cleanup: resolve a few Rust warnings (#907)

Author: georgeh0

src/base/spec.rs

@@ -18,16 +18,6 @@ pub trait SpecFormatter {
     fn format(&self, mode: OutputMode) -> String;
 }
 
-#[derive(Debug, Clone, Serialize, Deserialize)]
-#[serde(tag = "kind")]
-pub enum SpecString {
-    /// The value comes from the environment variable.
-    Env(String),
-    /// The value is defined by the literal string.
-    #[serde(untagged)]
-    Literal(String),
-}
-
 pub type ScopeName = String;
 
 /// Used to identify a data field within a flow.

src/lib_context.rs

@@ -122,7 +122,7 @@ impl FlowContext {
 
     pub async fn use_execution_ctx(
         &self,
-    ) -> Result<tokio::sync::RwLockReadGuard<FlowExecutionContext>> {
+    ) -> Result<tokio::sync::RwLockReadGuard<'_, FlowExecutionContext>> {
         let execution_ctx = self.execution_ctx.read().await;
         if !execution_ctx.setup_change.is_up_to_date() {
             api_bail!(

src/utils/db.rs

@@ -1,32 +1,3 @@
-#[derive(Debug, Clone, PartialEq, Eq)]
-pub struct ValidIdentifier(pub String);
-
-impl TryFrom<String> for ValidIdentifier {
-    type Error = anyhow::Error;
-
-    fn try_from(s: String) -> Result<Self, Self::Error> {
-        if !s.is_empty() && s.chars().all(|c| c.is_alphanumeric() || c == '_') {
-            Ok(ValidIdentifier(s))
-        } else {
-            Err(anyhow::anyhow!("Invalid identifier: {s:?}"))
-        }
-    }
-}
-
-impl std::fmt::Display for ValidIdentifier {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        std::fmt::Display::fmt(&self.0, f)
-    }
-}
-
-impl std::ops::Deref for ValidIdentifier {
-    type Target = String;
-
-    fn deref(&self) -> &Self::Target {
-        &self.0
-    }
-}
-
 pub enum WriteAction {
     Insert,
     Update,