greentic-demo 0.4.0

NATS-to-Greentic runner bridge that powers the greentic-demo messaging flow.
Documentation

greentic-demo

Thin bootstrap that wires environment variables into greentic-runner-host. All runtime logic (pack resolution, caching, hot reload, telemetry, secrets, routing) happens inside the runner; this crate simply loads .env, builds a stable RunnerConfig, and calls runner_shim::run(cfg) so future runner releases can drop in without churn.

Quickstart

  1. Copy the defaults and edit as needed: 
    cp .env.example .env
$EDITOR .env
    Make sure PACKS_DIR points to a directory where each tenant has a bindings.yaml file.
  2. Start the runner with your packs/index: 
    make run
    make run sources .env, then runs cargo +nightly run --locked --bin greentic-demo so you always test the same dependency graph as CI.
  3. Update .env whenever you switch pack backends, cache directories, refresh intervals, or tenant routing strategies. dotenvy loads the file automatically at startup.

Docker Image

The multi-stage Dockerfile builds a MUSL binary and copies it into gcr.io/distroless/static:nonroot, keeping the final image around 25–30 MB. Targets cover the common flow:

make docker-build DOCKER_IMAGE=ghcr.io/greentic-ai/greentic-demo:local
make docker-run   DOCKER_IMAGE=ghcr.io/greentic-ai/greentic-demo:local

docker-run reads the current .env file and publishes ${PORT:-8080} by default.

Cloudflared Tunnel

Expose a local instance through Cloudflare Tunnel without poking firewall holes:

make tunnel

This target checks for cloudflared, sources .env, and runs cloudflared tunnel --url http://127.0.0.1:$PORT. See Cloudflare's docs for installing the CLI and authenticating your account.

Configuration Surface

cmd/greentic-demo/main.rs converts env vars into a stable RunnerConfig. The key knobs are:

Variable Description Default
PACKS_DIR Directory containing per-tenant bindings.yaml files ./packs
PORT HTTP listener exposed by the runner host 8080
SECRETS_BACKEND Hint for which secrets backend to bootstrap (env, aws, gcp, azure) env
PACK_SOURCE Resolver scheme (fs, http, oci, s3, gcs, azblob) fs
PACK_INDEX_URL Local path or URL to index.json ./examples/index.json
PACK_CACHE_DIR Content-addressed cache root .packs
PACK_REFRESH_INTERVAL Human-friendly interval (e.g. 30s, 5m) for hot-reload polling 30s
TENANT_RESOLVER Routing strategy: host, header, jwt, or env host
PACK_PUBLIC_KEY Optional Ed25519 key to verify signed packs unset

Additional runner features (telemetry presets, secrets bootstrap, admin APIs) will be surfaced directly through this config once the corresponding runner PRs land; the shim already has placeholders so the eventual cut-over is a one-liner re-export.

Development Notes

  • make fmt / make test run against cargo +nightly because the crate targets Rust 2024 edition.
  • .env is ignored by Git; make run automatically creates it from .env.example the first time.
  • Historical NATS bridge utilities (config, nats_bridge, etc.) remain available under src/ for reference, but new demos should run entirely through the runner host via this bootstrap.
  • See docs/deploy.md for the Terraform + GitHub Actions deployment flow, required OIDC identities, and how to trigger the Deploy workflow.

Deployment Demo Pack

examples/deployment/generic-deploy.gtpack is a provider-agnostic deployment example:

  • kind: deployment pack with an events flow deploy_generic_iac that hands off to a dummy deployment component (deploy.renderer kind).
  • Component manifest greentic.deploy.generic.iac advertises host.iac for writing IaC templates and imports greentic:deploy-plan@1.0.0.
  • Includes a basic configurator flow for the component.
  • A compiled stub WASM for greentic.deploy.generic.iac is included in the pack, generated from examples/deployment/stub-deploy-component. Rebuild it if you tweak the stub:
    • cd examples/deployment/stub-deploy-component
    • cargo build --release --target wasm32-wasip1
    • copy target/wasm32-wasip1/release/stub-deploy-component.wasm over examples/deployment/generic-deploy.gtpack/components/greentic.deploy.generic.iac.wasm
  • Discovery/run: the default PACK_INDEX_URL in .env.example already points to ./examples/index.json, which now includes the deployment demo under tenant deployment-demo. To run it locally, set TENANT_RESOLVER=env and TENANT=deployment-demo (or use a host/header resolver that maps to that tenant) before starting the runner.