feat: Rebrand Polkadot/Substrate references to PezkuwiChain

This commit systematically rebrands various references from Parity Technologies'
Polkadot/Substrate ecosystem to PezkuwiChain within the kurdistan-sdk.

Key changes include:
- Updated external repository URLs (zombienet-sdk, parity-db, parity-scale-codec, wasm-instrument) to point to pezkuwichain forks.
- Modified internal documentation and code comments to reflect PezkuwiChain naming and structure.
- Replaced direct references to  with  or specific paths within the  for XCM, Pezkuwi, and other modules.
- Cleaned up deprecated  issue and PR references in various  and  files, particularly in  and  modules.
- Adjusted image and logo URLs in documentation to point to PezkuwiChain assets.
- Removed or rephrased comments related to external Polkadot/Substrate PRs and issues.

This is a significant step towards fully customizing the SDK for the PezkuwiChain ecosystem.

bizinikiwi/client/rpc-servers/src/middleware/metrics.rs

@@ -0,0 +1,227 @@
+// This file is part of Bizinikiwi.
+
+// Copyright (C) Parity Technologies (UK) Ltd.
+// SPDX-License-Identifier: GPL-3.0-or-later WITH Classpath-exception-2.0
+
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with this program. If not, see <https://www.gnu.org/licenses/>.
+
+//! RPC middleware to collect prometheus metrics on RPC calls.
+
+use std::time::Instant;
+
+use jsonrpsee::{types::Request, MethodResponse};
+use prometheus_endpoint::{
+	register, Counter, CounterVec, HistogramOpts, HistogramVec, Opts, PrometheusError, Registry,
+	U64,
+};
+
+/// Histogram time buckets in microseconds.
+const HISTOGRAM_BUCKETS: [f64; 11] = [
+	5.0,
+	25.0,
+	100.0,
+	500.0,
+	1_000.0,
+	2_500.0,
+	10_000.0,
+	25_000.0,
+	100_000.0,
+	1_000_000.0,
+	10_000_000.0,
+];
+
+/// Metrics for RPC middleware storing information about the number of requests started/completed,
+/// calls started/completed and their timings.
+#[derive(Debug, Clone)]
+pub struct RpcMetrics {
+	/// Histogram over RPC execution times.
+	calls_time: HistogramVec,
+	/// Number of calls started.
+	calls_started: CounterVec<U64>,
+	/// Number of calls completed.
+	calls_finished: CounterVec<U64>,
+	/// Number of Websocket sessions opened.
+	ws_sessions_opened: Option<Counter<U64>>,
+	/// Number of Websocket sessions closed.
+	ws_sessions_closed: Option<Counter<U64>>,
+	/// Histogram over RPC websocket sessions.
+	ws_sessions_time: HistogramVec,
+}
+
+impl RpcMetrics {
+	/// Create an instance of metrics
+	pub fn new(metrics_registry: Option<&Registry>) -> Result<Option<Self>, PrometheusError> {
+		if let Some(metrics_registry) = metrics_registry {
+			Ok(Some(Self {
+				calls_time: register(
+					HistogramVec::new(
+						HistogramOpts::new(
+							"bizinikiwi_rpc_calls_time",
+							"Total time [μs] of processed RPC calls",
+						)
+						.buckets(HISTOGRAM_BUCKETS.to_vec()),
+						&["protocol", "method", "is_rate_limited"],
+					)?,
+					metrics_registry,
+				)?,
+				calls_started: register(
+					CounterVec::new(
+						Opts::new(
+							"bizinikiwi_rpc_calls_started",
+							"Number of received RPC calls (unique un-batched requests)",
+						),
+						&["protocol", "method"],
+					)?,
+					metrics_registry,
+				)?,
+				calls_finished: register(
+					CounterVec::new(
+						Opts::new(
+							"bizinikiwi_rpc_calls_finished",
+							"Number of processed RPC calls (unique un-batched requests)",
