feat(run-ops): read presenters — de-join control-plane relations + read-through hydration

.server-changes/route-run-presenter-reads-through-run-store.md

@@ -0,0 +1,6 @@
+---
+area: webapp
+type: improvement
+---
+
+Route dashboard and API run/batch/waitpoint presenter reads through the run store so they can be served from a separate backing store without changing call sites.

apps/webapp/app/presenters/v3/ApiBatchResultsPresenter.server.ts

@@ -1,81 +1,219 @@
 import type { BatchTaskRunExecutionResult } from "@trigger.dev/core/v3";
+import {
+  $replica,
+  type PrismaClientOrTransaction,
+  type PrismaReplicaClient,
+  prisma,
+} from "~/db.server";
 import type { TaskRunWithAttempts } from "~/models/taskRun.server";
 import { executionResultForTaskRun } from "~/models/taskRun.server";
 import type { AuthenticatedEnvironment } from "~/services/apiAuth.server";
-import { runStore } from "~/v3/runStore.server";
+import { readThroughRun } from "~/v3/runOpsMigration/readThrough.server";
+import { runStore as defaultRunStore } from "~/v3/runStore.server";
 import { BasePresenter } from "./basePresenter.server";
 
+/**
+ * Run-ops read-through wiring. All optional; absent (or `splitEnabled` falsy) collapses `call` to
+ * passthrough. `legacyReplica` is a READ REPLICA handle only — there is NO legacy-primary field.
+ */
+type ApiBatchResultsReadThroughDeps = {
+  splitEnabled?: boolean;
+  newClient?: PrismaReplicaClient;
+  legacyReplica?: PrismaReplicaClient;
+  isPastRetention?: (runId: string) => boolean;
+};
+
+// The TaskRun shape `executionResultForTaskRun` consumes. Shared by both read sites.
+const memberRunSelect = {
+  id: true,
+  friendlyId: true,
+  status: true,
+  taskIdentifier: true,
+  attempts: {
+    select: {
+      status: true,
+      output: true,
+      outputType: true,
+      error: true,
+    },
+    orderBy: {
+      createdAt: "desc",
+    },
+  },
+} as const;
+
+/**
+ * Split on: the batch row + its item rows resolve new-run-ops first, then the LEGACY RUN-OPS
+ * READ REPLICA ONLY (never the legacy primary — there is no such handle); each member run is
+ * hydrated independently via readThroughRun keyed on the member runId, so a batch whose members
+ * span migrated + abandoned runs returns the complete reachable set (the batch-spanning-the-line
+ * read; the dangling-reference termination gate is a separate, adjacent unit).
+ *
+ * Split off (single-DB / self-host): one passthrough read for the batch row + a single store
+ * id-set hydrate for the members — no legacy read, no known-migrated probe, no second connection.
+ */
 export class ApiBatchResultsPresenter extends BasePresenter {
+  constructor(
+    prismaClient: PrismaClientOrTransaction = prisma,
+    replicaClient: PrismaClientOrTransaction = $replica,
+    private readonly readThrough?: ApiBatchResultsReadThroughDeps,
+    private readonly runStore = defaultRunStore
+  ) {
+    super(prismaClient, replicaClient);
+  }
+
   public async call(
     friendlyId: string,
     env: AuthenticatedEnvironment
   ): Promise<BatchTaskRunExecutionResult | undefined> {
     return this.traceWithEnv("call", env, async (span) => {
-      // Route through the store so a NEW-resident batch resolves under the run-ops split (the
-      // router probes NEW→LEGACY and drops this client hint) instead of 404ing on a control-plane read.
-      const batchRun = await runStore.findBatchTaskRunByFriendlyId(
+      const splitEnabled = this.readThrough?.splitEnabled ?? false;
+
+      if (!splitEnabled) {
+        return this.#callPassthrough(friendlyId, env);
+      }
+
+      return this.#callSplit(friendlyId, env);
+    });
+  }
+
+  // Passthrough: batch row off the replica, members via the single run store. No legacy read.
+  async #callPassthrough(
+    friendlyId: string,
+    env: AuthenticatedEnvironment
+  ): Promise<BatchTaskRunExecutionResult | undefined> {
+    const batchRun = await this._replica.batchTaskRun.findFirst({
+      where: {
         friendlyId,
-        env.id,
-        {
-          include: {
-            items: {
-              select: {
-                taskRunId: true,
-              },
-            },
+        runtimeEnvironmentId: env.id,
+      },
+      include: {
+        items: {
+          select: {
+            taskRunId: true,
           },
         },
-        this._prisma
-      );
+      },
+    });
 
-      if (!batchRun) {
-        return undefined;
-      }
+    if (!batchRun) {
+      return undefined;
+    }
 
-      const taskRunIds = batchRun.items.map((item) => item.taskRunId);
+    const taskRunIds = batchRun.items.map((item) => item.taskRunId);
 
