Move parachain inherent data into its own crate (#326)

This renames and moves the `SystemInherentData` into its own crate. The struct is now called `ParachainInherentData`. Besides moving the struct, this also moves the code for creating this struct into this crate.
2026-05-30 11:41:02 +00:00 · 2021-02-11 13:05:17 +01:00
parent 119e0859b9
commit ba0bdc84a5
13 changed files with 445 additions and 305 deletions
@@ -0,0 +1,225 @@
+// Copyright 2021 Parity Technologies (UK) Ltd.
+// This file is part of Cumulus.
+
+// Substrate 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.
+
+// Substrate 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 Cumulus.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Client side code for generating the parachain inherent.
+
+use crate::ParachainInherentData;
+use codec::Decode;
+use cumulus_primitives_core::{
+	relay_chain::{
+		self,
+		v1::{HrmpChannelId, ParachainHost},
+		Block as PBlock, Hash as PHash,
+	},
+	InboundDownwardMessage, InboundHrmpMessage, ParaId, PersistedValidationData,
+};
+use sc_client_api::Backend;
+use sp_api::ProvideRuntimeApi;
+use sp_runtime::generic::BlockId;
+use sp_state_machine::Backend as _;
+use std::collections::BTreeMap;
+
+const LOG_TARGET: &str = "parachain-inherent";
+
+/// Returns the whole contents of the downward message queue for the parachain we are collating
+/// for.
+///
+/// Returns `None` in case of an error.
+fn retrieve_dmq_contents<PClient>(
+	polkadot_client: &PClient,
+	para_id: ParaId,
+	relay_parent: PHash,
+) -> Option<Vec<InboundDownwardMessage>>
+where
+	PClient: ProvideRuntimeApi<PBlock>,
+	PClient::Api: ParachainHost<PBlock>,
+{
+	polkadot_client
+		.runtime_api()
+		.dmq_contents_with_context(
+			&BlockId::hash(relay_parent),
+			sp_core::ExecutionContext::Importing,
+			para_id,
+		)
+		.map_err(|e| {
+			tracing::error!(
+				target: LOG_TARGET,
+				relay_parent = ?relay_parent,
+				error = ?e,
+				"An error occured during requesting the downward messages.",
+			);
+		})
+		.ok()
+}
+
+/// Returns channels contents for each inbound HRMP channel addressed to the parachain we are
+/// collating for.
+///
+/// Empty channels are also included.
+fn retrieve_all_inbound_hrmp_channel_contents<PClient>(
+	polkadot_client: &PClient,
+	para_id: ParaId,
+	relay_parent: PHash,
+) -> Option<BTreeMap<ParaId, Vec<InboundHrmpMessage>>>
+where
+	PClient: ProvideRuntimeApi<PBlock>,
+	PClient::Api: ParachainHost<PBlock>,
+{
+	polkadot_client
+		.runtime_api()
+		.inbound_hrmp_channels_contents_with_context(
+			&BlockId::hash(relay_parent),
+			sp_core::ExecutionContext::Importing,
+			para_id,
+		)
+		.map_err(|e| {
+			tracing::error!(
+				target: LOG_TARGET,
+				relay_parent = ?relay_parent,
+				error = ?e,
+				"An error occured during requesting the inbound HRMP messages.",
+			);
+		})
+		.ok()
+}
+
+/// Collect the relevant relay chain state in form of a proof for putting it into the validation
+/// data inherent.
+fn collect_relay_storage_proof(
+	polkadot_backend: &impl Backend<PBlock>,
+	para_id: ParaId,
+	relay_parent: PHash,
+) -> Option<sp_state_machine::StorageProof> {
+	use relay_chain::well_known_keys as relay_well_known_keys;
+
+	let relay_parent_state_backend = polkadot_backend
+		.state_at(BlockId::Hash(relay_parent))
+		.map_err(|e| {
+			tracing::error!(
+				target: LOG_TARGET,
+				relay_parent = ?relay_parent,
+				error = ?e,
+				"Cannot obtain the state of the relay chain.",
+			)
+		})
+		.ok()?;
+
+	let ingress_channels = relay_parent_state_backend
+		.storage(&relay_well_known_keys::hrmp_ingress_channel_index(para_id))
+		.map_err(|e| {
+			tracing::error!(
+				target: LOG_TARGET,
+				error = ?e,
+				"Cannot obtain the hrmp ingress channel index."
