fix: config empty values unset, drop adapter from_vars

crates/adapters/nats/src/config.rs

@@ -15,40 +15,23 @@ pub struct NatsConfig {
 
 impl NatsConfig {
     pub fn from_config(config: &::config::NatsConfig) -> anyhow::Result<Self> {
-        Self::from_vars(
-            config.url.as_deref(),
-            Some(&config.mode),
-            Some(&config.subject_prefix),
-            Some(&config.stream_name),
-            Some(&config.consumer_name),
-        )
-    }
+        let url = config
+            .url
+            .clone()
+            .ok_or_else(|| anyhow::anyhow!("NATS_URL is not set"))?;
 
-    pub(crate) fn from_vars(
-        url: Option<&str>,
-        mode: Option<&str>,
-        subject_prefix: Option<&str>,
-        stream_name: Option<&str>,
-        consumer_name: Option<&str>,
-    ) -> anyhow::Result<Self> {
-        let url = url.ok_or_else(|| anyhow::anyhow!("NATS_URL is not set"))?;
-
-        let mode = match mode.unwrap_or("jetstream") {
+        let mode = match config.mode.as_str() {
             "core" => NatsMode::Core,
             "jetstream" => NatsMode::JetStream,
             other => anyhow::bail!("unknown NATS_MODE: {other}"),
         };
 
-        let subject_prefix = subject_prefix.unwrap_or("movies-diary.events").to_string();
-        let stream_name = stream_name.unwrap_or("MOVIES_DIARY_EVENTS").to_string();
-        let consumer_name = consumer_name.unwrap_or("worker").to_string();
-
         Ok(Self {
-            url: url.to_string(),
+            url,
             mode,
-            subject_prefix,
-            stream_name,
-            consumer_name,
+            subject_prefix: config.subject_prefix.clone(),
+            stream_name: config.stream_name.clone(),
+            consumer_name: config.consumer_name.clone(),
         })
     }
 }