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)
+	}
+}