Merge pull request #13 from cardmagic/agent/fix-batch-revision-races

fix: coordinate batch refreshes by revision

Author: cardmagic

CHANGELOG.md

@@ -1,5 +1,15 @@
 # Changelog
 
+## 0.7.3 - 2026-08-09
+
+- Coordinate batched component refreshes by revision as well as scope and batch
+  name. Invalidations for one revision arrive as separate WebSocket messages, so
+  the microtask merge could not see them all, and each request aborted the one
+  before it. Only the last component updated. Same-revision requests now run
+  alongside each other and every frame is applied; only a strictly newer
+  revision supersedes an in-flight request. Frames already applied at a revision
+  are not applied twice.
+
 ## 0.7.2 - 2026-08-09
 
 - Render batched component partials as HTML regardless of the request format.

Gemfile.lock

@@ -1,7 +1,7 @@
 PATH
   remote: .
   specs:
-    solid_objects (0.7.2)
+    solid_objects (0.7.3)
       actioncable (>= 8.0)
       actionpack (>= 8.0)
       actionview (>= 8.0)
@@ -373,7 +373,7 @@ CHECKSUMS
   rubocop-rails-omakase (1.1.0) sha256=2af73ac8ee5852de2919abbd2618af9c15c19b512c4cfc1f9a5d3b6ef009109d
   ruby-progressbar (1.13.0) sha256=80fc9c47a9b640d6834e0dc7b3c94c9df37f08cb072b7761e4a71e22cff29b33
   securerandom (0.4.1) sha256=cc5193d414a4341b6e225f0cb4446aceca8e50d5e1888743fac16987638ea0b1
-  solid_objects (0.7.2)
+  solid_objects (0.7.3)
   sqlite3 (2.9.5-aarch64-linux-gnu) sha256=78075b6337d3d182c6d2b4691049ed45cd220826160c9ea18946bf6a1de200dc
   sqlite3 (2.9.5-aarch64-linux-musl) sha256=18c801185deb4adc01ddb281e8f672a39e3d1729979ca91e39439cd3eac0402d
   sqlite3 (2.9.5-arm-linux-gnu) sha256=1bdfca0c7d63998c60b0f4a8e3c8df2d33800ccc4abd2d612eddbbbc92a4c48b

app/assets/javascripts/solid_objects/component_batch_refresh.js

@@ -1,5 +1,7 @@
 const pendingBatches = new Map()
 const activeBatches = new Map()
+const appliedRevisions = new Map()
+let requestSequence = 0
 
 class SolidObjectsBatchRefreshElement extends HTMLElement {
   connectedCallback() {
@@ -34,18 +36,26 @@ class SolidObjectsBatchRefreshElement extends HTMLElement {
     pendingBatches.set(key, merged)
     queueMicrotask(() => {
       pendingBatches.delete(key)
-      requestBatch(group, batch, merged.sources)
+      requestBatch(group, batch, revision, merged.sources)
     })
     this.remove()
   }
 }
 
-async function requestBatch(group, batch, sources) {
-  const previous = activeBatches.get(group)
-  previous?.abort()
-
+// Invalidations for one revision arrive in separate WebSocket messages, so the
+// microtask merge cannot see them all. Requests are tracked per revision and a
+// request is only cancelled by a strictly newer one; same-revision requests run
+// alongside each other and every frame is applied.
+async function requestBatch(group, batch, revision, sources) {
+  const parsed = parseRevision(revision)
+  supersedeOlderRequests(group, parsed)
+
+  // Same-revision requests run concurrently, so each needs its own entry.
+  // Sharing one key per revision would leave all but the last untracked and
+  // therefore impossible to supersede.
+  const key = `${group}:${revision}:${(requestSequence += 1)}`
   const controller = new AbortController()
-  activeBatches.set(group, controller)
+  activeBatches.set(key, { controller, group, revision: parsed })
 
   try {
     const url = mergedUrl(sources)
@@ -68,10 +78,29 @@ async function requestBatch(group, batch, sources) {
   } catch (error) {
     if (error.name !== "AbortError") dispatchBatchError(batch, "request_failed")
   } finally {
-    if (activeBatches.get(group) === controller) activeBatches.delete(group)
+    if (activeBatches.get(key)?.controller === controller) activeBatches.delete(key)
   }
 }
 
+function supersedeOlderRequests(group, revision) {
+  if (!revision) return
+
+  activeBatches.forEach((entry, key) => {
+    if (entry.group !== group) return
+    if (!olderRevision(entry.revision, revision)) return
+
+    entry.controller.abort()
+    activeBatches.delete(key)
+  })
+}
+
+function olderRevision(candidate, current) {
+  if (!candidate || !current) return false
+
+  return candidate[0] < current[0] ||
+    (candidate[0] === current[0] && candidate[1] < current[1])
+}
+
 // Every notification for one batch and revision carries the same endpoint and
 // differs only by which components changed, so the union of their tokens is the
 // complete set to render.
@@ -93,6 +122,13 @@ function applyFrame(frame) {
   const target = document.getElementById(frame?.target)
   if (!target || !frame.html) return
   if (!newerRevision(frame.revision, target.dataset.solidObjectsRevision)) return
+  // Concurrent same-revision responses can carry the same frame. The target's
+  // own revision only advances once Turbo applies the stream, so what has
+  // already been applied is tracked here as well.
+  const applied = appliedRevisions.get(frame.target)
+  if (applied && !newerRevision(frame.revision, applied)) return
+
+  appliedRevisions.set(frame.target, frame.revision)
 
   const parsed = new DOMParser().parseFromString(frame.html, "text/html")
   const replacement = parsed.getElementById(frame.target)

docs/realtime.md

@@ -173,8 +173,11 @@ they are while giving the client a documented contract with per-frame revisions.
 ### What the protocol guarantees
 
 Only components whose dependencies changed are requested; the rest are never
-named in the batch. Duplicate notifications for the same batch and revision merge
-into one request, and a superseded request for the same batch is aborted. Each
+named in the batch. Notifications for the same batch and revision that arrive in
+one task merge into a single request. Notifications that arrive in separate
+WebSocket messages issue their own requests and all of their frames are applied,
+because cancelling a same-revision request would drop the components it carried.
+Only a strictly newer revision supersedes an in-flight request. Each
 frame carries its own revision and cannot overwrite a target that already holds a
 newer one. Authorization is unchanged: every component in the batch passes the
 same `authorize_query` boundary an individual refresh uses, and the batch name is

lib/solid_objects/version.rb

@@ -1,5 +1,5 @@
 # rbs_inline: enabled
 
 module SolidObjects
-  VERSION = "0.7.2"
+  VERSION = "0.7.3"
 end