Share validated source-window cohorts for derived maintenance

control_plane/src/physical/compiler.rs

@@ -1239,18 +1239,18 @@ impl PhysicalCompiler {
                                 query_id: query.query_id.clone(),
                                 reason: "derived source config missing".into(),
                             })?;
-                    if runtime_materialization.window_size != source_config.window_size
-                        || runtime_materialization.slide_interval != source_config.slide_interval
-                        || runtime_materialization.pane_origin_ms != source_config.pane_origin_ms
-                        || runtime_materialization.window_size
-                            != runtime_materialization.slide_interval
-                        || runtime_materialization.stored_window_ms()
-                            != source_config.stored_window_ms()
-                        || source_config.stored_window_ms()
-                            != source_config.window_size.saturating_mul(1_000)
+                    asap_types::precompute_plan::validated_source_window_cohort(
+                        &runtime_materialization,
+                        &[source_config],
+                    )
+                    .map_err(|error| CompileError::Query {
+                        query_id: query.query_id.clone(),
+                        reason: error.to_string(),
+                    })?;
+                    if runtime_materialization.window_size != runtime_materialization.slide_interval
                     {
                         return Err(CompileError::Query { query_id: query.query_id.clone(),
-                            reason: "immutable scalar composition requires matching full nonoverlapping windows".into() });
+                            reason: "immutable scalar composition runtime requires nonoverlapping windows".into() });
                     }
                     let SummaryExpr::SummaryAgg { child, .. } = &selected.node.expr else {
                         unreachable!()

crates/asap_types/src/precompute_plan.rs

@@ -9,6 +9,55 @@ use serde::{Deserialize, Serialize};
 use std::collections::{BTreeMap, BTreeSet, HashMap};
 use thiserror::Error;
 
+/// Validate the physical windows consumed by one derived input program.
+/// This returns the existing source definitions, not a second serialized
+/// contract. It does not prove completion or authorize runtime execution.
+/// Full-window sliding is lossless here; pane merging requires a separate
+/// explicit operator and is deliberately not inferred from window sizes.
+pub fn validated_source_window_cohort<'a>(
+    target: &crate::PrecomputeMaterialization,
+    sources: &[&'a crate::PrecomputeMaterialization],
+) -> Result<Vec<&'a crate::PrecomputeMaterialization>, PrecomputePlanError> {
+    let invalid = || {
+        PrecomputePlanError::CatalogContract(
+            "derived inputs require matching explicit full stored windows".into(),
+        )
+    };
+    let full_ms = target.window_size.checked_mul(1000).ok_or_else(invalid)?;
+    if sources.is_empty()
+        || full_ms == 0
+        || target.slide_interval == 0
+        || target.slide_interval > target.window_size
+        || (target.slide_interval < target.window_size && target.pane_origin_ms.is_none())
+        || target.stored_window_ms() != full_ms
+        || (target.slide_interval < target.window_size
+            && !matches!(
+                target.window_layout,
+                crate::WindowMaterializationLayout::FullWindow
+            ))
+    {
+        return Err(invalid());
+    }
+    let mut identities = BTreeSet::new();
+    for source in sources {
+        if source.derived_input.is_some()
+            || !identities.insert(source.policy_fingerprint())
+            || source.window_size != target.window_size
+            || source.slide_interval != target.slide_interval
+            || source.pane_origin_ms != target.pane_origin_ms
+            || source.stored_window_ms() != full_ms
+            || (source.slide_interval < source.window_size
+                && !matches!(
+                    source.window_layout,
+                    crate::WindowMaterializationLayout::FullWindow
+                ))
+        {
+            return Err(invalid());
+        }
+    }
+    Ok(sources.to_vec())
+}
+
 pub const BACKEND_COMPAT: &str = "asap-query-backend.v1";
 
 #[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq)]
@@ -381,14 +430,11 @@ impl PrecomputePlan {
                 .iter()
                 .find(|candidate| candidate.policy_fingerprint() == source_id.fingerprint())
                 .ok_or_else(invalid)?;
-            if source.derived_input.is_some()
-                || source.window_size != config.window_size
-                || source.slide_interval != config.slide_interval
-                || source.window_size != source.slide_interval
-                || source.pane_origin_ms != config.pane_origin_ms
-                || source.stored_window_ms() != config.stored_window_ms()
-                || source.window_size.checked_mul(1000) != Some(source.stored_window_ms())
-            {
+            validated_source_window_cohort(config, &[source])?;
+            // Current installed runtime capability remains nonoverlapping.
+            // The shared cohort contract also describes explicit full-window
+            // sliding for consumers which separately prove its completion.
+            if source.window_size != source.slide_interval {
                 return Err(invalid());
             }
             let mut matched = false;
@@ -700,3 +746,54 @@ pub(crate) fn state_encodings(family: &SummaryFamilyType) -> Vec<StateEncoding>
         _ => Vec::new(),
     }
 }
+
+#[cfg(test)]
+mod source_window_cohort_tests {
+    use super::*;
+    fn full_window() -> crate::PrecomputeMaterialization {
+        serde_json::from_value(serde_json::json!({
+            "aggregation_type":"Sum", "aggregation_sub_type":"", "parameters":{},
+            "grouping_labels":{"labels":[]}, "aggregated_labels":{"labels":[]},
+            "rollup_labels":{"labels":[]}, "original_yaml":"",
+            "window_size":60, "slide_interval":10, "window_type":"sliding",
+            "window_layout":{"kind":"full_window"}, "pane_origin_ms":0,
+            "spatial_filter":"", "spatial_filter_normalized":"", "metric":"m",
+            "num_aggregates_to_retain":null, "table_name":null, "value_projection":null
+        }))
+        .unwrap()
+    }
+    #[test]
+    fn full_sliding_cohort_preserves_explicit_windows_and_identity() {
+        let target = full_window();
+        let source = full_window();
+        let mut missing_origin = source.clone();
+        missing_origin.pane_origin_ms = None;
+        assert!(validated_source_window_cohort(&missing_origin, &[&missing_origin]).is_err());
+        missing_origin.slide_interval = missing_origin.window_size;
+        assert!(validated_source_window_cohort(&missing_origin, &[&missing_origin]).is_ok());
+        let result = validated_source_window_cohort(&target, &[&source]).unwrap();
+        assert!(std::ptr::eq(result[0], &source));
+        let mut other = source.clone();
+        other.metric = "other".into();
+        assert_eq!(
+            validated_source_window_cohort(&target, &[&source, &other])
+                .unwrap()
+                .len(),
+            2
+        );
+        assert!(validated_source_window_cohort(&target, &[&source, &source]).is_err());
+        for mutation in 0..3 {
+            let mut changed = source.clone();
+            match mutation {
+                0 => changed.pane_origin_ms = Some(1),
+                1 => changed.slide_interval = 20,
+                _ => {
+                    changed.window_layout =
+                        crate::WindowMaterializationLayout::Pane { pane_secs: 10 }
+                }
+            }
+            assert_ne!(source.policy_fingerprint(), changed.policy_fingerprint());
+            assert!(validated_source_window_cohort(&target, &[&changed]).is_err());
+        }
+    }
+}