fixup! feat(truapi-server): add Rust host runtime

Author: pgherveou

rust/crates/truapi-server/src/host_logic/statement_store/rpc.rs

@@ -0,0 +1,115 @@
+//! Statement-store JSON-RPC shapes mirrored from `sp_statement_store`.
+//!
+//! See the upstream RPC methods plus `TopicFilter` / `StatementEvent` types:
+//! <https://github.com/paritytech/polkadot-sdk/blob/f2f3aa6a8fda8ea52282da9711b3c5da4ba82529/substrate/client/rpc-api/src/statement/mod.rs#L19-L117>
+//! <https://github.com/paritytech/polkadot-sdk/blob/f2f3aa6a8fda8ea52282da9711b3c5da4ba82529/substrate/primitives/statement-store/src/store_api.rs#L41-L54>
+//! <https://github.com/paritytech/polkadot-sdk/blob/f2f3aa6a8fda8ea52282da9711b3c5da4ba82529/substrate/primitives/statement-store/src/store_api.rs#L204-L221>
+
+use serde_json::Value;
+
+use super::StatementStoreParseError;
+
+/// Statement-store RPC method used to open a topic subscription.
+pub const SUBSCRIBE_STATEMENT_METHOD: &str = "statement_subscribeStatement";
+/// Statement-store RPC method used to close a topic subscription.
+pub const UNSUBSCRIBE_STATEMENT_METHOD: &str = "statement_unsubscribeStatement";
+/// Statement-store RPC method used to submit a signed statement.
+pub const SUBMIT_STATEMENT_METHOD: &str = "statement_submit";
+/// Maximum `matchAll` topic count accepted by the statement-store RPC.
+pub const MAX_MATCH_ALL_TOPICS: usize = 4;
+/// Maximum `matchAny` topic count accepted by the statement-store RPC.
+pub const MAX_MATCH_ANY_TOPICS: usize = 128;
+
+/// Decoded `newStatements` subscription notification.
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct NewStatements {
+    /// Remote subscription id included in the notification.
+    pub remote_subscription_id: String,
+    /// SCALE-encoded signed statements carried by the notification.
+    pub statements: Vec<Vec<u8>>,
+    /// Optional server-side backlog count.
+    pub remaining: Option<u64>,
+}
+
+/// Topic filter flavor used by statement-store subscribe requests.
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum TopicFilterKind {
+    /// Require every listed topic to match.
+    MatchAll,
+    /// Accept any listed topic match.
+    MatchAny,
+}
+
+/// Parse a statement-store subscription result value.
+pub fn parse_new_statements_result(
+    remote_subscription_id: String,
+    result: &Value,
+) -> Result<NewStatements, StatementStoreParseError> {
+    if result.get("event").and_then(Value::as_str) != Some("newStatements") {
+        return Err(StatementStoreParseError::Malformed(
+            "result is not a newStatements event".to_string(),
+        ));
+    }
+    let data = result
+        .get("data")
+        .ok_or_else(|| StatementStoreParseError::Malformed("missing data".to_string()))?;
+    let statement_values = data
+        .get("statements")
+        .and_then(Value::as_array)
+        .ok_or_else(|| StatementStoreParseError::Malformed("missing statements".to_string()))?;
+    let statements = statement_values
+        .iter()
+        .map(|value| {
+            let Some(hex) = value.as_str() else {
+                return Err(StatementStoreParseError::Malformed(
+                    "statement is not a hex string".to_string(),
+                ));
+            };
+            decode_hex(hex)
+        })
+        .collect::<Result<Vec<_>, _>>()?;
+    let remaining = data
+        .get("remaining")
+        .map(|value| {
+            value.as_u64().ok_or_else(|| {
+                StatementStoreParseError::Malformed("remaining is not an integer".to_string())
+            })
+        })
+        .transpose()?;
+
+    Ok(NewStatements {
+        remote_subscription_id,
+        statements,
+        remaining,
+    })
+}
+
+fn decode_hex(value: &str) -> Result<Vec<u8>, StatementStoreParseError> {
+    hex::decode(value.strip_prefix("0x").unwrap_or(value))
+        .map_err(|error| StatementStoreParseError::InvalidStatementHex(error.to_string()))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn parses_dotli_sdk_new_statements_result() {
+        let result = serde_json::json!({
+            "event": "newStatements",
+            "data": {
+                "statements": ["0xdeadbeef", "0xcafe"],
+                "remaining": 0,
+            },
+        });
+
+        assert_eq!(
+            parse_new_statements_result("remote-sub".to_string(), &result).unwrap(),
+            NewStatements {
+                remote_subscription_id: "remote-sub".to_string(),
+                statements: vec![vec![0xde, 0xad, 0xbe, 0xef], vec![0xca, 0xfe]],
+                remaining: Some(0),
+            }
+        );
+    }
+}