v0.2.9-pre.004

crates/ksp-onchain-transport-lib/src/grpc_subscribe.rs

@@ -0,0 +1,562 @@
+// file: crates/ksp-onchain-transport-lib/src/grpc_subscribe.rs
+// version: 1
+
+const MAX_GRPC_SUBSCRIBE_DATA_SLICE_COUNT: usize = 128;
+const MAX_GRPC_SUBSCRIBE_DATA_SLICE_LENGTH_BYTES: u64 = 64 * 1024 * 1024;
+const MAX_GRPC_SUBSCRIBE_FILTER_GROUP_COUNT: usize = 1_024;
+const MAX_GRPC_SUBSCRIBE_FILTER_NAME_LENGTH_BYTES: usize = 128;
+
+/// Validated logical filter name used by the standard Yellowstone `SubscribeRequest` maps.
+///
+/// Filter names are returned by Yellowstone in update envelopes. KSP therefore keeps them as typed public data, but omits their text from `Debug` so routine
+/// diagnostics cannot accidentally disclose caller-defined labels.
+#[derive(Clone, Eq, Hash, Ord, PartialEq, PartialOrd)]
+pub struct YellowstoneSubscribeFilterName {
+    value: std::string::String,
+}
+
+impl YellowstoneSubscribeFilterName {
+    /// Validates one provider-neutral Yellowstone filter-group name.
+    pub fn new(value: impl std::convert::Into<std::string::String>) -> ksp_core_lib::Result<Self> {
+        let value = value.into();
+        if value.is_empty() || value.len() > MAX_GRPC_SUBSCRIBE_FILTER_NAME_LENGTH_BYTES || value.trim() != value || value.chars().any(char::is_control) {
+            return std::result::Result::Err(
+                ksp_core_lib::Error::new(crate::ERROR_CODE_INVALID_RPC_PARAMETERS, "Yellowstone subscribe filter name is invalid")
+                    .with_context("field", "grpc_subscribe.filter_name"),
+            );
+        }
+        return std::result::Result::Ok(Self { value });
+    }
+
+    /// Returns the validated filter name text.
+    #[must_use]
+    pub fn as_str(&self) -> &str {
+        return self.value.as_str();
+    }
+}
+
+impl std::fmt::Debug for YellowstoneSubscribeFilterName {
+    fn fmt(&self, formatter: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        return formatter.write_str("YellowstoneSubscribeFilterName(<redacted>)");
+    }
+}
+
+/// One standard Yellowstone account-data slice applied to subscribed account payloads.
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
+pub struct YellowstoneAccountsDataSlice {
+    offset: u64,
+    length: u64,
+}
+
+impl YellowstoneAccountsDataSlice {
+    /// Creates and validates one account-data slice.
+    pub fn new(offset: u64, length: u64) -> ksp_core_lib::Result<Self> {
+        if length > MAX_GRPC_SUBSCRIBE_DATA_SLICE_LENGTH_BYTES || offset.checked_add(length).is_none() {
+            return std::result::Result::Err(
+                ksp_core_lib::Error::new(crate::ERROR_CODE_INVALID_RPC_PARAMETERS, "Yellowstone account-data slice exceeds KSP bounds")
+                    .with_context("field", "grpc_subscribe.accounts_data_slice"),
+            );
+        }
+        return std::result::Result::Ok(Self { offset, length });
+    }
+
+    /// Returns the byte offset.
+    #[must_use]
+    pub const fn offset(self) -> u64 {
+        return self.offset;
+    }
+
+    /// Returns the requested byte length.
+    #[must_use]
+    pub const fn length(self) -> u64 {
+        return self.length;
+    }
+
+    fn to_wire(self) -> yellowstone_grpc_proto::geyser::SubscribeRequestAccountsDataSlice {
+        return yellowstone_grpc_proto::geyser::SubscribeRequestAccountsDataSlice { offset: self.offset, length: self.length };
+    }
+}
+
+/// Optional ping mutation carried inside the standard Yellowstone subscribe stream.
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
+pub struct YellowstoneSubscribePing {
+    id: i32,
+}
+
+impl YellowstoneSubscribePing {
+    /// Creates one subscribe-stream ping request.
+    #[must_use]
+    pub const fn new(id: i32) -> Self {
+        return Self { id };
+    }
+
+    /// Returns the exact ping identifier carried on the wire.
