universe/k8s/lux-mainnet/chain-tip.yaml

# How old each Lux chain's newest block is, for the status pages.
#
# An RPC that answers eth_chainId says nothing about whether the chain still
# makes blocks: an archive with no peers answers every read. The status checks
# (hanzoai/universe charts/app/values/hanzo/status-lux.yaml, status-lux-config)
# read /v1/tip/<chain> here and hold age_seconds to a limit, so a chain that has
# stopped shows as down.
#
# The chain list is fixed in CHAINS; a request names a chain, never a URL. The
# only call made is eth_getBlockByNumber("latest"). ClusterIP only: nothing
# outside the cluster reaches this Service.
apiVersion: v1
kind: ConfigMap
metadata: {name: chain-tip-code, namespace: lux-mainnet}
data:
  tip.py: |
    import json, os, time, urllib.request
    from http.server import BaseHTTPRequestHandler, ThreadingHTTPServer

    CHAINS = json.loads(os.environ["CHAINS"])
    TIMEOUT = float(os.environ.get("TIMEOUT_SECONDS", "5"))
    CALL = json.dumps({"jsonrpc": "2.0", "id": 1, "method": "eth_getBlockByNumber",
                       "params": ["latest", False]}).encode()

    def tip(url):
        req = urllib.request.Request(url, CALL, {"content-type": "application/json", "user-agent": "lux-chain-tip"})
        with urllib.request.urlopen(req, timeout=TIMEOUT) as r:
            block = json.load(r)["result"]
        return int(block["number"], 16), int(block["timestamp"], 16)

    class Handler(BaseHTTPRequestHandler):
        def do_GET(self):
            if self.path == "/healthz":
                return self.reply(200, {"status": "ok"})
            prefix = "/v1/tip/"
            name = self.path[len(prefix):] if self.path.startswith(prefix) else ""
            if name not in CHAINS:
                return self.reply(404, {"error": "unknown chain", "chains": sorted(CHAINS)})
            try:
                height, stamp = tip(CHAINS[name])
            except Exception as e:
                return self.reply(502, {"chain": name, "error": type(e).__name__})
            self.reply(200, {"chain": name, "height": height, "timestamp": stamp,
                             "age_seconds": int(time.time()) - stamp})

        def reply(self, code, body):
            data = json.dumps(body).encode()
            self.send_response(code)
            self.send_header("content-type", "application/json")
            self.send_header("content-length", str(len(data)))
            self.end_headers()
            self.wfile.write(data)

        def log_message(self, *args):
            pass

    ThreadingHTTPServer(("", 8080), Handler).serve_forever()
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: chain-tip
  namespace: lux-mainnet
  labels: {app.kubernetes.io/name: chain-tip, app.kubernetes.io/part-of: lux}
spec:
  replicas: 1
  selector:
    matchLabels: {app.kubernetes.io/name: chain-tip}
  template:
    metadata:
      labels: {app.kubernetes.io/name: chain-tip, app.kubernetes.io/part-of: lux}
    spec:
      automountServiceAccountToken: false
      enableServiceLinks: false
      nodeSelector:
        kubernetes.io/arch: amd64
        hanzo.ai/role: apps
      securityContext:
        runAsUser: 65532
        runAsGroup: 65532
        runAsNonRoot: true
        seccompProfile: {type: RuntimeDefault}
      containers:
      - name: tip
        image: python:3.12-alpine@sha256:6d43704baacd1bfbe7c295d7f13079d5d8104ed33568873133f8fc69980419df
        command: [python, -u, /app/tip.py]
        env:
        - name: CHAINS
          value: '{"lux-mainnet":"http://luxd-archive.lux-mainnet.svc.cluster.local:9630/v1/chain/C/rpc","lux-testnet":"http://luxd-archive.lux-testnet.svc.cluster.local:9630/v1/chain/C/rpc"}'
        ports:
        - {name: http, containerPort: 8080}
        readinessProbe:
          httpGet: {path: /healthz, port: http}
          periodSeconds: 10
        livenessProbe:
          httpGet: {path: /healthz, port: http}
          periodSeconds: 30
        resources:
          requests: {cpu: 5m, memory: 24Mi}
          limits: {cpu: 100m, memory: 64Mi}
        securityContext:
          allowPrivilegeEscalation: false
          readOnlyRootFilesystem: true
          capabilities: {drop: [ALL]}
        volumeMounts:
        - {name: code, mountPath: /app, readOnly: true}
      volumes:
      - name: code
        configMap: {name: chain-tip-code}
---
apiVersion: v1
kind: Service
metadata:
  name: chain-tip
  namespace: lux-mainnet
  labels: {app.kubernetes.io/name: chain-tip, app.kubernetes.io/part-of: lux}
spec:
  selector: {app.kubernetes.io/name: chain-tip}
  ports:
  - {name: http, port: 80, targetPort: http}