Orchestratord OIDC testing and dyncfg-file Option<String> support

ci/nightly/pipeline.template.yml

@@ -2365,6 +2365,20 @@ steps:
         agents:
           queue: hetzner-aarch64-16cpu-32gb
 
+      - id: orchestratord-oidc-auth
+        label: Orchestratord OIDC auth end-to-end
+        artifact_paths: ["mz_debug_*.zip"]
+        depends_on: devel-docker-tags
+        timeout_in_minutes: 60
+        plugins:
+          - ./ci/plugins/mzcompose:
+              composition: orchestratord
+              run: oidc-auth
+              args: [--recreate-cluster]
+              ci-builder: stable
+        agents:
+          queue: hetzner-aarch64-16cpu-32gb
+
   - id: emulator
     label: Materialize Emulator
     depends_on: build-aarch64

src/dyncfg-file/src/lib.rs

@@ -176,6 +176,10 @@ fn json_to_config_val(json: &JsonValue, template: &ConfigVal) -> Result<ConfigVa
             v.as_f64().ok_or_else(|| anyhow::anyhow!("not an f64"))?,
         )),
         (ConfigVal::String(_), JsonValue::String(v)) => Ok(ConfigVal::String(v.clone())),
+        (ConfigVal::OptString(_), JsonValue::Null) => Ok(ConfigVal::OptString(None)),
+        (ConfigVal::OptString(_), JsonValue::String(v)) => {
+            Ok(ConfigVal::OptString(Some(v.clone())))
+        }
         (ConfigVal::Duration(_), JsonValue::String(v)) => {
             Ok(ConfigVal::Duration(humantime::parse_duration(v)?))
         }
@@ -240,4 +244,42 @@ mod tests {
         assert_eq!(BOOL_CONFIG.get(&set), false);
         assert_eq!(STRING_CONFIG.get(&set), "modified");
     }
+
+    #[mz_ore::test(tokio::test)]
+    async fn test_file_sync_opt_string() {
+        const OPT_STRING_CONFIG: Config<Option<&str>> =
+            Config::new("test_opt_string", None, "A test optional string config");
+        let set = ConfigSet::default().add(&OPT_STRING_CONFIG);
+
+        let mut config_file = tempfile::NamedTempFile::new().unwrap();
+        config_file
+            .write_all(b"{\"test_opt_string\": \"hello\"}")
+            .unwrap();
+        sync_file_to_configset(
+            set.clone(),
+            &config_file,
+            Duration::from_secs(1),
+            None,
+            |_, _| {},
+        )
+        .await
+        .unwrap();
+        assert_eq!(OPT_STRING_CONFIG.get(&set), Some("hello".to_string()));
+
+        // null clears the value back to None
+        let mut config_file = tempfile::NamedTempFile::new().unwrap();
+        config_file
+            .write_all(b"{\"test_opt_string\": null}")
+            .unwrap();
+        sync_file_to_configset(
+            set.clone(),
+            &config_file,
+            Duration::from_secs(1),
+            None,
+            |_, _| {},
+        )
+        .await
+        .unwrap();
+        assert_eq!(OPT_STRING_CONFIG.get(&set), None);
+    }
 }