Sentinel Core CI -- Microservice Pipeline Templates

A centralized Sentinel Core CI library that standardizes CI/CD workflows across application teams. Complex pipeline logic is abstracted into a single declarative wrapper, paired with Python-based pre-flight and post-deploy validation to ensure environment integrity and deployment health.

---

Repository Structure

sentinel-core-ci/
├── vars/
│   ├── standardMicroservicePipeline.groovy   # Main pipeline wrapper
│   ├── buildApp.groovy                       # Build stage
│   ├── testApp.groovy                        # Test stage
│   ├── buildAndPushContainer.groovy          # Container build & push
│   └── deployApp.groovy                      # Deployment stage
├── resources/
│   └── scripts/
│       ├── validate_env.py                   # Pre-flight env validation
│       └── verify_deploy.py                  # Post-deploy verification
├── tests/
│   ├── test_validate_env.py                  # Pre-flight tests (11 tests)
│   └── test_verify_deploy.py                 # Post-deploy tests (18 tests)
├── examples/
│   ├── Jenkinsfile                           # Optimized consumer (<20 lines)
│   └── Jenkinsfile.traditional               # Traditional comparison (304 lines)
├── src/                                      # Reserved for future use
└── README.md

---

Quick Start

1. Register the Library in Jenkins

Go to Manage Jenkins → System → Global Pipeline Libraries and add:

Field	Value
Name	sentinel-core-ci
Default Version	main
Retrieval	Modern SCM → Git
Project URL	https://github.com/<org>/sentinel-core-ci

2. Create a Consumer Jenkinsfile

In the root of your application repository, create a Jenkinsfile:

@Library('sentinel-core-ci') _

standardMicroservicePipeline(
    appName:        'order-service',
    appPort:         8080,
    deployEnv:      'staging',
    dockerRegistry: 'registry.example.com',
)

That's it. 7 lines of effective code instead of 200+. See examples/Jenkinsfile.traditional for the full comparison.

---

Configuration Reference

Required Parameters

Parameter	Type	Description
appName	String	Name of the application / service
appPort	int	Port the application listens on
deployEnv	String	Target environment (staging, production)
dockerRegistry	String	Container registry URL

Optional Parameters

Parameter	Type	Default	Description
buildCmd	String	./gradlew clean build	Shell command for the build step
testCmd	String	./gradlew test	Shell command for the test step
dockerfilePath	String	Dockerfile	Path to the Dockerfile
imageName	String	<registry>/<appName>	Full image name override
imageTag	String	${BUILD_NUMBER} or latest	Image tag override
deployTarget	String	<appName>-<deployEnv>	Container/service name on the host
deployCmd	String	(SSH + docker run)	Fully custom deploy command

---

Pre-flight Validation

The Python validation script (resources/scripts/validate_env.py) runs at the very start of every pipeline execution. It checks that all required environment variables and secrets are present before any compute-heavy stages run.

Variables Checked

Variable	Stage	Description
APP_NAME	all	Application name
DEPLOY_ENV	deploy	Target deployment environment
DOCKER_REGISTRY	build-container	Container registry URL
DOCKER_USER	build-container	Docker registry username
DOCKER_PASS	build-container	Docker registry password / token
DEPLOY_HOST	deploy	Target host IP or hostname

If any variable is missing, the script exits with code 1 and the pipeline aborts immediately, saving time and compute resources.

Local Testing

# All vars set → should pass
APP_NAME=my-svc DEPLOY_ENV=staging DOCKER_REGISTRY=r.io \
DOCKER_USER=admin DOCKER_PASS=secret DEPLOY_HOST=10.0.0.1 \
python3 resources/scripts/validate_env.py

# No vars set → should fail with exit code 1
python3 resources/scripts/validate_env.py

---

Post-deploy Verification

The Python verification script (resources/scripts/verify_deploy.py) runs as the final pipeline stage after deployment. It confirms the newly deployed container is healthy before the pipeline reports success.

Checks Performed

Check	Method	Pass Condition
Environment vars	os.environ lookup	All 4 required vars set
Container status	SSH + docker inspect	Container state is "running"
HTTP health probe	GET /health via urllib	HTTP 200 response

Variables Required

Variable	Description
APP_NAME	Application / service name
APP_PORT	Port the application listens on
DEPLOY_ENV	Target deployment environment
DEPLOY_HOST	Target host IP or hostname

If any check fails, the script exits with code 1 and the pipeline reports a failed deployment.

Local Testing

# All vars set (requires SSH access and a running container)
APP_NAME=order-service APP_PORT=8080 DEPLOY_ENV=staging DEPLOY_HOST=10.0.0.1 \
python3 resources/scripts/verify_deploy.py

# No vars set -> should fail with exit code 1
python3 resources/scripts/verify_deploy.py

---

Pipeline Stages

┌──────────────────────────┐
│  Pre-flight Validation   │  <- validate_env.py
└────────────┬─────────────┘
             v
┌──────────────────────────┐
│          Build           │  <- buildApp.groovy
└────────────┬─────────────┘
             v
┌──────────────────────────┐
│          Test            │  <- testApp.groovy
└────────────┬─────────────┘
             v
┌──────────────────────────┐
│   Build & Push Image     │  <- buildAndPushContainer.groovy
└────────────┬─────────────┘
             v
┌──────────────────────────┐
│         Deploy           │  <- deployApp.groovy
└────────────┬─────────────┘
             v
┌──────────────────────────┐
│ Post-deploy Verification │  <- verify_deploy.py
└──────────────────────────┘

---

Jenkins Credentials Required

Configure these in Manage Jenkins → Credentials:

Credential ID	Type	Description
docker-registry-credentials	Username/Password	Docker registry login
deploy-host-ip	Secret text	Target server IP / hostname

---

Metrics (Measured)

Metric	Traditional	Shared Library	Improvement
Total lines per Jenkinsfile	304	19	93.8%
Effective code lines	218	7	96.8%
Pipeline logic locations	N repos (copy-paste)	1 centralized repo	Centralized
Time to onboard new app	Hours	Minutes	~90%

Both Jenkinsfiles are in examples/ for side-by-side comparison.

---

Testing

Run all unit tests locally (no Jenkins required):

# Run pre-flight validation tests (11 tests)
python3 -m unittest tests.test_validate_env -v

# Run post-deploy verification tests (18 tests)
python3 -m unittest tests.test_verify_deploy -v

Pre-flight Validation Tests (test_validate_env.py)

Test Category	Count	Coverage
Happy path	1	All vars present -> pass
Failure paths	4	Missing, empty, whitespace, single missing
Result structure	3	Keys, totals, arithmetic
Custom input	1	Arbitrary var lists
Exit codes	2	sys.exit(0) / sys.exit(1)

Post-deploy Verification Tests (test_verify_deploy.py)

Test Category	Count	Coverage
Env var checking	4	All present, all missing, single missing, whitespace
Container checks	4	Running, exited, SSH failure, timeout
Health probes	3	HTTP 200, HTTP 503, unreachable
Verify orchestrator	5	All pass, env skip, container down, keys, arithmetic
Exit codes	2	sys.exit(0) / sys.exit(1)

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License

See LICENSE for details.