+    #[must_use]
+    pub const fn id(self) -> i32 {
+        return self.id;
+    }
+
+    fn to_wire(self) -> yellowstone_grpc_proto::geyser::SubscribeRequestPing {
+        return yellowstone_grpc_proto::geyser::SubscribeRequestPing { id: self.id };
+    }
+}
+
+/// Account-family filter-group shell for the standard Yellowstone subscribe surface.
+///
+/// `0.2.9-pre.004` intentionally materializes only the top-level map contract. Account selectors and account-specific filter oneofs are added by `pre.005`.
+#[derive(Clone, Debug, Default, Eq, PartialEq)]
+pub struct YellowstoneSubscribeAccountFilter {
+    _private: (),
+}
+
+impl YellowstoneSubscribeAccountFilter {
+    /// Creates an empty account filter group.
+    #[must_use]
+    pub const fn new() -> Self {
+        return Self { _private: () };
+    }
+
+    fn to_wire(&self) -> yellowstone_grpc_proto::geyser::SubscribeRequestFilterAccounts {
+        return yellowstone_grpc_proto::geyser::SubscribeRequestFilterAccounts::default();
+    }
+}
+
+/// Slot-family filter-group shell for the standard Yellowstone subscribe surface.
+///
+/// Slot optional flags and update decoding are added by `0.2.9-pre.005`.
+#[derive(Clone, Debug, Default, Eq, PartialEq)]
+pub struct YellowstoneSubscribeSlotFilter {
+    _private: (),
+}
+
+impl YellowstoneSubscribeSlotFilter {
+    /// Creates an empty slot filter group.
+    #[must_use]
+    pub const fn new() -> Self {
+        return Self { _private: () };
+    }
+
+    fn to_wire(&self) -> yellowstone_grpc_proto::geyser::SubscribeRequestFilterSlots {
+        return yellowstone_grpc_proto::geyser::SubscribeRequestFilterSlots::default();
+    }
+}
+
+/// Transaction-family filter-group shell shared by `transactions` and `transactions_status`.
+///
+/// Transaction selectors, Cuckoo filters and token-account expansion are added by `0.2.9-pre.006`.
+#[derive(Clone, Debug, Default, Eq, PartialEq)]
+pub struct YellowstoneSubscribeTransactionFilter {
+    _private: (),
+}
+
+impl YellowstoneSubscribeTransactionFilter {
+    /// Creates an empty transaction filter group.
+    #[must_use]
+    pub const fn new() -> Self {
+        return Self { _private: () };
+    }
+
+    fn to_wire(&self) -> yellowstone_grpc_proto::geyser::SubscribeRequestFilterTransactions {
+        return yellowstone_grpc_proto::geyser::SubscribeRequestFilterTransactions::default();
+    }
+}
+
+/// Block-family filter-group shell for the standard Yellowstone subscribe surface.
+///
+/// Block selectors, include flags and Cuckoo filters are added by `0.2.9-pre.007`.
+#[derive(Clone, Debug, Default, Eq, PartialEq)]
+pub struct YellowstoneSubscribeBlockFilter {
+    _private: (),
+}
+
+impl YellowstoneSubscribeBlockFilter {
+    /// Creates an empty block filter group.
+    #[must_use]
+    pub const fn new() -> Self {
+        return Self { _private: () };
+    }
+
+    fn to_wire(&self) -> yellowstone_grpc_proto::geyser::SubscribeRequestFilterBlocks {
+        return yellowstone_grpc_proto::geyser::SubscribeRequestFilterBlocks::default();
+    }
+}
+
+/// Named empty filter activating the standard Yellowstone `blocks_meta` family.
+#[derive(Clone, Copy, Debug, Default, Eq, PartialEq)]
+pub struct YellowstoneSubscribeBlocksMetaFilter {
+    _private: (),
+}
+
+impl YellowstoneSubscribeBlocksMetaFilter {
+    /// Creates the empty marker filter.
+    #[must_use]
+    pub const fn new() -> Self {
+        return Self { _private: () };
+    }
+
+    fn to_wire(self) -> yellowstone_grpc_proto::geyser::SubscribeRequestFilterBlocksMeta {
+        return yellowstone_grpc_proto::geyser::SubscribeRequestFilterBlocksMeta::default();
+    }
+}
+
+/// Named empty filter activating the standard Yellowstone `entry` family.
