feat(shared): CLI Error Types

Cargo.toml

@@ -215,6 +215,9 @@ vergen = "9.0.6"
 vergen-git2 = "1.0.7"
 clap = { version = "4.5.53", features = ["derive", "env", "string"] }
 
+# Metrics
+metrics-exporter-prometheus = { version = "0.18.1", default-features = false }
+
 # misc
 url = "2.5.7"
 lru = "0.16.2"

crates/shared/cli-utils/Cargo.toml

@@ -17,6 +17,8 @@ tokio = { workspace = true, features = ["full"] }
 eyre.workspace = true
 clap = { workspace = true, features = ["derive"] }
 tracing.workspace = true
+thiserror.workspace = true
+metrics-exporter-prometheus = { workspace = true, features = ["http-listener"] }
 
 [target.'cfg(unix)'.dependencies]
 libc = "0.2"

crates/shared/cli-utils/src/errors.rs

@@ -0,0 +1,26 @@
+//! Error types for CLI utilities.
+
+use thiserror::Error;
+
+/// Errors that can occur in CLI operations.
+#[derive(Error, Debug)]
+pub enum CliError {
+    /// Error when no chain config is found for the given chain ID.
+    #[error("No chain config found for chain ID: {0}")]
+    ChainConfigNotFound(u64),
+
+    /// Error when no roles are found for the given chain ID.
+    #[error("No roles found for chain ID: {0}")]
+    RolesNotFound(u64),
+
+    /// Error when no unsafe block signer is found for the given chain ID.
+    #[error("No unsafe block signer found for chain ID: {0}")]
+    UnsafeBlockSignerNotFound(u64),
+
+    /// Error initializing metrics.
+    #[error("Failed to initialize metrics")]
+    MetricsInitialization(#[from] metrics_exporter_prometheus::BuildError),
+}
+
+/// Type alias for CLI results.
+pub type CliResult<T> = Result<T, CliError>;

crates/shared/cli-utils/src/lib.rs

@@ -9,6 +9,9 @@ pub use sigsegv::SigsegvHandler;
 mod backtrace;
 pub use backtrace::Backtracing;
 
+mod errors;
+pub use errors::{CliError, CliResult};
+
 mod args;
 pub use args::GlobalArgs;