feat: add xrpl health/readiness checks

images/go_chains_hc/README.md

@@ -1,27 +1,37 @@
 ## Connected Chains Healthcheck
 
-A minimal Go binary/container that exposes a `/readyz` HTTP endpoint for blockchain node readiness probes. Designed to be used alongside any compatible node (Bitcoin, Dogecoin, Litecoin, etc.) in a Kubernetes pod.
+A minimal Go binary/container that exposes a `/readyz` HTTP endpoint for blockchain node readiness probes. Designed to be used alongside any compatible node in a Kubernetes pod or as standalone Docker service.
 
 ### How it works
 
 On each `/readyz` request, the sidecar runs a configurable set of checks against the node's JSON-RPC API. It returns 200 OK when all checks pass, or an error with a message on the first failing check.
 
 ### Checks
 
+#### Bitcoin / Dogecoin
+
 | Check | RPC Method | Description |
 |---|---|---|
-| `blockdownload` | `getblockchaininfo` | Passes when `initialblockdownload` is `false`. Default for all chains. |
+| `blockdownload` | `getblockchaininfo` | Passes when `initialblockdownload` is `false` |
 | `txindex` | `getindexinfo` | Passes when `txindex.synced` is `true`. |
 | `connectioncount` | `getconnectioncount` | Passes when the node has at least `MIN_CONNECTIONS` peers. |
 
+#### XRPL
+
+| Check | RPC Method | Description |
+|---|---|---|
+| `serverstatus` | `ping` | Passes when `status` is `success` |
+| `nodesynced` | `server_info` | Passes when `server_state` is `full`\|`proposing`\|`validating`. |
+| `peercount` | `server_info` | Passes when the node has at least `MIN_CONNECTIONS` peers. |
+
 ### Environment Variables
 
 | Variable | Required | Default | Description |
 |---|---|---|---|
 | `NODE_URL` | yes | — | RPC endpoint, e.g. `http://localhost:8332` |
 | `NODE_USER` | no | — | RPC auth username |
 | `NODE_PASS` | no | — | RPC auth password |
-| `CHECKS` | no | `blockdownload` | Comma-separated list of checks to run (`blockdownload, txindex, connectioncount`) |
+| `CHECKS` | yes | - | Comma-separated list of checks to run (Check above section) |
 | `MIN_CONNECTIONS` | no | `8` | Minimum peer connections required for the `connectioncount` check |
 | `DEBUG` | no | `false` | Enable debug logs |
 

images/go_chains_hc/checks.go

@@ -15,9 +15,15 @@ type Check func(ctx context.Context, client *http.Client, cfg Config) error
 const jsonRPCVersion = "2.0"
 
 var registry = map[string]Check{
+	// BTC/Dogecoin
 	"blockdownload":   checkBlockDownload,
 	"txindex":         checkTxIndex,
 	"connectioncount": checkConnectionCount,
+
+	// Ripple
+	"nodesynced":   checkNodeServerState,
+	"peercount":    checkPeerCount,
+	"serverstatus": checkServerStatus,
 }
 
 type rpcRequest struct {
@@ -139,3 +145,74 @@ func checkConnectionCount(ctx context.Context, client *http.Client, cfg Config)
 
 	return nil
 }
+
+func checkServerStatus(ctx context.Context, client *http.Client, cfg Config) error {
+	result, err := doRPC(ctx, client, cfg, "ping")
+	if err != nil {
+		return err
+	}
+
+	var info struct {
+		Status string `json:"status"`
+	}
+	if err := json.Unmarshal(result, &info); err != nil {
+		return fmt.Errorf("parse ping response: %w", err)
+	}
+	if info.Status != "success" {
+		return fmt.Errorf("unexpected status: %q", info.Status)
+	}
+
+	return nil
+}
+
+func checkNodeServerState(ctx context.Context, client *http.Client, cfg Config) error {
+	result, err := doRPC(ctx, client, cfg, "server_info")
+	if err != nil {
+		return err
+	}
+
+	var info struct {
+		State struct {
+			ServerState string `json:"server_state"`
+		} `json:"info"`
+	}
+
+	if err := json.Unmarshal(result, &info); err != nil {
+		return fmt.Errorf("parse server_state response: %w", err)
+	}
+
+	validServerStates := map[string]bool{
+		"full":       true,
+		"validating": true,
+		"proposing":  true,
+	}
+
+	if !validServerStates[info.State.ServerState] {
+		return fmt.Errorf("unexpected server_state: %q", info.State.ServerState)
+	}
+
+	return nil
+}
+
+func checkPeerCount(ctx context.Context, client *http.Client, cfg Config) error {
+	result, err := doRPC(ctx, client, cfg, "server_info")
+	if err != nil {
+		return err
+	}
+
+	var info struct {
+		State struct {
+			Peers int `json:"peers"`
+		} `json:"info"`
+	}
+
+	if err := json.Unmarshal(result, &info); err != nil {
+		return fmt.Errorf("parse server_state response: %w", err)
+	}
+
+	if info.State.Peers < cfg.MinConnections {
+		return fmt.Errorf("not enough peers: %d < %d", info.State.Peers, cfg.MinConnections)
+	}
+
+	return nil
+}

images/go_chains_hc/main.go

@@ -29,9 +29,9 @@ func configFromEnv() (Config, error) {
 		return Config{}, fmt.Errorf("NODE_URL is required")
 	}
 
-	checks := []string{"blockdownload"}
-	if raw := os.Getenv("CHECKS"); raw != "" {
-		checks = strings.Split(raw, ",")
+	checks := strings.Split(os.Getenv("CHECKS"), ",")
+	if len(checks) == 0 || checks[0] == "" {
+		return Config{}, fmt.Errorf("CHECKS is required")
 	}
 
 	for _, name := range checks {