+#[derive(Clone, Copy, Debug, Default, Eq, PartialEq)]
+pub struct YellowstoneSubscribeEntryFilter {
+    _private: (),
+}
+
+impl YellowstoneSubscribeEntryFilter {
+    /// Creates the empty marker filter.
+    #[must_use]
+    pub const fn new() -> Self {
+        return Self { _private: () };
+    }
+
+    fn to_wire(self) -> yellowstone_grpc_proto::geyser::SubscribeRequestFilterEntry {
+        return yellowstone_grpc_proto::geyser::SubscribeRequestFilterEntry::default();
+    }
+}
+
+/// Provider-neutral standard Yellowstone subscribe request owned by KSP.
+///
+/// The seven upstream maps are represented independently and retain named empty entries. An entirely empty map is the logical KSP representation of no active
+/// filter in that family; protobuf map encoding does not distinguish an omitted map from an empty map. Filter-group names are globally unique across all seven
+/// maps so the names echoed by `SubscribeUpdate.filters` remain unambiguous. `Debug` exposes only counts and common scalar options, never filter names or future
+/// filter payloads.
+#[derive(Clone, Eq, PartialEq)]
+pub struct YellowstoneSubscribeRequest {
+    accounts: std::collections::BTreeMap<crate::YellowstoneSubscribeFilterName, crate::YellowstoneSubscribeAccountFilter>,
+    slots: std::collections::BTreeMap<crate::YellowstoneSubscribeFilterName, crate::YellowstoneSubscribeSlotFilter>,
+    transactions: std::collections::BTreeMap<crate::YellowstoneSubscribeFilterName, crate::YellowstoneSubscribeTransactionFilter>,
+    transactions_status: std::collections::BTreeMap<crate::YellowstoneSubscribeFilterName, crate::YellowstoneSubscribeTransactionFilter>,
+    blocks: std::collections::BTreeMap<crate::YellowstoneSubscribeFilterName, crate::YellowstoneSubscribeBlockFilter>,
+    blocks_meta: std::collections::BTreeMap<crate::YellowstoneSubscribeFilterName, crate::YellowstoneSubscribeBlocksMetaFilter>,
+    entry: std::collections::BTreeMap<crate::YellowstoneSubscribeFilterName, crate::YellowstoneSubscribeEntryFilter>,
+    commitment: std::option::Option<crate::SolanaCommitment>,
+    accounts_data_slice: std::vec::Vec<crate::YellowstoneAccountsDataSlice>,
+    ping: std::option::Option<crate::YellowstoneSubscribePing>,
+    from_slot: std::option::Option<u64>,
+}
+
+impl YellowstoneSubscribeRequest {
+    /// Creates an empty subscribe request. Empty requests are valid because later bidi lifecycle code uses request mutations to clear filters or carry ping state.
+    #[must_use]
+    pub fn new() -> Self {
+        return Self {
+            accounts: std::collections::BTreeMap::new(),
+            slots: std::collections::BTreeMap::new(),
+            transactions: std::collections::BTreeMap::new(),
+            transactions_status: std::collections::BTreeMap::new(),
+            blocks: std::collections::BTreeMap::new(),
+            blocks_meta: std::collections::BTreeMap::new(),
+            entry: std::collections::BTreeMap::new(),
+            commitment: std::option::Option::None,
+            accounts_data_slice: std::vec::Vec::new(),
+            ping: std::option::Option::None,
+            from_slot: std::option::Option::None,
+        };
+    }
+
+    /// Inserts one named account filter group.
+    pub fn insert_account_filter(
+        &mut self,
+        name: crate::YellowstoneSubscribeFilterName,
+        filter: crate::YellowstoneSubscribeAccountFilter,
+    ) -> ksp_core_lib::Result<()> {
+        let validation = self.validate_new_filter_name(&name);
+        if let std::result::Result::Err(error) = validation {
+            return std::result::Result::Err(error);
+        }
+        self.accounts.insert(name, filter);
+        return std::result::Result::Ok(());
+    }
+
+    /// Inserts one named slot filter group.