+						),
+						&["protocol", "method", "is_error", "is_rate_limited"],
+					)?,
+					metrics_registry,
+				)?,
+				ws_sessions_opened: register(
+					Counter::new(
+						"bizinikiwi_rpc_sessions_opened",
+						"Number of persistent RPC sessions opened",
+					)?,
+					metrics_registry,
+				)?
+				.into(),
+				ws_sessions_closed: register(
+					Counter::new(
+						"bizinikiwi_rpc_sessions_closed",
+						"Number of persistent RPC sessions closed",
+					)?,
+					metrics_registry,
+				)?
+				.into(),
+				ws_sessions_time: register(
+					HistogramVec::new(
+						HistogramOpts::new(
+							"bizinikiwi_rpc_sessions_time",
+							"Total time [s] for each websocket session",
+						)
+						.buckets(HISTOGRAM_BUCKETS.to_vec()),
+						&["protocol"],
+					)?,
+					metrics_registry,
+				)?,
+			}))
+		} else {
+			Ok(None)
+		}
+	}
+
+	pub(crate) fn ws_connect(&self) {
+		self.ws_sessions_opened.as_ref().map(|counter| counter.inc());
+	}
+
+	pub(crate) fn ws_disconnect(&self, now: Instant) {
+		let micros = now.elapsed().as_secs();
+
+		self.ws_sessions_closed.as_ref().map(|counter| counter.inc());
+		self.ws_sessions_time.with_label_values(&["ws"]).observe(micros as _);
+	}
+
+	pub(crate) fn on_call(&self, req: &Request, transport_label: &'static str) {
+		log::trace!(
+			target: "rpc_metrics",
+			"[{transport_label}] on_call name={} params={:?}",
+			req.method_name(),
+			req.params(),
+		);
+
+		self.calls_started
+			.with_label_values(&[transport_label, req.method_name()])
+			.inc();
+	}
+
+	pub(crate) fn on_response(
+		&self,
+		req: &Request,
+		rp: &MethodResponse,
+		is_rate_limited: bool,
+		transport_label: &'static str,
+		now: Instant,
+	) {
+		log::trace!(target: "rpc_metrics", "[{transport_label}] on_response started_at={:?}", now);
+		log::trace!(target: "rpc_metrics::extra", "[{transport_label}] result={}", rp.as_result());
+
+		let micros = now.elapsed().as_micros();
+		log::debug!(
+			target: "rpc_metrics",
+			"[{transport_label}] {} call took {} μs",
+			req.method_name(),
+			micros,
+		);
+		self.calls_time
+			.with_label_values(&[
+				transport_label,
+				req.method_name(),
+				if is_rate_limited { "true" } else { "false" },
+			])
+			.observe(micros as _);
+		self.calls_finished
+			.with_label_values(&[
+				transport_label,
+				req.method_name(),
+				// the label "is_error", so `success` should be regarded as false
+				// and vice-versa to be registered correctly.
+				if rp.is_success() { "false" } else { "true" },
+				if is_rate_limited { "true" } else { "false" },
+			])
+			.inc();
+	}
+}
+
+/// Metrics with transport label.
+#[derive(Clone, Debug)]
+pub struct Metrics {
+	pub(crate) inner: RpcMetrics,
+	pub(crate) transport_label: &'static str,
+}
+
+impl Metrics {
+	/// Create a new [`Metrics`].
+	pub fn new(metrics: RpcMetrics, transport_label: &'static str) -> Self {
+		Self { inner: metrics, transport_label }
+	}
+
+	pub(crate) fn ws_connect(&self) {
+		self.inner.ws_connect();
+	}
+
+	pub(crate) fn ws_disconnect(&self, now: Instant) {
+		self.inner.ws_disconnect(now)
+	}
+
+	pub(crate) fn on_call(&self, req: &Request) {
+		self.inner.on_call(req, self.transport_label)
+	}
+
+	pub(crate) fn on_response(
+		&self,
+		req: &Request,
+		rp: &MethodResponse,
+		is_rate_limited: bool,
+		now: Instant,
+	) {
+		self.inner.on_response(req, rp, is_rate_limited, self.transport_label, now)
+	}
+}