-      if (taskRunIds.length === 0) {
-        return {
-          id: batchRun.friendlyId,
-          items: [],
-        };
-      }
+    if (taskRunIds.length === 0) {
+      return {
+        id: batchRun.friendlyId,
+        items: [],
+      };
+    }
 
-      const taskRuns = await runStore.findRuns(
-        {
-          where: { id: { in: taskRunIds } },
-          select: {
-            id: true,
-            friendlyId: true,
-            status: true,
-            taskIdentifier: true,
-            attempts: {
-              select: {
-                status: true,
-                output: true,
-                outputType: true,
-                error: true,
-              },
-              orderBy: {
-                createdAt: "desc",
-              },
+    const taskRuns = await this.runStore.findRuns(
+      {
+        where: { id: { in: taskRunIds } },
+        select: memberRunSelect,
+      },
+      this._prisma
+    );
+
+    const runMap = new Map(taskRuns.map((run) => [run.id, run]));
+
+    return {
+      id: batchRun.friendlyId,
+      items: batchRun.items
+        .map((item) => {
+          const run = runMap.get(item.taskRunId);
+          return run ? executionResultForTaskRun(run as TaskRunWithAttempts) : undefined;
+        })
+        .filter(Boolean),
+    };
+  }
+
+  // Split: resolve the batch row new-first then off the legacy READ REPLICA only (a batch id may
+  // be cuid or ksuid, and a cuid-shaped id can still have been backfilled onto NEW, so id-shape
+  // residency is not authoritative for the row — the new-first-then-legacy probe is), then
+  // hydrate every member run independently via the per-run read-through primitive.
+  async #callSplit(
+    friendlyId: string,
+    env: AuthenticatedEnvironment
+  ): Promise<BatchTaskRunExecutionResult | undefined> {
+    // Resolve both handles ONCE so the batch row and its members never read from different DBs.
+    const newClient = (this.readThrough?.newClient ?? this._replica) as PrismaReplicaClient;
+    const legacyReplica = (this.readThrough?.legacyReplica ?? this._replica) as PrismaReplicaClient;
+
+    const readBatch = (client: PrismaClientOrTransaction) =>
+      client.batchTaskRun.findFirst({
+        where: {
+          friendlyId,
+          runtimeEnvironmentId: env.id,
+        },
+        include: {
+          items: {
+            select: {
+              taskRunId: true,
             },
           },
         },
-        this._prisma
-      );
+      });
+
+    let batchRun = await readBatch(newClient);
+
+    // Legacy READ REPLICA probe, only on a new-probe miss; skipped when past retention.
+    if (!batchRun && !this.readThrough?.isPastRetention?.(friendlyId)) {
+      batchRun = await readBatch(legacyReplica);
+    }
 
-      const runMap = new Map(taskRuns.map((run) => [run.id, run]));
+    if (!batchRun) {
+      return undefined;
+    }
 
+    if (batchRun.items.length === 0) {
       return {
         id: batchRun.friendlyId,
-        items: batchRun.items
-          .map((item) => {
-            const run = runMap.get(item.taskRunId);
-            return run ? executionResultForTaskRun(run as TaskRunWithAttempts) : undefined;
-          })
-          .filter(Boolean),
+        items: [],
       };
-    });
+    }
+
+    const readMemberRun = (client: PrismaClientOrTransaction, taskRunId: string) =>
+      client.taskRun.findFirst({
+        where: { id: taskRunId },
+        select: memberRunSelect,
+      }) as Promise<TaskRunWithAttempts | null>;
+
+    // Per-member fan-out: each member may live on a different DB, so a single nested include cannot
+    // cross the seam. Promise.all preserves batchRun.items order, unchanged from today.
+    const memberResults = await Promise.all(
+      batchRun.items.map(async (item) => {
+        const result = await readThroughRun<TaskRunWithAttempts>({
+          runId: item.taskRunId,
+          environmentId: env.id,
+          readNew: (client) => readMemberRun(client, item.taskRunId),
+          readLegacy: (replica) => readMemberRun(replica, item.taskRunId),
+          deps: {
+            splitEnabled: true,
+            // Pass the SAME resolved handles the batch row used, so the batch row and its members
+            // never resolve against different DBs. (Letting these fall through to readThroughRun's
+            // own module-level defaults would diverge from the batch read's `?? this._replica`.)
+            newClient,
+            legacyReplica,
+            isPastRetention: this.readThrough?.isPastRetention,
+          },
+        });
+
+        // not-found / past-retention members are omitted (matches today's drop-undefined behavior);
+        // the dangling-reference termination gate (separate unit) governs whether that's permitted.
+        if (result.source === "not-found" || result.source === "past-retention") {
+          return undefined;
+        }
+
+        return executionResultForTaskRun(result.value);
+      })
+    );
+
+    return {
+      id: batchRun.friendlyId,
+      items: memberResults.filter(Boolean),
+    };
   }
 }