+    pub fn insert_slot_filter(
+        &mut self,
+        name: crate::YellowstoneSubscribeFilterName,
+        filter: crate::YellowstoneSubscribeSlotFilter,
+    ) -> ksp_core_lib::Result<()> {
+        let validation = self.validate_new_filter_name(&name);
+        if let std::result::Result::Err(error) = validation {
+            return std::result::Result::Err(error);
+        }
+        self.slots.insert(name, filter);
+        return std::result::Result::Ok(());
+    }
+
+    /// Inserts one named transaction filter group.
+    pub fn insert_transaction_filter(
+        &mut self,
+        name: crate::YellowstoneSubscribeFilterName,
+        filter: crate::YellowstoneSubscribeTransactionFilter,
+    ) -> ksp_core_lib::Result<()> {
+        let validation = self.validate_new_filter_name(&name);
+        if let std::result::Result::Err(error) = validation {
+            return std::result::Result::Err(error);
+        }
+        self.transactions.insert(name, filter);
+        return std::result::Result::Ok(());
+    }
+
+    /// Inserts one named transaction-status filter group.
+    pub fn insert_transaction_status_filter(
+        &mut self,
+        name: crate::YellowstoneSubscribeFilterName,
+        filter: crate::YellowstoneSubscribeTransactionFilter,
+    ) -> ksp_core_lib::Result<()> {
+        let validation = self.validate_new_filter_name(&name);
+        if let std::result::Result::Err(error) = validation {
+            return std::result::Result::Err(error);
+        }
+        self.transactions_status.insert(name, filter);
+        return std::result::Result::Ok(());
+    }
+
+    /// Inserts one named block filter group.
+    pub fn insert_block_filter(
+        &mut self,
+        name: crate::YellowstoneSubscribeFilterName,
+        filter: crate::YellowstoneSubscribeBlockFilter,
+    ) -> ksp_core_lib::Result<()> {
+        let validation = self.validate_new_filter_name(&name);
+        if let std::result::Result::Err(error) = validation {
+            return std::result::Result::Err(error);
+        }
+        self.blocks.insert(name, filter);
+        return std::result::Result::Ok(());
+    }
+
+    /// Inserts one named empty `blocks_meta` filter group.
+    pub fn insert_blocks_meta_filter(
+        &mut self,
+        name: crate::YellowstoneSubscribeFilterName,
+        filter: crate::YellowstoneSubscribeBlocksMetaFilter,
+    ) -> ksp_core_lib::Result<()> {
+        let validation = self.validate_new_filter_name(&name);
+        if let std::result::Result::Err(error) = validation {
+            return std::result::Result::Err(error);
+        }
+        self.blocks_meta.insert(name, filter);
+        return std::result::Result::Ok(());
+    }
+
+    /// Inserts one named empty `entry` filter group.
+    pub fn insert_entry_filter(
+        &mut self,
+        name: crate::YellowstoneSubscribeFilterName,
+        filter: crate::YellowstoneSubscribeEntryFilter,
+    ) -> ksp_core_lib::Result<()> {
+        let validation = self.validate_new_filter_name(&name);
+        if let std::result::Result::Err(error) = validation {
+            return std::result::Result::Err(error);
+        }
+        self.entry.insert(name, filter);
+        return std::result::Result::Ok(());
+    }
+
+    /// Sets or clears the optional standard Yellowstone commitment.
+    pub fn set_commitment(&mut self, commitment: std::option::Option<crate::SolanaCommitment>) {
+        self.commitment = commitment;
+    }
+
+    /// Adds one validated account-data slice while preserving insertion order.
+    pub fn push_accounts_data_slice(&mut self, slice: crate::YellowstoneAccountsDataSlice) -> ksp_core_lib::Result<()> {
+        if self.accounts_data_slice.len() >= MAX_GRPC_SUBSCRIBE_DATA_SLICE_COUNT {
+            return std::result::Result::Err(
+                ksp_core_lib::Error::new(crate::ERROR_CODE_INVALID_RPC_PARAMETERS, "Yellowstone account-data slice count exceeds KSP bounds")
+                    .with_context("field", "grpc_subscribe.accounts_data_slice"),
+            );
+        }
+        self.accounts_data_slice.push(slice);
+        return std::result::Result::Ok(());
+    }
+
+    /// Sets or clears the optional subscribe-stream ping mutation.