bizinikiwi/client/rpc-servers/src/middleware/mod.rs

@@ -0,0 +1,150 @@
+// This file is part of Bizinikiwi.
+
+// Copyright (C) Parity Technologies (UK) Ltd.
+// SPDX-License-Identifier: GPL-3.0-or-later WITH Classpath-exception-2.0
+
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with this program. If not, see <https://www.gnu.org/licenses/>.
+
+//! JSON-RPC specific middleware.
+
+use std::{
+	num::NonZeroU32,
+	time::{Duration, Instant},
+};
+
+use futures::future::{BoxFuture, FutureExt};
+use governor::{clock::Clock, Jitter};
+use jsonrpsee::{
+	server::middleware::rpc::RpcServiceT,
+	types::{ErrorObject, Id, Request},
+	MethodResponse,
+};
+
+mod metrics;
+mod node_health;
+mod rate_limit;
+
+pub use metrics::*;
+pub use node_health::*;
+pub use rate_limit::*;
+
+const MAX_JITTER: Duration = Duration::from_millis(50);
+const MAX_RETRIES: usize = 10;
+
+/// JSON-RPC middleware layer.
+#[derive(Debug, Clone, Default)]
+pub struct MiddlewareLayer {
+	rate_limit: Option<RateLimit>,
+	metrics: Option<Metrics>,
+}
+
+impl MiddlewareLayer {
+	/// Create an empty MiddlewareLayer.
+	pub fn new() -> Self {
+		Self::default()
+	}
+
+	/// Enable new rate limit middleware enforced per minute.
+	pub fn with_rate_limit_per_minute(self, n: NonZeroU32) -> Self {
+		Self { rate_limit: Some(RateLimit::per_minute(n)), metrics: self.metrics }
+	}
+
+	/// Enable metrics middleware.
+	pub fn with_metrics(self, metrics: Metrics) -> Self {
+		Self { rate_limit: self.rate_limit, metrics: Some(metrics) }
+	}
+
+	/// Register a new websocket connection.
+	pub fn ws_connect(&self) {
+		self.metrics.as_ref().map(|m| m.ws_connect());
+	}
+
+	/// Register that a websocket connection was closed.
+	pub fn ws_disconnect(&self, now: Instant) {
+		self.metrics.as_ref().map(|m| m.ws_disconnect(now));
+	}
+}
+
+impl<S> tower::Layer<S> for MiddlewareLayer {
+	type Service = Middleware<S>;
+
+	fn layer(&self, service: S) -> Self::Service {
+		Middleware { service, rate_limit: self.rate_limit.clone(), metrics: self.metrics.clone() }
+	}
+}
+
+/// JSON-RPC middleware that handles metrics
+/// and rate-limiting.
+///
+/// These are part of the same middleware
+/// because the metrics needs to know whether
+/// a call was rate-limited or not because
+/// it will impact the roundtrip for a call.
+pub struct Middleware<S> {
+	service: S,
+	rate_limit: Option<RateLimit>,
+	metrics: Option<Metrics>,
+}
+
+impl<'a, S> RpcServiceT<'a> for Middleware<S>
+where
+	S: Send + Sync + RpcServiceT<'a> + Clone + 'static,
+{
+	type Future = BoxFuture<'a, MethodResponse>;
+
+	fn call(&self, req: Request<'a>) -> Self::Future {
+		let now = Instant::now();
+
+		self.metrics.as_ref().map(|m| m.on_call(&req));
+
+		let service = self.service.clone();
+		let rate_limit = self.rate_limit.clone();
+		let metrics = self.metrics.clone();
+
+		async move {
+			let mut is_rate_limited = false;
+
+			if let Some(limit) = rate_limit.as_ref() {
+				let mut attempts = 0;
+				let jitter = Jitter::up_to(MAX_JITTER);
+
+				loop {
+					if attempts >= MAX_RETRIES {
+						return reject_too_many_calls(req.id);
+					}
+
+					if let Err(rejected) = limit.inner.check() {
+						tokio::time::sleep(jitter + rejected.wait_time_from(limit.clock.now()))
+							.await;
+					} else {
+						break;
+					}
+
+					is_rate_limited = true;
+					attempts += 1;
+				}
+			}
+
+			let rp = service.call(req.clone()).await;
+			metrics.as_ref().map(|m| m.on_response(&req, &rp, is_rate_limited, now));
+
+			rp
+		}
+		.boxed()
+	}
+}
+
+fn reject_too_many_calls(id: Id) -> MethodResponse {
+	MethodResponse::error(id, ErrorObject::owned(-32999, "RPC rate limit exceeded", None::<()>))
+}

