Create SignedEntityType entity

mithril-common/src/entities/mod.rs

@@ -10,6 +10,7 @@ mod epoch_settings;
 mod http_server_error;
 mod protocol_message;
 mod protocol_parameters;
+mod signed_entity_type;
 mod signer;
 mod single_signatures;
 mod snapshot;
@@ -25,6 +26,7 @@ pub use epoch_settings::EpochSettings;
 pub use http_server_error::{ClientError, InternalServerError};
 pub use protocol_message::{ProtocolMessage, ProtocolMessagePartKey, ProtocolMessagePartValue};
 pub use protocol_parameters::ProtocolParameters;
+pub use signed_entity_type::SignedEntityType;
 pub use signer::{Signer, SignerWithStake};
 pub use single_signatures::SingleSignatures;
 pub use snapshot::Snapshot;

mithril-common/src/entities/signed_entity_type.rs

@@ -0,0 +1,44 @@
+use strum::IntoEnumIterator;
+use strum_macros::{Display, EnumIter, EnumString, FromRepr};
+
+/// The signed entity type that represents a type of data signed by the Mithril protocol
+/// Note: Each variant of this enum must be associated to an entry in the `signed_entity_type` tables of the signer/aggregator nodes.
+///       The variant are identified by their discriminant (i.e. index in the enum), thus the modification of this type should only ever consist of appending new variants.
+#[derive(Display, FromRepr, EnumString, EnumIter, Debug, Clone, Copy, PartialEq, Eq)]
+#[strum(serialize_all = "PascalCase")]
+pub enum SignedEntityType {
+    /// Mithril stake distribution
+    MithrilStakeDistribution,
+
+    /// Cardano Stake Distribution
+    CardanoStakeDistribution,
+
+    /// Full Cardano Immutable Files
+    CardanoImmutableFilesFull,
+}
+
+impl SignedEntityType {
+    /// Retrieve the list of entity types
+    pub fn entity_types() -> Vec<Self> {
+        Self::iter().collect()
+    }
+
+    /// Retrieve a dummy enty (for test only)
+    #[cfg(any(test, feature = "test_only"))]
+    pub fn dummy() -> Self {
+        Self::entity_types().first().unwrap().to_owned()
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn from_repr() {
+        let supported_entity_type = SignedEntityType::from_repr(SignedEntityType::dummy() as usize)
+            .expect("This signed entity type should support conversion from representation.");
+
+        assert_eq!(SignedEntityType::dummy(), supported_entity_type);
+    }
+}