+			)
+		})
+		.ok()?;
+
+	let ingress_channels = ingress_channels
+		.map(|raw| <Vec<ParaId>>::decode(&mut &raw[..]))
+		.transpose()
+		.map_err(|e| {
+			tracing::error!(
+				target: LOG_TARGET,
+				error = ?e,
+				"Cannot decode the hrmp ingress channel index.",
+			)
+		})
+		.ok()?
+		.unwrap_or_default();
+
+	let egress_channels = relay_parent_state_backend
+		.storage(&relay_well_known_keys::hrmp_egress_channel_index(para_id))
+		.map_err(|e| {
+			tracing::error!(
+				target: LOG_TARGET,
+				error = ?e,
+				"Cannot obtain the hrmp egress channel index.",
+			)
+		})
+		.ok()?;
+	let egress_channels = egress_channels
+		.map(|raw| <Vec<ParaId>>::decode(&mut &raw[..]))
+		.transpose()
+		.map_err(|e| {
+			tracing::error!(
+				target: LOG_TARGET,
+				error = ?e,
+				"Cannot decode the hrmp egress channel index.",
+			)
+		})
+		.ok()?
+		.unwrap_or_default();
+
+	let mut relevant_keys = vec![];
+	relevant_keys.push(relay_well_known_keys::ACTIVE_CONFIG.to_vec());
+	relevant_keys.push(relay_well_known_keys::dmq_mqc_head(para_id));
+	relevant_keys.push(relay_well_known_keys::relay_dispatch_queue_size(para_id));
+	relevant_keys.push(relay_well_known_keys::hrmp_ingress_channel_index(para_id));
+	relevant_keys.push(relay_well_known_keys::hrmp_egress_channel_index(para_id));
+	relevant_keys.extend(ingress_channels.into_iter().map(|sender| {
+		relay_well_known_keys::hrmp_channels(HrmpChannelId {
+			sender,
+			recipient: para_id,
+		})
+	}));
+	relevant_keys.extend(egress_channels.into_iter().map(|recipient| {
+		relay_well_known_keys::hrmp_channels(HrmpChannelId {
+			sender: para_id,
+			recipient,
+		})
+	}));
+
+	sp_state_machine::prove_read(relay_parent_state_backend, relevant_keys)
+		.map_err(|e| {
+			tracing::error!(
+				target: LOG_TARGET,
+				relay_parent = ?relay_parent,
+				error = ?e,
+				"Failed to collect required relay chain state storage proof.",
+			)
+		})
+		.ok()
+}
+
+impl ParachainInherentData {
+	/// Create the [`ParachainInherentData`] at the given `relay_parent`.
+	///
+	/// Returns `None` if the creation failed.
+	pub fn create_at<PClient>(
+		relay_parent: PHash,
+		polkadot_client: &PClient,
+		polkadot_backend: &impl Backend<PBlock>,
+		validation_data: &PersistedValidationData,
+		para_id: ParaId,
+	) -> Option<ParachainInherentData>
+	where
+		PClient: ProvideRuntimeApi<PBlock>,
+		PClient::Api: ParachainHost<PBlock>,
+	{
+		let relay_chain_state = collect_relay_storage_proof(polkadot_backend, para_id, relay_parent)?;
+		let downward_messages = retrieve_dmq_contents(polkadot_client, para_id, relay_parent)?;
+		let horizontal_messages =
+			retrieve_all_inbound_hrmp_channel_contents(polkadot_client, para_id, relay_parent)?;
+
+		Some(ParachainInherentData {
+			downward_messages,
+			horizontal_messages,
+			validation_data: validation_data.clone(),
+			relay_chain_state,
+		})
+	}
+}