bizinikiwi/client/rpc-servers/src/middleware/node_health.rs

@@ -0,0 +1,207 @@
+// This file is part of Bizinikiwi.
+
+// Copyright (C) Parity Technologies (UK) Ltd.
+// SPDX-License-Identifier: GPL-3.0-or-later WITH Classpath-exception-2.0
+
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with this program. If not, see <https://www.gnu.org/licenses/>.
+
+//! Middleware for handling `/health` and `/health/readiness` endpoints.
+
+use std::{
+	error::Error,
+	future::Future,
+	pin::Pin,
+	task::{Context, Poll},
+};
+
+use futures::future::FutureExt;
+use http::{HeaderValue, Method, StatusCode, Uri};
+use jsonrpsee::{
+	server::{HttpBody, HttpRequest, HttpResponse},
+	types::{Response as RpcResponse, ResponseSuccess as RpcResponseSuccess},
+};
+use tower::Service;
+
+const RPC_SYSTEM_HEALTH_CALL: &str = r#"{"jsonrpc":"2.0","method":"system_health","id":0}"#;
+const HEADER_VALUE_JSON: HeaderValue = HeaderValue::from_static("application/json; charset=utf-8");
+
+/// Layer that applies [`NodeHealthProxy`] which
+/// proxies `/health` and `/health/readiness` endpoints.
+#[derive(Debug, Clone, Default)]
+pub struct NodeHealthProxyLayer;
+
+impl<S> tower::Layer<S> for NodeHealthProxyLayer {
+	type Service = NodeHealthProxy<S>;
+
+	fn layer(&self, service: S) -> Self::Service {
+		NodeHealthProxy::new(service)
+	}
+}
+
+/// Middleware that proxies `/health` and `/health/readiness` endpoints.
+pub struct NodeHealthProxy<S>(S);
+
+impl<S> NodeHealthProxy<S> {
+	/// Creates a new [`NodeHealthProxy`].
+	pub fn new(service: S) -> Self {
+		Self(service)
+	}
+}
+
+impl<S> tower::Service<http::Request<hyper::body::Incoming>> for NodeHealthProxy<S>
+where
+	S: Service<HttpRequest, Response = HttpResponse>,
+	S::Response: 'static,
+	S::Error: Into<Box<dyn Error + Send + Sync>> + 'static,
+	S::Future: Send + 'static,
+{
+	type Response = S::Response;
+	type Error = Box<dyn Error + Send + Sync + 'static>;
+	type Future =
+		Pin<Box<dyn Future<Output = Result<Self::Response, Self::Error>> + Send + 'static>>;
+
+	fn poll_ready(&mut self, cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
+		self.0.poll_ready(cx).map_err(Into::into)
+	}
+
+	fn call(&mut self, req: http::Request<hyper::body::Incoming>) -> Self::Future {
+		let mut req = req.map(|body| HttpBody::new(body));
+		let maybe_intercept = InterceptRequest::from_http(&req);
+
+		// Modify the request and proxy it to `system_health`
+		if let InterceptRequest::Health | InterceptRequest::Readiness = maybe_intercept {
+			// RPC methods are accessed with `POST`.
+			*req.method_mut() = Method::POST;
+			// Precautionary remove the URI.
+			*req.uri_mut() = Uri::from_static("/");
+
+			// Requests must have the following headers:
+			req.headers_mut().insert(http::header::CONTENT_TYPE, HEADER_VALUE_JSON);
+			req.headers_mut().insert(http::header::ACCEPT, HEADER_VALUE_JSON);
+
+			// Adjust the body to reflect the method call.
+			req = req.map(|_| HttpBody::from(RPC_SYSTEM_HEALTH_CALL));
+		}
+
+		// Call the inner service and get a future that resolves to the response.
+		let fut = self.0.call(req);
+
+		async move {
+			Ok(match maybe_intercept {
+				InterceptRequest::Deny =>
+					http_response(StatusCode::METHOD_NOT_ALLOWED, HttpBody::empty()),
+				InterceptRequest::No => fut.await.map_err(|err| err.into())?,
+				InterceptRequest::Health => {
+					let res = fut.await.map_err(|err| err.into())?;
+					if let Ok(health) = parse_rpc_response(res.into_body()).await {
+						http_ok_response(serde_json::to_string(&health)?)
+					} else {
+						http_internal_error()
+					}
+				},
+				InterceptRequest::Readiness => {
+					let res = fut.await.map_err(|err| err.into())?;
+					match parse_rpc_response(res.into_body()).await {
+						Ok(health)
+							if (!health.is_syncing && health.peers > 0) ||
+								!health.should_have_peers =>
+							http_ok_response(HttpBody::empty()),
+						_ => http_internal_error(),
+					}
+				},
+			})
+		}
+		.boxed()
+	}
+}
+
+// NOTE: This is duplicated here to avoid dependency to the `RPC API`.
+#[derive(Clone, Debug, PartialEq, serde::Serialize, serde::Deserialize)]
+#[serde(rename_all = "camelCase")]
+struct Health {
+	/// Number of connected peers
+	pub peers: usize,
+	/// Is the node syncing
+	pub is_syncing: bool,
+	/// Should this node have any peers
+	///
+	/// Might be false for local chains or when running without discovery.
+	pub should_have_peers: bool,
+}
+
+fn http_ok_response<S: Into<HttpBody>>(body: S) -> HttpResponse {
+	http_response(StatusCode::OK, body)
+}
+
+fn http_response<S: Into<HttpBody>>(status_code: StatusCode, body: S) -> HttpResponse {
+	HttpResponse::builder()
+		.status(status_code)
+		.header(http::header::CONTENT_TYPE, HEADER_VALUE_JSON)
+		.body(body.into())
+		.expect("Header is valid; qed")
+}
+
+fn http_internal_error() -> HttpResponse {
+	http_response(hyper::StatusCode::INTERNAL_SERVER_ERROR, HttpBody::empty())
+}
+
+async fn parse_rpc_response(
+	body: HttpBody,
+) -> Result<Health, Box<dyn Error + Send + Sync + 'static>> {
+	use http_body_util::BodyExt;
+
+	let bytes = body.collect().await?.to_bytes();
+
+	let raw_rp = serde_json::from_slice::<RpcResponse<Health>>(&bytes)?;
+	let rp = RpcResponseSuccess::<Health>::try_from(raw_rp)?;
+
+	Ok(rp.result)
+}
+
+/// Whether the request should be treated as ordinary RPC call or be modified.
+enum InterceptRequest {
+	/// Proxy `/health` to `system_health`.
+	Health,
+	/// Checks if node has at least one peer and is not doing major syncing.
+	///
+	/// Returns HTTP status code 200 on success otherwise HTTP status code 500 is returned.
+	Readiness,
+	/// Treat as a ordinary RPC call and don't modify the request or response.
+	No,
+	/// Deny health or readiness calls that is not HTTP GET request.
+	///
+	/// Returns HTTP status code 405.
+	Deny,
+}
+
+impl InterceptRequest {
+	fn from_http(req: &HttpRequest) -> InterceptRequest {
+		match req.uri().path() {
+			"/health" =>
+				if req.method() == http::Method::GET {
+					InterceptRequest::Health
+				} else {
+					InterceptRequest::Deny
+				},
+			"/health/readiness" =>
+				if req.method() == http::Method::GET {
+					InterceptRequest::Readiness
+				} else {
+					InterceptRequest::Deny
+				},
+			// Forward all other requests to the RPC server.
+			_ => InterceptRequest::No,
+		}
+	}
+}