+    pub fn set_ping(&mut self, ping: std::option::Option<crate::YellowstoneSubscribePing>) {
+        self.ping = ping;
+    }
+
+    /// Sets or clears the optional replay starting slot.
+    pub fn set_from_slot(&mut self, from_slot: std::option::Option<u64>) {
+        self.from_slot = from_slot;
+    }
+
+    /// Returns the number of active account filter groups.
+    #[must_use]
+    pub fn account_filter_count(&self) -> usize {
+        return self.accounts.len();
+    }
+
+    /// Returns the number of active slot filter groups.
+    #[must_use]
+    pub fn slot_filter_count(&self) -> usize {
+        return self.slots.len();
+    }
+
+    /// Returns the number of active transaction filter groups.
+    #[must_use]
+    pub fn transaction_filter_count(&self) -> usize {
+        return self.transactions.len();
+    }
+
+    /// Returns the number of active transaction-status filter groups.
+    #[must_use]
+    pub fn transaction_status_filter_count(&self) -> usize {
+        return self.transactions_status.len();
+    }
+
+    /// Returns the number of active block filter groups.
+    #[must_use]
+    pub fn block_filter_count(&self) -> usize {
+        return self.blocks.len();
+    }
+
+    /// Returns the number of active block-meta filter groups.
+    #[must_use]
+    pub fn blocks_meta_filter_count(&self) -> usize {
+        return self.blocks_meta.len();
+    }
+
+    /// Returns the number of active entry filter groups.
+    #[must_use]
+    pub fn entry_filter_count(&self) -> usize {
+        return self.entry.len();
+    }
+
+    /// Returns the optional request commitment.
+    #[must_use]
+    pub const fn commitment(&self) -> std::option::Option<crate::SolanaCommitment> {
+        return self.commitment;
+    }
+
+    /// Returns account-data slices in exact wire order.
+    #[must_use]
+    pub fn accounts_data_slices(&self) -> &[crate::YellowstoneAccountsDataSlice] {
+        return self.accounts_data_slice.as_slice();
+    }
+
+    /// Returns the optional subscribe-stream ping mutation.
+    #[must_use]
+    pub const fn ping(&self) -> std::option::Option<crate::YellowstoneSubscribePing> {
+        return self.ping;
+    }
+
+    /// Returns the optional replay starting slot.
+    #[must_use]
+    pub const fn from_slot(&self) -> std::option::Option<u64> {
+        return self.from_slot;
+    }
+
+    /// Validates all deterministic common subscribe-request bounds before any network I/O.
+    pub fn validate(&self) -> ksp_core_lib::Result<()> {
+        if self.total_filter_count() > MAX_GRPC_SUBSCRIBE_FILTER_GROUP_COUNT {
+            return std::result::Result::Err(
+                ksp_core_lib::Error::new(crate::ERROR_CODE_INVALID_RPC_PARAMETERS, "Yellowstone subscribe filter-group count exceeds KSP bounds")
+                    .with_context("field", "grpc_subscribe.filter_groups"),
+            );
+        }
+        if self.accounts_data_slice.len() > MAX_GRPC_SUBSCRIBE_DATA_SLICE_COUNT {
+            return std::result::Result::Err(
+                ksp_core_lib::Error::new(crate::ERROR_CODE_INVALID_RPC_PARAMETERS, "Yellowstone account-data slice count exceeds KSP bounds")
+                    .with_context("field", "grpc_subscribe.accounts_data_slice"),
+            );
+        }
+        return std::result::Result::Ok(());
+    }
+
+    fn to_wire(&self) -> ksp_core_lib::Result<yellowstone_grpc_proto::geyser::SubscribeRequest> {
+        let validation = self.validate();
+        if let std::result::Result::Err(error) = validation {
+            return std::result::Result::Err(error);
+        }
+        return std::result::Result::Ok(yellowstone_grpc_proto::geyser::SubscribeRequest {
+            accounts: self.accounts.iter().map(|(name, filter)| return (name.as_str().to_owned(), filter.to_wire())).collect(),
+            slots: self.slots.iter().map(|(name, filter)| return (name.as_str().to_owned(), filter.to_wire())).collect(),
+            transactions: self.transactions.iter().map(|(name, filter)| return (name.as_str().to_owned(), filter.to_wire())).collect(),
+            transactions_status: self.transactions_status.iter().map(|(name, filter)| return (name.as_str().to_owned(), filter.to_wire())).collect(),
