Merge pull request #2633 from input-output-hk/dlachaume/2619/client-era-support

feat: add support for Mithril era transition in clients

Author: dlachaume

CHANGELOG.md

@@ -27,6 +27,8 @@ As a minor extension, we have adopted a slightly different versioning convention
 
 - Add pre-built Linux ARM binaries in the distribution for the signer, client CLI, and aggregator.
 
+- Support for Mithril era transition in the client library, CLI and WASM.
+
 - **UNSTABLE** :
   - Support for DMQ signature publisher in the signer and signature consumer in the aggregator.
 

Cargo.lock

@@ -92,3 +92,7 @@ sequenceDiagram
     Chain->>Old Node: Era change at Epoch XX
     Old Node->>User: 💀 unsupported Era, quit.
 ```
+
+### Client-side era awareness
+
+The Mithril clients do not have access to a Cardano node and therefore can not read the Era Activation Markers stored on chain. As a consequence, they rely on the current era run by the aggregator, by using the era advertised by its `/status` route.

docs/website/adr/004-mithril-network-update-strategy.md

@@ -1,6 +1,6 @@
 [package]
 name = "mithril-build-script"
-version = "0.2.24"
+version = "0.2.25"
 description = "A toolbox for Mithril crates build scripts"
 authors = { workspace = true }
 edition = { workspace = true }

docs/website/root/manual/develop/nodes/mithril-client.md

@@ -14,6 +14,8 @@ pub type FileContent = String;
 /// of the fake aggregator.
 #[derive(Debug, Default)]
 pub struct FakeAggregatorData {
+    status: FileContent,
+
     epoch_settings: FileContent,
 
     certificates_list: FileContent,
@@ -50,6 +52,9 @@ impl FakeAggregatorData {
             });
 
             match filename.as_str() {
+                "status.json" => {
+                    data.status = file_content;
+                }
                 "epoch-settings.json" => {
                     data.epoch_settings = file_content;
                 }
@@ -155,6 +160,7 @@ impl FakeAggregatorData {
     pub fn generate_code_for_all_data(self) -> String {
         Self::assemble_code(
             &[
+                generate_list_getter("status", self.status),
                 generate_list_getter("epoch_settings", self.epoch_settings),
                 generate_ids_array(
                     "snapshot_digests",

examples/client-wasm-nodejs/package-lock.json

@@ -1,6 +1,6 @@
 [package]
 name = "mithril-client-cli"
-version = "0.12.20"
+version = "0.12.21"
 description = "A Mithril Client"
 authors = { workspace = true }
 edition = { workspace = true }

examples/client-wasm-web/package-lock.json

@@ -12,21 +12,21 @@ pub mod tools;
 
 pub use deprecation::{DeprecatedCommand, Deprecation};
 
+use std::sync::Arc;
+
 use mithril_client::{ClientBuilder, MithrilResult};
 
-use crate::configuration::ConfigParameters;
+use crate::{configuration::ConfigParameters, utils::ForcedEraFetcher};
 
 const CLIENT_TYPE_CLI: &str = "CLI";
 
 pub(crate) fn client_builder(params: &ConfigParameters) -> MithrilResult<ClientBuilder> {
     let builder = ClientBuilder::aggregator(
         &params.require("aggregator_endpoint")?,
         &params.require("genesis_verification_key")?,
-    )
-    .with_origin_tag(params.get("origin_tag"))
-    .with_client_type(Some(CLIENT_TYPE_CLI.to_string()));
+    );
 
-    Ok(builder)
+    Ok(finalize_builder_config(builder, params))
 }
 
 pub(crate) fn client_builder_with_fallback_genesis_key(
@@ -44,9 +44,19 @@ pub(crate) fn client_builder_with_fallback_genesis_key(
             "genesis_verification_key",
             fallback_genesis_verification_key,
         ),
-    )
-    .with_origin_tag(params.get("origin_tag"))
-    .with_client_type(Some(CLIENT_TYPE_CLI.to_string()));
+    );
+
+    Ok(finalize_builder_config(builder, params))
+}
+
+fn finalize_builder_config(mut builder: ClientBuilder, params: &ConfigParameters) -> ClientBuilder {
+    builder = builder
+        .with_origin_tag(params.get("origin_tag"))
+        .with_client_type(Some(CLIENT_TYPE_CLI.to_string()));
+
+    if let Some(era) = params.get("era") {
+        builder = builder.with_era_fetcher(Arc::new(ForcedEraFetcher::new(era.to_string())));
+    }
 
-    Ok(builder)
+    builder
 }