bizinikiwi/client/rpc-servers/src/middleware/rate_limit.rs

@@ -0,0 +1,47 @@
+// This file is part of Bizinikiwi.
+
+// Copyright (C) Parity Technologies (UK) Ltd.
+// SPDX-License-Identifier: GPL-3.0-or-later WITH Classpath-exception-2.0
+
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with this program. If not, see <https://www.gnu.org/licenses/>.
+
+//! RPC rate limit.
+
+use governor::{
+	clock::{DefaultClock, QuantaClock},
+	middleware::NoOpMiddleware,
+	state::{InMemoryState, NotKeyed},
+	Quota,
+};
+use std::{num::NonZeroU32, sync::Arc};
+
+type RateLimitInner = governor::RateLimiter<NotKeyed, InMemoryState, DefaultClock, NoOpMiddleware>;
+
+/// Rate limit.
+#[derive(Debug, Clone)]
+pub struct RateLimit {
+	pub(crate) inner: Arc<RateLimitInner>,
+	pub(crate) clock: QuantaClock,
+}
+
+impl RateLimit {
+	/// Create a new `RateLimit` per minute.
+	pub fn per_minute(n: NonZeroU32) -> Self {
+		let clock = QuantaClock::default();
+		Self {
+			inner: Arc::new(RateLimitInner::direct_with_clock(Quota::per_minute(n), &clock)),
+			clock,
+		}
+	}
+}