k8s provider for stackql

This repository is used to generate and document the k8s provider for StackQL, allowing you to query and manipulate Kubernetes resources using SQL-like syntax. The provider is built using the @stackql/provider-utils package, which provides tools for converting OpenAPI specifications into StackQL-compatible provider schemas.

Prerequisites

To use the Kubernetes provider with StackQL, you'll need:

1. Access to a Kubernetes cluster with appropriate permissions
2. A properly configured kubectl with a valid kubeconfig file
3. StackQL CLI installed on your system (see StackQL)

1. Download the Open API Specification

First, download the Kubernetes OpenAPI specification from your target cluster:

mkdir -p provider-dev/downloaded

# Option 1: Download directly from a running cluster
kubectl get --raw /openapi/v2 > provider-dev/downloaded/k8s-openapi.json

# Option 2: Or fetch from a specific Kubernetes version
curl -L https://raw.githubusercontent.com/kubernetes/kubernetes/release-1.28/api/openapi-spec/swagger.json \
  -o provider-dev/downloaded/k8s-openapi.json

2. Split into Service Specs

Next, split the monolithic OpenAPI specification into service-specific files:

rm -rf provider-dev/source/*
npm run split -- \
  --provider-name k8s \
  --api-doc provider-dev/downloaded/k8s-openapi.json \
  --svc-discriminator group \
  --output-dir provider-dev/source \
  --overwrite \
  --svc-name-overrides "$(cat <<EOF
{
  "apps": "apps",
  "core": "core",
  "networking.k8s.io": "networking",
  "batch": "batch",
  "storage.k8s.io": "storage",
  "rbac.authorization.k8s.io": "rbac",
  "apiextensions.k8s.io": "apiextensions",
  "policy": "policy",
  "autoscaling": "autoscaling",
  "admissionregistration.k8s.io": "admissionregistration",
  "certificates.k8s.io": "certificates"
}
EOF
)"

3. Generate Mappings

Generate the mapping configuration that connects OpenAPI operations to StackQL resources:

npm run generate-mappings -- \
  --provider-name k8s \
  --input-dir provider-dev/source \
  --output-dir provider-dev/config

Update the resultant provider-dev/config/all_services.csv to add the stackql_resource_name, stackql_method_name, stackql_verb values for each operation.

4. Generate Provider

This step transforms the split OpenAPI service specs into a fully-functional StackQL provider by applying the resource and method mappings defined in your CSV file.

rm -rf provider-dev/openapi/*
npm run generate-provider -- \
  --provider-name k8s \
  --input-dir provider-dev/source \
  --output-dir provider-dev/openapi/src/k8s \
  --config-path provider-dev/config/all_services.csv \
  --servers '[{"url": "https://kubernetes.default.svc"}]' \
  --provider-config '{"auth": {"type": "k8s", "credentialsenvvar": "KUBECONFIG"}}' \
  --overwrite

5. Test Provider

Starting the StackQL Server

Before running tests, start a StackQL server with your provider:

PROVIDER_REGISTRY_ROOT_DIR="$(pwd)/provider-dev/openapi"
npm run start-server -- --provider k8s --registry $PROVIDER_REGISTRY_ROOT_DIR

Test Meta Routes

Test all metadata routes (services, resources, methods) in the provider:

npm run test-meta-routes -- k8s --verbose

When you're done testing, stop the StackQL server:

npm run stop-server

Use this command to view the server status:

npm run server-status

Run test queries

Run some test queries against the provider using the stackql shell:

PROVIDER_REGISTRY_ROOT_DIR="$(pwd)/provider-dev/openapi"
REG_STR='{"url": "file://'${PROVIDER_REGISTRY_ROOT_DIR}'", "localDocRoot": "'${PROVIDER_REGISTRY_ROOT_DIR}'", "verifyConfig": {"nopVerify": true}}'
./stackql shell --registry="${REG_STR}"

Example queries to try:

-- List all namespaces
SELECT 
metadata.name,
metadata.creation_timestamp,
status.phase
FROM k8s.core.namespaces;

-- List all pods in all namespaces
SELECT 
metadata.name,
metadata.namespace,
status.phase,
status.pod_ip,
status.host_ip,
spec.node_name
FROM k8s.core.pods_all_namespaces;

-- List all deployments
SELECT 
metadata.name,
metadata.namespace,
spec.replicas,
status.ready_replicas,
status.available_replicas,
status.unavailable_replicas
FROM k8s.apps.deployments_all_namespaces;

-- List all nodes and their conditions
SELECT 
n.metadata.name,
n.status.capacity,
n.status.allocatable,
c.type,
c.status,
c.last_transition_time
FROM k8s.core.nodes n,
UNNEST(n.status.conditions) AS c;

-- Get information about persistent volumes
SELECT 
metadata.name,
spec.capacity,
spec.access_modes,
spec.persistent_volume_reclaim_policy,
spec.storage_class_name,
status.phase
FROM k8s.core.persistent_volumes;

-- Check RBAC roles and bindings
SELECT 
metadata.name,
metadata.namespace,
rules
FROM k8s.rbac.roles_all_namespaces;

6. Publish the provider

To publish the provider push the k8s dir to providers/src in a feature branch of the stackql-provider-registry. Follow the registry release flow.

Launch the StackQL shell:

export DEV_REG="{ \"url\": \"https://registry-dev.stackql.app/providers\" }"
./stackql --registry="${DEV_REG}" shell

Pull the latest dev k8s provider:

registry pull k8s;

Run some test queries to verify the provider works as expected.

7. Generate web docs

Provider doc microsites are built using Docusaurus and published using GitHub Pages.

a. Update headerContent1.txt and headerContent2.txt accordingly in provider-dev/docgen/provider-data/

b. Update the following in website/docusaurus.config.js:

// Provider configuration - change these for different providers
const providerName = "k8s";
const providerTitle = "Kubernetes Provider";

c. Then generate docs using...

npm run generate-docs -- \
  --provider-name k8s \
  --provider-dir ./provider-dev/openapi/src/k8s/v00.00.00000 \
  --output-dir ./website \
  --provider-data-dir ./provider-dev/docgen/provider-data

8. Test web docs locally

cd website
# test build
yarn build

# run local dev server
yarn start

9. Publish web docs to GitHub Pages

Under Pages in the repository, in the Build and deployment section select GitHub Actions as the Source. In Netlify DNS create the following records:

Source Domain	Record Type	Target
k8s-provider.stackql.io	CNAME	stackql.github.io.

License

MIT

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.