box flowmodule to reduce stack allocation of flowvalue

backend/windmill-api/src/flows.rs

@@ -955,7 +955,7 @@ mod tests {
                     continue_on_error: None,
                 },
             ],
-            failure_module: Some(FlowModule {
+            failure_module: Some(Box::new(FlowModule {
                 id: "d".to_string(),
                 value: FlowModuleValue::Script {
                     path: "test".to_string(),
@@ -977,7 +977,7 @@ mod tests {
                 priority: None,
                 delete_after_use: None,
                 continue_on_error: None,
-            }),
+            })),
             same_worker: false,
             concurrent_limit: None,
             concurrency_time_window_s: None,

backend/windmill-common/src/flows.rs

@@ -87,7 +87,7 @@ pub struct FlowValue {
     pub modules: Vec<FlowModule>,
     #[serde(skip_serializing_if = "Option::is_none")]
     #[serde(default)]
-    pub failure_module: Option<FlowModule>,
+    pub failure_module: Option<Box<FlowModule>>,
     #[serde(default)]
     #[serde(skip_serializing_if = "is_default")]
     pub same_worker: bool,

backend/windmill-worker/src/worker_flow.rs

@@ -931,7 +931,7 @@ fn get_module(flow_job: &QueuedJob, module_index: Option<usize>) -> Option<FlowM
             if let Some(module) = raw_flow.modules.get(i) {
                 Some(module.clone())
             } else {
-                raw_flow.failure_module
+                raw_flow.failure_module.map(|x| *x.clone())
             }
         } else {
             None
@@ -1674,7 +1674,7 @@ async fn push_next_flow_job<R: rsmq_async::RsmqConnection + Send + Sync + Clone>
     let mut module: &FlowModule = flow
         .modules
         .get(i)
-        .or_else(|| flow.failure_module.as_ref())
+        .or_else(|| flow.failure_module.as_deref())
         .with_context(|| format!("no module at index {}", status.step))?;
 
     let current_id = &module.id;