+            blocks: self.blocks.iter().map(|(name, filter)| return (name.as_str().to_owned(), filter.to_wire())).collect(),
+            blocks_meta: self.blocks_meta.iter().map(|(name, filter)| return (name.as_str().to_owned(), (*filter).to_wire())).collect(),
+            entry: self.entry.iter().map(|(name, filter)| return (name.as_str().to_owned(), (*filter).to_wire())).collect(),
+            commitment: commitment_to_wire(self.commitment),
+            accounts_data_slice: self.accounts_data_slice.iter().copied().map(crate::YellowstoneAccountsDataSlice::to_wire).collect(),
+            ping: self.ping.map(crate::YellowstoneSubscribePing::to_wire),
+            from_slot: self.from_slot,
+        });
+    }
+
+    fn total_filter_count(&self) -> usize {
+        return self.accounts.len()
+            + self.slots.len()
+            + self.transactions.len()
+            + self.transactions_status.len()
+            + self.blocks.len()
+            + self.blocks_meta.len()
+            + self.entry.len();
+    }
+
+    fn contains_filter_name(&self, name: &crate::YellowstoneSubscribeFilterName) -> bool {
+        return self.accounts.contains_key(name)
+            || self.slots.contains_key(name)
+            || self.transactions.contains_key(name)
+            || self.transactions_status.contains_key(name)
+            || self.blocks.contains_key(name)
+            || self.blocks_meta.contains_key(name)
+            || self.entry.contains_key(name);
+    }
+
+    fn validate_new_filter_name(&self, name: &crate::YellowstoneSubscribeFilterName) -> ksp_core_lib::Result<()> {
+        if self.contains_filter_name(name) {
+            return std::result::Result::Err(
+                ksp_core_lib::Error::new(crate::ERROR_CODE_INVALID_RPC_PARAMETERS, "Yellowstone subscribe filter name must be globally unique")
+                    .with_context("field", "grpc_subscribe.filter_name"),
+            );
+        }
+        if self.total_filter_count() >= MAX_GRPC_SUBSCRIBE_FILTER_GROUP_COUNT {
+            return std::result::Result::Err(
+                ksp_core_lib::Error::new(crate::ERROR_CODE_INVALID_RPC_PARAMETERS, "Yellowstone subscribe filter-group count exceeds KSP bounds")
+                    .with_context("field", "grpc_subscribe.filter_groups"),
+            );
+        }
+        return std::result::Result::Ok(());
+    }
+}
+
+fn commitment_to_wire(commitment: std::option::Option<crate::SolanaCommitment>) -> std::option::Option<i32> {
+    return commitment.map(|value| {
+        return match value {
+            crate::SolanaCommitment::Processed => yellowstone_grpc_proto::geyser::CommitmentLevel::Processed as i32,
+            crate::SolanaCommitment::Confirmed => yellowstone_grpc_proto::geyser::CommitmentLevel::Confirmed as i32,
+            crate::SolanaCommitment::Finalized => yellowstone_grpc_proto::geyser::CommitmentLevel::Finalized as i32,
+        };
+    });
+}
+
+impl std::default::Default for YellowstoneSubscribeRequest {
+    fn default() -> Self {
+        return Self::new();
+    }
+}
+
+impl std::fmt::Debug for YellowstoneSubscribeRequest {
+    fn fmt(&self, formatter: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        return formatter
+            .debug_struct("YellowstoneSubscribeRequest")
+            .field("account_filter_count", &self.accounts.len())
+            .field("slot_filter_count", &self.slots.len())
+            .field("transaction_filter_count", &self.transactions.len())
+            .field("transaction_status_filter_count", &self.transactions_status.len())
+            .field("block_filter_count", &self.blocks.len())
+            .field("blocks_meta_filter_count", &self.blocks_meta.len())
+            .field("entry_filter_count", &self.entry.len())
+            .field("commitment", &self.commitment)
+            .field("accounts_data_slice_count", &self.accounts_data_slice.len())
+            .field("ping", &self.ping)
+            .field("from_slot", &self.from_slot)
+            .finish();
+    }
+}
+
+#[cfg(test)]
+#[path = "../unit_tests/grpc_subscribe.rs"]
+mod tests;