --stack-name SentinelSdkFull \
  --region us-east-1 \
  --baseline-hourly 10 \
  --burst-requests 120

Core Components

• API app: src/sentinel_api/main.py
• Auth: src/sentinel_api/services/auth.py
• Rate limiting: src/sentinel_api/services/rate_limiter.py
• Request logging: src/sentinel_api/services/request_logger.py
• Anomaly Lambda: lambda/anomaly_detector/handler.py
• SDK deploy library: src/sentinel_api/sdk_deployer.py
• SDK templates: infrastructure/templates/foundation.yaml, infrastructure/templates/full.yaml

Example Backend

Use examples/example-api as an upstream target:

• deploy: ./examples/example-api/scripts/deploy.sh
• destroy: ./examples/example-api/scripts/destroy.sh

InfraKit + SDK Strategy

SentinelAPI uses an SDK-native deploy model designed to align with InfraKit's lean approach and avoid CDK runtime dependency.

• migration docs: infrastructure/README.md
• parity tracker: infrastructure/PARITY_CHECKLIST.md
• full stack deploy: ./deploy.sh
• full stack teardown: ./teardown.sh
• foundation deploy: python3 infrastructure/deploy.py --stack-name SentinelSdkFoundation --region us-east-1
• foundation teardown: python3 infrastructure/teardown.py --stack-name SentinelSdkFoundation --region us-east-1

Importable API (for InfraKit/provider integration):

• from sentinel_api import deploy_foundation, deploy_full, teardown_foundation

Adoption Docs and Templates

• Product-style onboarding: USAGE.md
• Proposed InfraKit custom resource contract: infrakit/resource-spec.md
• InfraKit templates:
  • infrakit/templates/sentinelapi-minimal.yaml
  • infrakit/templates/sentinelapi-production.yaml